Vol. IV No.2. For Private Circulation TECHNICAL MAGAZINE

Save this PDF as:

Size: px
Start display at page:

Download "Vol. IV No.2. For Private Circulation TECHNICAL MAGAZINE"


1 Vol. IV No.2 For Private Circulation TECHNICAL MAGAZINE

2 Vol. IV No.2 For Private Circulation The Ramco Cements Ltd Auras Corporate Centre I Floor, 98A, Dr. Radhakrishnan Road, Mylapore, Chennai Phone : , Editorial Committee Advisory Board Mr. A.V. Dharmakrishnan Mr. Balaji K. Moorthy Mr Srinivasan. M Mr S.V.R.K.Murthy Rao Mr Venkatesh Babu Honorary Chairperson Dr. Bhanumathi Das Editor Er Anil Kumar Pillai Members Er Anirban Banerjee Er Muthukumar Er Indrajit Mandal Er Kevin K.Charly Er Shashank Sharma Er Suraj Er Chandi Prasad Mohanty Er Venkatesh Pulavarty Er Farish Er Ravi G Er Sreenidh Er R.Ramachandran Er Karthick Ganesh Er Jagadeesan Er Pon Prabhu Contents Message from CEO Avoiding Hair Line Cracks Through Good Concreting Practices Techno week A Civil Engineering event with Panache Workability, Strength and Durability : Properties of Concrete with Ramco Super Grade and different types of aggregates Collaboration with Construction Professionals Interaction with Civil Engineering Institutions Feedback from Construction Professionals Particle Packing Method ( PPM) of Mix Design approach for sustainable Recycled aggregate Concrete Product Innovation at its best Ramco Dry Mix division MACE The Technical services division of The Ramco Cements Limited Awards bagged by RAMCO TECH MANTRA

3 Message From CEO Greetings from RAMCO Our team of Civil Engineers from Technical Services division - MACE have been interacting with construction professionals like you on a regular basis either through meetings or at site. We understand that the Construction sites are grappling with a major challenge scarcity of river sand and usage of alternate materials. Concrete, as we know, is the second most widely used material on this Planet. We need to ensure that its quality is not compromised. This is possible, if materials used to make concrete is of the right quality and good concreting practices are followed. It is in this context that we started the practice of making construction professionals aware of the right approach in selecting various ingredients to make concrete especially with the Manufactured or M- sand. Our objective is to collaborate with Construction professionals through bodies like Association of Consulting Civil Engineers or supporting conferences like Structural Engineers World Congress. We encourage various kinds of educational programs for the students pursuing Civil Engineering the one which is being conducted on a regular basis is the RAMCO CONCRETE CONTEST where the budding Civil Engineers get an opportunity to work with concrete. To ensure that construction professionals are aware of good concreting practices, we have been conducting number of programs which are sometimes conducted in collaboration with colleges and Universities We continue to scale newer heights as we ensure delivery of cement which is world class by adopting the latest practices in the cement manufacturing process. Our initiatives in the area of digitalization has enabled us to take advantage of online information to take faster decisions. Various professional bodies, Institutions and Ministries like Quality Circle Forum of India and Ministry of Mines have conferred awards to RAMCO Cements which clearly highlights the efforts that we have been taking on a regular basis. We are sure that the contents in this issue of TECHMANTRA will be of interest to you. We look forward to your valuable feedback and articles to support dissemination of information to construction professionals. A V Dharmakrishnan Chief Executive Officer TECH MANTRA 3

4 Avoiding Hair Line Cracks Through Good Concreting Practices Hair Line cracks can be avoided by following good concreting practices. For more detailed guidance, one can refer to SP- 25 Handbook on Causes and Prevention of cracks in Buildings published by BIS ( Bureau of Indian Standards) Curing concrete Curing of Concrete while its fresh and covering it with sheet of plastic or other similar material are critical to the curing process especially during summer when the temperature is high. Strips of wood or other similar material must be placed on all edges and joints in sheeting to prevent wind from lifting it and to minimize drying. Curing is maintenance of satisfactory moisture content and temperature in concrete for a period of time immediately following placing and finishing so that the desired properties may develop. It s better to cover the fresh concrete surface during hot weather to avoid faster evaporation of water. It s preferable to avoid oversized aggregates. Proper grading of aggregates will help in a homogeneous mix. Layout planning of Mixer drum, water drum, mixing place and wheel barrows for transportation of concrete is essential. Casting of concrete in hot weather condition can be avoided as much as possible. Concreting in shade help to reduce evaporation of water. Volumetric batching can lead to errors. Proper supervision is essential to ensure the homogeneity of mix. Approximations can lead to errors. If water is not measured properly and in case excess water goes into the mix, concrete will segregate and will have low compressive strength. 4 TECH MANTRA

5 Techno week A Civil Engineering event with Panache By: Ujwal Dsouza Director O & A Marian Projects Pvt. Ltd. Mega structures & Mega events are planned meticulously with no stone unturned to reap the best results. One such event to be recalled is the Techno week 2017 conducted by ACCEI, Mangalore center during September 2017; What an excellent repertoire organized to showcase 55 superb Civil Engineering talks & presentations, covering 18 Engineering colleges & 8 Polytechnic Institutions, the efforts of 22 resource persons picked exclusively from the construction industry & professional engineering colleges, tirelessly travelling across the breadth and length of the twin districts of Udupi & Dakshina Kannada Thear mission: to deliver the vision and technical knowhow of the Late Sir M. Vishweshwarayya to upcoming young budding Civil Engineers; Incidentally Techno week commences during the birthday of Sir M.V. as a token of remembrance to the great technocrat of the civil engineering fraternity. A noteworthy point to be mentioned is the mammoth contribution for the event by M/s Ramco Cements Ltd; Right from the planning stage of the event to the valedictory, RAMCO has been a part & parcel of this program; To add, they ve been doing this consistently for the past 10 years. To understand better- RAMCO has been providing the monetary back up for the event, the logistics, the tech-support and most noteworthy is their dedication behind the show; RAMCO manpower has been at the forefront of this affair. I have no words to express this feeling to RAMCO Just a sentence I remember Are there no limits to your generosity? Being one of the resource persons, I had the opportunity to meet various head of Departments, Principals, faculty members of various institutions and even the large student body. The interaction was electrifying and we were accepted with utmost honor; I felt that what we have been doing is just the beginning and we have miles to go as Robert Frost coined his phrase The woods are lovely, dark and deep. But I have promises to keep and Miles to go before I sleep. -Kudos to ACCEI, Mangalore & the RAMCO team. Keep it up.! Finally to brief up this entire story, I term this event as An ode to Excellence! TECH MANTRA 5

6 Workability, Strength and Durability Properties of Concrete with Ramco Super Grade and Different Types of Fine Aggregates Suresh GAB, Senior Manager-R&D Ramco Research and Development Centre, (RRDC) Chennai Abstract The use of Manufactured Sand (M-Sand) and Crushed Stone Sand (CSS) is steadily growing due to scarcity of natural River Sand. Now-a- days the sand available in the river bed contains high percentage of silt and clay. Generally CSS and a few source of M-Sand samples contain higher percentage of Fine, Flaky, Elongated and rough texture particles and negligible clay content when compared to the River Sand. At the same mix proportions, concrete workability with river sand will be higher when compared to that with M-Sand or CSS concretes due to the spherical shape and smooth texture of river sand particles. The purpose of this research is to achieve the same workability, strength and durability properties of concrete by using appropriate proportion of River Sand, M Sand and CSS without changing cement content and free water cement ratio. From the test results it was ascertained that the concrete workability, strength and durability properties show more or less equal values which could be possible by designing the concrete mix proportions based on the gradation, fines content and other physical properties of fine aggregate. Introduction River sand is a product of natural weathering of rocks over a period of millions of years. Natural rocks are disintegrated by weathered process. The disintegrated particles are worn out by streams or glacial agencies and finally get deposited on the banks of the rivers and are called River Sand also called Uncrushed Sand. Now-a-days River sand is becoming a scarce product and hence exploring alternatives to it becomes imminent. Crushed Stone Sand (CSS) or Crushed Rock Fines (CRF) is produced by crushing hard granite stones and Crushed Gravel Sand(CGS) is produced by crushing natural gravel. IS code stated that Manufactured Sand is manufactured from other than natural sources. Copper Slag, Iron Slag and Steel Slag materials are considered as Manufactured Aggregates. Recycled Concrete Aggregates also considered as Manufactured Aggregates. As per IS code, the utilization of Manufactured Aggregates in different concretes are given in Table 1. The limits of deleterious materials in the fine aggregate are given in Table 2 as specified in the same code. Crusher Stone Sand / Crushed Rock Fines / Crusher Dust / Quarry Dust are the fine particles obtained as a by-product during the crushing of rocks to produce coarse aggregates. Jaw crusher or Cone crusher is used for crushing large size rocks to small size rocks. This material contains more fine particles, dust, flaky, and elongated particles. It shows high water demand for required workability and this may lead to develop more shrinkage cracks in concrete. Thus Crushed Stone Sand should be used only after proper testing and designing the concrete mix accordingly. Production Technology of M-Sand / Robo Sand / Eco Sand To resolve the Crushed Stone Sand quality problems, the technology of processing to improve the particle shape and reduce the fines content has been developed. Rock crushed to the required grain size distribution is colloquially termed as manufactured sand (M-Sand). Generally M-Sand production involves crushing, screening and washing. M-Sand particles are cubical in shape and also some extent smooth texture. M-Sand is manufactured using technology like Rock-on-Metal and Rock-on-Rock process which is synonymous to that of natural process undergoing in river sand formation. M-Sand is produced by feeding hard stones of varying sizes to primary and secondary crushers (Jaw crusher and Cone crusher), for size reduction and these crushed stones are further crushed in Vertical Shaft Impact (VSI) crusher to attain the required grain size distribution and shape to that of River Sand. The VSI crusher by its unique design and action of attrition produces well shaped fine aggregate particles that are cubical angular particles. Generally the real M-Sand or Robo Sand quality is better than the River Sand. The comparisons between River Sand and M-Sand are given in Table 4. The VSI machine is shown in Fig. 1. In the production process of M-Sand it is a challenge to avoid generating of a high percentage of fines. Very fine particles will be removed by washing. However, the latest development of equipment combined dry screening with air classification to govern the grading curve very precisely, including the finest part. The River Sand, CSS and M-Sand fine aggregates colour and coarse particles properties are shown in Fig.2. The quality of M-Sand samples which were collected from different suppliers in Tamil Nadu are shown in Table 3 Literature Prof.Venkatarama Reddy et. al. (2012)(7) investigated that the mortar workability, compressive strength, modulus of rupture, modulus of elasticity, bond strength properties are superior by using M-Sand when compared to those of natural River Sand. 6 TECH MANTRA

7 Saeed Ahmad et al. (2008)(11) found that concrete compressive strength increased and workability decreased with increasing proportion of M-Sand. Balamurugan et.al.(2013)(8) ascertained that quarry dust can be utilized in concrete mixtures as a good substitute for river sand with higher strength at 50% replacement. Adams et.al.(2013)(9) found that the replacement of 50% fine aggregate by M-Sand induced higher compressive strength, split tensile strength, flexural strength and durability. Priyanka et.al. (2013)(10) determined that the compressive strength of cement mortar with 50% replacement of river sand by M-Sand reveals higher strengths as compared to 100% River sand mix. Experiments In this research physical properties such as sieve analysis, particle shape, specific gravity, water absorption, fines and silt content, bulk density etc of different types of fine aggregates were studied and the effect of using these materials on the performance of concrete are investigated. From the sieve analysis results it was observed that River Sand and M-Sand are coarse sand and Crusher Stone Sand is fine sand. The sieve analyses and other physical properties of aggregates are presented in Table 5 and Table 6 respectively. The main objective of this research is to establish the data to achieve more or less equal concrete workability, strength and durability properties by fixing appropriate fine aggregate proportion in the total aggregate. Nominal and Design mix concrete trials were carried out by using Ramco Super Grade cement (PPC) and different types of fine aggregates i.e. River sand, M-Sand and CSS. Basically the percentage of fine aggregate in the total aggregate was fixed based on the fine aggregate gradation, fines content (<75microns) and other physical properties. Concrete trials were also carried out with blending of coarser and finer fine aggregates. The River sand & CSS and M-Sand & CSS were blended 50:50 and 55:45 ratios by volume respectively and these blending gradation curves are shown in Fig.3. The test results of workability, strength and durability obtained for the nominal mix and design concretes are presented in Table 7 and Table 8 respectively. From the test results of nominal and design mix concretes it was ascertained that at the same cement content and free water cement ratio, all concretes were attained relatively equal slump, flow, compressive strength and durability properties by fixing appropriate proportion of River Sand, CSS and M-Sand in total aggregate based on the gradation, fines content and other physical properties of fine aggregate. This methodology is not only helpful to obtain relatively equal rheological, strength and durability properties of concrete with different quality of River Sand, CSS and M-Sand, it will be also useful to minimise the plastic shrinkage and plastic settlement cracks in the structures. The nominal mix concretes slump tests photographs are shown in Fig. 4. Concrete trials were also carried out at different percentages of replacing River Sand with Crushed Stone Sand considering relatively same workability, strength and durability of all concretes. Crushed Stone Sand was added for replacement of River Sand from 0% to 100% in the increment of 10% and the percentage of total fine aggregate proportion by volume gradually decreased from 45 % to 36% in the total aggregate volume. The River Sand and CSS blend concretes design mix proportions are given in Table 9. For all these mixes were also maintained constant cement content and free water cement ratio. The fine particles (150, 300 and 600 microns) content per one cubic meter concrete for different proportions of River Sand, CSS and blended River Sand & CSS fine aggregates are presented in Fig.5. From the graph it was observed that 300 to 600 microns particles content is gradually decreased, below 150 microns particles content gradually increased and 150 to 300 microns particles content slightly increased by gradually replacing River Sand with Crushed Stone Sand. Due to this phenomenon all concretes have attained more or less equal slump, flow, compressive strength and durability properties. The photographs of flow tests of the concretes containing the blends of River Sand and CSS are shown in Fig.6, and Fig. 7shows the results of their workability, strength and durability. Conclusions 1. By fixing appropriate weight of fine aggregate in total aggregate weight, Nominal Mix Concretes attained more or less equal slump, flow, strength and durability properties with River Sand (44%), M-Sand (39%) and Crushed Stone Sand (36%) without changing the cement content and free water cement ratio. 2. With fixing proper volume of fine aggregate in total aggregate volume, Design Mix Concretes attained more or less equal slump, flow, strength and durability properties with River Sand (45%), M-Sand (40%) and Crushed Stone Sand (36%) without changing cement content and free water cement ratio. 3. As a result of blending suitable ratios of different type of fine aggregates River sand & CSS (50:50) and M-Sand & CSS (55:45) concretes also achieved good rheological, strength and durability properties. 4. With the higher percentage of CSS (43%) in the total aggregate (Table 8), the water demand is increased for getting required workability and it decreased the strength and durability. 5. By gradually increasing of CSS and proportionally decreasing the River Sand in total volume of fine aggregate and gradually decreasing the volume of total Fine aggregate in the total aggregate volume, concretes achieved almost equal slump, flow, strength and durability properties. The above conclusions indicate that by fixing appropriate Fine and Coarse Aggregate Proportions based on Fine Aggregate Gradation, Fines content and coarser particles properties, one can make the concrete by using River Sand, M-Sand and Crushed Stone Sand or with the combination of these fine aggregates and get the almost same workability, strength and durability properties without changing the cement content and free water cement ratio. Acknowledgements The author gratefully acknowledges the initiative of The Ramco Cements Limited for providing the state-of-the-art research facilities at Ramco Research and Development Centre (RRDC), Chennai. The author is extremely grateful to The Ramco Cements TECH MANTRA 7

8 Limited, and Mr. M.Srinivasan President-MFG, Mr.SVRK Murthy Rao AVP-Process and other Technical and non-technical Staff of the Ramco Research and Development Centre (RRDC). References: 1. IS 383 : 2016 Coarse and Fine Aggregate for Concrete Specification 2. IS 516 Methods of tests for strength of concrete 3. IS 2386 (Part I - VIII) Methods of test for aggregate for concrete 4. IS Concrete Mix Proportioning Guidelines 5. IS Plain and Reinforced Concrete Code of Practice 6. ASTM C Prof. Venkatarama Reddy (2012) Suitability of Manufactured sand (M-Sand) as fine aggregate in Mortars and Concrete Project Review Article, Dept. of Civil Engg., Indian Institute of Science, Bangalore. 8. Balamurugan G and Perumal P (2013) Use of quarry dust to replace sand in concrete-an experimental study Int. Journal of Scientific and Research Publications, Vol. 3, Issue 12, Dec Adams A Joe, Maria A Rajesh, Brightson P, PremAnand M (2013) Experimental Investigation on the effect of M-Sand in high performance concrete American Journal of Engineering Research, Vol.02, Issue-12, pp Priyanka A. Jadhav and Dilip K. Kulkarni (2013) Effect of replacement of natural sand by manufactured sand on the properties of cement mortar Int. J. of Civil and Structural Engineering, Vol. 3, No.3, Saeed Ahmad and ShahidMahmood (2008) Effects of Crushed and Natural Sand on the properties of Fresh and Hardened Concrete 33rd Conference on our World in Concrete &Structures, Singapore, pp Table 1: As per IS 383:2016 Utilization of Manufactured Aggregates in Different Concretes Type of Aggregate Plain Concrete (%) Reinforced Concrete (%) Lean Concrete (<M15) (%) Coarse aggregate (a) Iron Slag Aggregate (b) Steel Slag Aggregate 25 Nil 100 (c) Recycled Concrete Aggregate (<M25) 100 (d) Recycled Aggregate Nil Nil 100 (e) Bottom Ash from thermal power plant Nil Nil 25 Fine Aggregate (a) Iron Slag Aggregate (b) Steel Slag Aggregate 25 Nil 100 (c) Copper Slag Aggregate (d) Recycled Concrete Aggregate (<M25) 100 Table 2: As per IS 383: 2016 Limits of Deleterious Materials in the Fine Aggregate Sl. No Deleterious Substance Uncrushed Sand (River Sand) Crushed Sand (CSS) Manufactured Sand 1 Coal and lignite, Max (%) Clay lumps, Max. % Material finer than 75 µm IS sieve, Max % Mica, Max (%) Deleterious materials Max. % 8 TECH MANTRA

9 Table 3: The quality of M-Sand samples which were collected from different suppliers in Tamil Nadu IS Sieve (mm) Cumulative Percentage Pass Sample-1 Sample-2 Sample-3 Sample-4 Sample-5 Sample <75 µm Zone Zone-I Zone-II Zone-I Zone-I Zone-II Zone-II Fineness Modulus Type of Sand Coarse Sand Fine Sand Coarse Sand Coarse Sand Medium Sand Fine Sand Particle Shape Cubical Angular Flaky & Elongated More Cubical Angular Cubical Angular Medium Cubical More Flaky & Elongated Table 4: Comparison between River Sand and M- Sand Sl.No Description River Sand M- Sand 1 Process Naturally available on river banks Manufactured in factory 2 Quality No control over quality since it is naturally occurring. 3 Shape Mostly sphere particles Consistent quality since manufactured in a controlled environment (VSI) Mostly cubical and angular particle ( rounded angular) 4 Below 75 microns < 3 % 10 % 5 Surface texture Smooth Smooth 6 Clay and Organic impurities Higher Zero 7 Over Sized materials May contains over sized materials ( like pebbles) Zero 8 Marine Products It contains shells etc Zero 9 Workability Better River sand mix (If adjust mix proportions based on fines and particle shapes) 10 Strength Good River sand or slightly higher 11 Eco friendly Harmful to environment. ECO imbalance, reduce ground water level and rivers water gets dried up. Less damage to environment as compared to river sand 12 Gradation It may vary load to load Maintain good gradation 13 Applications Recommended for RCC, Masonry and Plastering Recommended for RCC, Masonry and Plastering (M- Sand with low fines and less flaky& elongated particles and smooth texture is suitable for plastering works). 14 Adulteration 15 Availability Probability of adulteration is more (filtered sand). As a rule, supply shortage always brings adulterer products to the market. In monsoon more scarcity. Diminishing of Natural Rivers or River beds, not available for future generations Probability of adulteration is less Uninterrupted supply (since plenty of hills/ rocks available) 16 Price High Low when compared to River sand TECH MANTRA 9

10 Table 5: Coarse and Fine Aggregates Sieve Analysis IS Sieve Size (mm) Coarse Aggregate (single sized aggregate) 12.5 mm Agg. Percentage Pass IS 383 Limits 20mm Agg. IS 383 Limits IS Sieve Size (mm) River Sand Fine Aggregate Percentage Pass M-Sand CSS IS 383 Limits for Zone - II * * Crushed stone sand, the permissible limit on 150 μm IS Sieve is increased to 20 percent. Table 6: Coarse and Fine Aggregates Physical Properties Sl. No Description 12mmAgg. 20mmAgg. 1 Specific Gravity River Sand CSS M-Sand SSD True Water Absorption (%) Loose Bulk Density (kg/m 3 ) Compacted Bulk Density (kg/m 3 ) Flakiness Index (%) Elongation Index (%) Impact Value (%) Crushing Value (%) Angularity Number < 75 microns (%) (by wet sieve analysis) Fine Aggregate Zone - - I II I 13 Type of sand - - Coarse Fine Coarse Table 7: Nominal Mix Concrete proportions and its workability, Strength and Durability Properties with different type of Fine Aggregates Description Fine Aggregate % by weight in total aggregate River Sand (44) (MIX-NR) M-Sand (39) (Mix-NM) Crushed Stone Sand (36) (Mix-NC) Mix Proportions in Dry condition (kgs) Ramco Super Grade (PPC) Fine Agg mm Agg Total water (including water absorption) Free W/C Initial Slump (mm) Compressive Strength, MPa 1 -Day Days Days Days RCPT (Coulombs) 28 - Days TECH MANTRA

11 Table 8: Design Mix Concrete proportions and its Workability, Strength and Durability Properties with different type of Fine Aggregates Fine Aggregate % by Volume in total aggregate Description River Sand (45) M-Sand RS+CSS M-Sand + CSS CSS (36) (40) (50+50) (50+50) CSS (43) Ramco Super Grade (PPC) Fine Agg mm Agg mm Agg Water (0.55) (Free W/C) (0.585) Initial Slump (mm) Initial Flow Diameter (mm) Mix Proportions per1m 3 concrete in SSD (kgs) Compressive Strength, MPa 1 -Day Days Days Days RCPT (Coulombs) 28 Days Table 9 River Sand and CSS Blend Concretes Mix Proportions M-RC1 M-RC2 M-RC3 M-RC4 M-RC5 M-RC6 M-RC7 M-RC8 Description (45)* 100 RS (44) RS+CSS M-RC9 M-RC10 M-RC11 Fine Aggregates proportions in percentage (by Volume) (43) RS+CSS (42) RS+CSS (41) RS+CSS (40) RS+CRS (39) RS+CSS (38) RS+CRS (37) RS+CSS (36.5) RS+CSS (36) 100 CSS Mix Proportions per 1m 3 concrete in SSD(kgs) Ramco PPC River Sand CSS (CRF) mm mm Water *The percentage of Total Fine Aggregate proportion by volume in total aggregate volume Fig.1 Vertical Shaft Impactor (VSI) for producing M-Sand TECH MANTRA 11

12 River Sand (Mostly Spear particles) Crushed Stone Sand (Mostly flaky and elongated particles) M-Sand (Mostly rounded angular) Fig. 2 Fine Aggregates coarsar partciles properties (after <0.60 mm particles) Fig.3 River Sand, CSS and M-Sand gradation curves and also combined gradation curves Fig. 4 : Photographs of Slump and Flow tests for Nominal Mix Concretes with River Sand, CSS and M-Sand Fig. 6 : Photographs of River Sand and CSS(CRF) blend concrete Flow Tests 12 TECH MANTRA

13 Fig. 5 : Fine particles content (150, 300 and 600 μm) per one cubic meter concrete for different River sand and CSS proportions Fig. 7 River Sand and CSS blend concrete workability, strength and durability test TECH MANTRA 13

14 Collaboration with Construction Professionals The theme of the Event was Architecture-Structure Interaction for Sustainable Built Environment with Special focus on Why Concrete. The event was inaugurated at Bangalore by the H.H Jagadguru Sri Sri Sri Dr. NIrmalanandanatha Mahaswamiji Pontiff Sri Adichunchanagiri Mahasamsthana Math. Vice-chancelor VTU Belgaum participated as guest of honor. Our MACE division gave a presentation to the Construction Professionals. The Inauguration also witnessed Technical lecture by key speaker-mr. William J Baker Noted Structural Engineer from U.S.A. The event was attended by around 500 consulting engineers Including project teams from L&T, RMC, Adarsh Builders, Shriram group, Brigade enterprises, JMC projects, BG Shirke etc The event was preceded by a Workshop on Earthquake resistant Structures by Dr.S.K Ghosh, USA with Mr. S.C Meherotra, Mr. Vidyashankar Hoskere, and Dr.Channakeshava. The workshop was attended by P.G students apart from consulting engineers PLANT VISITS The wide array of professionals from these firms representing Precast Projects, Government Projects, Hollow blocks, Ready Mix Concrete units, Infrastructure projects and Testing laboratories visited our Ariyalur Plant for a discussion on various construction practices prevelant in their sites. They were impressed with the manufacturing facilities in our Ariyalur Plant. 1. Brigade BCV developers-precast projects 2. Hombale constructions - Govt projects /BWSSB 3. Apco concrete blocks -Hollow blocks 4. Prism RMC -RMC 5. B.G shirke construction -Govt projects /Infrastructure 6. Bureaus Veritas 7. National RMC 14 TECH MANTRA

15 ENGINEERS WORKSHOP AT VIT VELLORE A workshop for Civil Engineers was organized by RAMCO in collaboration with VIT Vellore. The topics were selected in such a way that helped the Construction Professionals understand the prevailing construction practices and also reflect upon various methods to improve them. INTERACTION WITH ASSOCIATION OF CONSULTING CIVIL ENGINEERS ( INDIA) [ ACCE(I) ] - MYSORE Er. M. S. Vijayashankar & Prof. S. Ramaswamy felicitated at Mysore ACCE (I), Mysore Centre with RAMCO organized a gettogether for Engineers of Mysore wherein two Eminent engineers Sri. M. S. Vijayashankar, and Prof. Ramaswamy were felicitated for their outstanding contribution to the Civil Engineering fraternity. Prof. H. N. Ramesh, Vice-Chancellor Bangalore University, Bangalore was the Chief Guest. Sri. K. Jayakumar, Vice President, Marketing, The Ramco Cements Ltd., was the Guest of Honour. Er. S. Ratnavel, President, ACCE (India) presided the function. Mr. Anil. K. Pillai gave a presentation on Ramco products. Approximately Two hundred professionals attended the program. INTERACTION WITH ASSOCIATION OF CONSULTING CIVIL ENGINEERS ( INDIA) [ ACCE(I) ] BANGALORE ACCE( I) Bangalore Centre together with RAMCO organized a full day event at Bangalore for the construction professionals. The chief guest for the event was Mr. Santosh hedge former lokayukta of Karnataka. Guest of Honor during the event was Mr. Puneet Vats ADG-CPWD. The event was attended by close to 650 construction professionals. Major NT project teams from L&T, Hombale, Prism RMC, Brigade, NCC and govt. bodies like BWSSB, KRIDL attended.. The programme was divided into two segments, First half i.e. Morning session was dedicated to Paper presentation by college students the participating Colleges were: Global Institute of technology, NITTE meenakshi college of engineering, PES college, BMS college of technology, AVS college, SSIT tumkur. The topics were 1) Traffic management 2) Solid waste management. 3 papers in each category were presented by 7th Semester civil engg students. Each group was represented by HOD s & faculty along with participating students. The paper presenation was chaired & judged by Jury comprising of experts from field. There was talk by LT. Col Narayan on Job possibilities for young graduates in defence forces. Around 12 colleges & 120 students with their HOD s attended the event. Evening session was started by presentation of Construction of Pir Panjal Tunnel by Shri sharanappa yallal-p.m HCC group. The Presentation highlighted the various challenges in construction & execution of project in very sensitive areas of Kashmir. The presentation was well received with Audience applauding the work & understanding the difficulties faced. The evening session also witnessed felicitation of eminent engineers: Dr. R.V Ranganath - Former HOD & Principal BMS college of technology Mr.B.S Aswathnarayan - Consulting engineer MAFE group Mr. Azeezullah khan - Former chairman MES BAI India. Military engineering services Mr. Shreekant channel - Structural enginner-propretior Precise consulting A stall was put up by RAMCO. TECH MANTRA 15

16 Interaction With Civil Engineering Institutions The Ramco Cements believes in creating awareness on Cement & Concrete Technology to the budding Civil Engineers who are pursuing their Engineering degrees. IIT MADRAS The Ramco Cements participated in the 71st RILEM Annual week International Conference on Advances in Construction Materials and Systems Adhiparasakthi college Technical symposium Ramco Concrete Centre, Vizag CONCRETE LABORATORY IN VIZAG CITY The Ramco Cements have set up a Concrete laboratory in Vizag City for the benefit of construction professionals. Dr Bhanumati Das, INSWAREB Vizag & Shri S.L.N.Sastry Chairman, Indian Institute of Architects inaugurated the Concrete Centre in the presence of President ( Marketing ), Mr Ramakrishnan. Construction professionals from the city participated and spoke during the occasion. BMS College of Technology, Karnataka BMS College of technology conducted NIRMAAN ICES 2017,a technical seminar conducted by civil engineering department of the college. The event was attended by about 350 students from Civil Engineering College across Karnataka. The chief guests of the Inaugural event were Dr. A Ravindra, IAS (Retd.) CHAIRMAN, SMART CITIES INDIA FOUNDATION & Shri. G N V Prasad Deputy Director ISRO Satellite center. The event was presided by Dr.P Dayananda Pai- Chairman, Board of governors, BMSCE & Trustee, BMSET M.D of century developers. The inaugural session also had Technical presentation by The Ramco cements limited on Challenges in concrete & Maintaining quality standards. The presentation highlighted the various challenges faced during & after concreting & various defects that arises due to this. Various recommendations on maintaining quality standards in concreting & Good construction practices were discussed. The events across two day events were Concrete cube casting competition which was Named The Ramco concrete event, Quiz session, Model erection, Design of structures. Various tests and spot quiz were also carried over 2 day s event. 16 TECH MANTRA

17 Feedback From Construction Professionals Aadithyaa Developers, Virudhachalam, Tamil Nadu We have been using Ramco cements for more than 3 years and we find the results are always satisfactory. We are glad to say that Ramco cements especially the technical team of Tiruvannamalai plays an important role in our journey. Mr.Velaiyappan from Ramco technical team helped us with his timely support and technical interventions whenever required at Site. We also thank Mr.Marimuthu AGM & Mr.Ponprabhu for their continuous encouragement and frequent visits which made us feel comfortable in doing business with Ramco and gave us an opportunity to share our ideas and feedbacks. We are looking forward to take this relationship over years to serve our valuable customers. Er.S.Chandra Bose, Consulting Civil Engineer Licensed Building Surveyor Bose Construction and Designer, Tamil Nadu Ramco Cement is a trustworthy brand in India and I have used more than bags in my sites since last year. The reason for using Ramco brand is due to its quality and customer service support. Ramco is giving excellent after sales support during construction by casting cube specimens at site and providing the test reports on 7 days and 28 days. Customer service is good and Technical officers are having very good knowledge on their product. I am really satisfied with the product and service. We can use Ramco cement without any fear. Genuine and Trustworthy product! Value for money! Er.K.Thirumalai, IQ Building Solutions, Thiruvannamalai, Tamil Nadu Ramco cement is very much suitable for all types of construction works. Excellent technical support provided by Mr.Vellaippan. Feeling very happy to be associated with Ramco cements. Er.N.Nandhakumar, A.N.Builders and Contractors, Pondicherry, Tamil Nadu We thank Ramco Cements for timely delivery and technical support through your Mace Division! Er.P.Sakthivel, President, Virudhachalam Civil Engineers Association, Tamil Nadu We thank Ramco Cements for the quality of service provided by your company. We sincerely appreciate your efficient, gracious customer service, the accountability that you have demonstrated on each project and the way you conduct business as a whole. We have and will continue to recommend your service to friends and other contacts. We look forward to continuing our relationship with Ramco. Mr R.Harikrishnan, Managing Director,Direct Engineering and Construction Excellent performance, Very good technical support and timely delivery! Aakkash Builders, Engineers & Contractors, Chennai We have been in the field of construction for the past 30 years and completed more than 500 individual houses in and around Chennai. And for the past 3 to 4 years we were in constant contact with RAMCO for various products like Cement, Super bond, Tiles fix and so on. We are very happy to say that the association with the RAMCO and with the Executive Mr.Narayanamoorthy is good. Company is also offering services like testing of the strength of the concrete at regular intervals. Almost 75 percentage of our sites are using RAMCO cement mainly for the roof and plastering. We are also using the RAMCO TILES FIX and RAMCO SUPER BOND for our sites. RAMCO app platform which is developed by the company also very much useful to know the quantity of the cement used per month. This app is also preloaded with lot of information and knowledge. I sincerely wish the RAMCO family all the very best and appreciate all the efforts of your field level team. I also wish Mr. Narayanamoorthy all future success. Mr.K.M.Sajimon, Managing Director & Sijo C Joseph, General Manager Bureaus Veritas, Bangalore, Karnataka On behalf of Bureau- Veritas ( Civil-Aid) team, I express my sincere thanks for giving us an opportunity to Visit Ariyalur cement plant. It was a nice visit for us in terms of understanding the process and latest technology adopted in a modern cement Plant. Dinesh HT,Bureau Veritas (India) Pvt. Ltd., Bangalore TECH MANTRA 17

18 Particle Packing Method (Ppm) Of Mix Design Approach For Sustainable Recycled Aggregate Concrete Subhasis Pradhan1, Shailendra Kumar2, Sudhirkumar V Barai3 1, 3 Department of Civil Engineering, Indian Institute of Technology Kharagpur, Kharagpur , India 2 Department of Civil Engineering, Guru GhasidasVishwavidyalaya (A Central University), Bilaspur , India The reuse of old concrete as a source of aggregate is a reliable alternative to Natural Aggregate (NA) in concrete construction. Because of poor quality of Recycled Aggregate (RA) the performance of Recycled Aggregate Concrete (RAC) is not up to the mark in fresh stage and hardened stage as compared to Natural Aggregate Concrete (NAC). In this work Recycled Coarse Aggregate (RCA) replaces 100% NA to produce RAC. The Particle Packing Method (PPM) is proposed for the mix proportioning of concrete. In PPM the smaller particles are selected to fill up the voids between large particles and so on. PPM is found out to be cost effective than IS code method of mix design because of requirement of lesser quantity of cement. The 7 days and 28 days compressive strength of conventional concrete and RAC using PPM design mix are very similar. But, the increment in compressive strength from 28 days to 90 days curing is higher for NAC than RAC. Keywords Recycled Coarse Aggregate (RCA), Recycled Aggregate Concrete (RAC), Natural Aggregate Concrete (NAC), Particle Packing Method (PPM), Compressive Strength Introduction The rapid growth in population and economy in India leads to the unavoidable process of industrialization and urbanization. It requires huge amount of construction works and also produces large quantities of construction and demolition (C&D) wastes. According to Ministry of Environment, Forest and Climate Change (MoEF&CC), India generates nearly 530 million tonnes of C&D waste annually. In this C&D debris waste concrete percentage is very high. The reuse of old concrete as a source of aggregate is a reliable alternative to Natural Aggregate (NA) mined from nature in concrete construction. Demolished building, rejected precast concrete member, concrete road beds, unused concrete in ready mix concrete plant and tested specimens from different laboratories are the sources of waste concrete. Recycled aggregate (RA) is yielded by crushing the waste concrete procured from C&D debris. NA and adhered hardened mortar are the constituents of RA. The concrete in which NA is replaced partially or fully by RA is known as recycled aggregate concrete (RAC). The adhered mortar layer and its quantity are the main reasons for having inferior physical and mechanical properties of RA as compared to NA and also for the poor performance of RAC. Fresh RAC has the lower workability than conventional concrete as the water absorption capacity of RA is on the higher side due to its structure [1-8]. Compressive strength of RAC is primarily influenced by replacement ratio of natural aggregate and w/c. The reduction in compressive strength of RAC is not very significant when the replacement of RCA is up to 30% [9-11]. It has been observed by many researchers that the reduction in compressive strength of RAC is up to 30% at 100% replacement of NA [5,10,11]. The techniques adopted by different researchers to improve the performance of RAC are incorporation of mineral admixture, using different mix design methods, modifying the mixing process. The addition of mineral admixtures to RAC improves the workability in fresh stage [12].The use of fly ash or GGBS as partial replacement of cement reduces the compressive strength of RAC [12,13]. However, using fly ash as the addition of cement increases the compressive strength [13]. Direct Weight Replacement (DWR) Method, Equivalent Mortar Replacement (EMR) Method [14] and Direct Volume Replacement (DVR) Method are three different aggregate replacement methods employed by different researchers. In DWR method, the weight of coarse aggregate (natural coarse aggregate (NCA) plus recycled coarse aggregate (RCA), cement and water content are kept constant for any replacement ratio. In order to produce same volumetric yields the fine aggregate amount is reduced. In Ref. [14] the EMR method was proposed and in this method RCA was considered as a two phase material rather than a single coarse aggregate. In EMR method the total volume of mortar (residual and fresh mortar) content in RAC remains same as the fresh mortar content of target natural aggregate concrete. The direct volume replacement (DVR) method considers RCA as a single phase coarse aggregate. In this method the volume of replacing RCA is same as the volume of natural aggregate. The amount of fine aggregate, cement and water are unaffected as the total volume of coarse aggregate remains constant. In EMR method workability reduces significantly and replacement ratio more than 20% needs changes in mix proportions and high dose of water reducing admixture. The compressive strength is not influenced significantly by any of these mix design methods at any replacement ratio [15]. There are some modified mixing approaches, such as Double Mixing Method, Two Stage Mixing Approach (TSMA) and Triple 18 TECH MANTRA

19 Mixing Method (TM) those have been employed by different authors to enhance the performance of RAC. Tam et al. [11] have proposed a TSMA and basically this method divides the mixing process in two parts and water is added in two steps at different times. The TSMA helps in developing a stronger ITZ by effectively filling the voids and cracks present in RCA. The compressive strength of RAC is increased up to 21% and TSMA is also effective in enhancing durability [11].The TM contributes significantly in improving workability, compressive strength and flexural strength in comparison to double mixing method. Research Importance Review of literature shows that the poor performance of RAC both in fresh stage and hardened stage is related to the inferior quality of RA. The DWR and DVR methods are not very useful in improving the performance of RAC, whereas the performance of RAC using EMR method of mix design is quite encouraging. But, the major drawback of EMR method is that 100% replacement of RCA is never achievable. There is no specific code or guidelines available for mix design of RAC as per BIS. So, most of the researchers follow the mix design procedure used for conventional concrete to produce RAC. Therefore, in the present study an attempt is made to use Particle Packing Method (PPM) of design mix [16] to improve the performance of RAC and to overcome the disadvantages of different mix design methods. Proposed Mix Design Method The basic concept of Particle Packing Method (PPM) of mix design is to minimize the voids content [17-19]. This is a process of optimization where the smaller particles are selected to fill up the voids between large particles and so on. In PPM the aim is to obtain maximum possible packing density using coarse and fine aggregates. In this regard it involves the proper determination of proportions of different size of coarse aggregates and fine aggregate and packing density of the mixture of coarse and fine aggregate. The increase in packing density leads to the minimization of voids and hence the requirement of binder and water will be less. Materials The concrete mixtures were prepared using Ordinary Portland Cement (OPC) of 53 Grade (provided by Ramco Cements Ltd.) conforming to IS: , NCA, RCA, clean river sand conforming to grading Zone II (IS: ) and potable water. The specific gravity and 28 days compressive strength of the cement used was found out to be 3.13 and MPa, respectively. The NCA used to produce conventional concrete was collected from locally available quarries with maximum size of 20 mm and satisfying the grading requirements of BIS (IS: ). The processed RCA was collected from the IL&FS Environmental Infrastructure and Services Ltd. Plant (New Delhi). The physical and mechanical properties of NCA, RCA and fine aggregate are shown in Table 1 and Table 2 by following the procedures given in BIS (IS: 2386 (Part I)-1963, IS: 2386 (Part III)-1963 and IS: 2386 (Part IV)-1963). Aggregate Fractions and Packing Density In this study mm, mm, mm and mm sized RCA and mm, mm and mm sized NCA were used along with Zone II fine aggregate to optimize the packing density. Compacted bulk density and specific gravity for each size of aggregates were determined. First mm and mm aggregates were mixed in different proportions by mass, such as 90:10, 80:20, 70:30 etc., and the bulk density of each mixture was determined. The Packing Density (PD) and Voids Content (VC) of the aggregate mixture were determined at each proportion using Eq. (1) and (2), respectively. As the smaller sized aggregate fraction increases, the bulk density of the mixture increases. But, after a certain proportion of the mixture the bulk density starts decreasing. The proportion at which maximum PD obtained was determined. This particular weight fraction of first two different sized aggregate mixtures was used while preparing mixture along with mm aggregate size. So, the mixture of mm, mm sized aggregates was blended with mm sized RCA to prepare mixtures of different proportions. The PD of the mixture of three different sized RCA was calculated for each weight fraction. The maximum PD of the mixture and its corresponding weight fraction were determined. Table 1: Physical properties of NCA, RCA and fine aggregate Coarse Aggregate Types and Sizes Properties of Aggregates 20 mm 12.5 mm 10 mm 6.3 mm Sand NCA RCA NCA RCA NCA RCA NCA RCA Specific Gravity Water Absorption (%) Bulk Density Loose (kg/m 3 ) Compacted TECH MANTRA 19

20 Table 2: Mechanical properties of NCA and RCA Properties of Aggregate NCA RCA BIS Limits (Upper) Los Angeles Abrasion Value (%) Impact Value (%) Crushing Value (%) Figure 1: Packing density of (NCA (20 mm+12.5 mm+10 mm):sand) Figure 2: Packing density of (RCA (20 mm+12.5 mm+10 mm+6.3 mm):sand) Then mm RCA was added to the mixture of mm, mm and mm sized aggregates in different proportions and the proportion at which maximum PD obtained was determined. Finally fine aggregate was added to the mixture of four different sized RCA in different proportions by mass. For each weight fraction PD was calculated and the maximum PD and its corresponding weight fraction were determined. By conducting the whole exercise maximum packing density for the RCA and fine aggregate mixture was found out to be The corresponding proportion of mm, mm, mm, mm sized RCA and fine aggregate to achieve maximum packing density was 31.9:13.7:11.4:3:4. For conventional concrete production , , size of natural coarse aggregate and fine aggregate has been used. The maximum packing density was found out to be in the aggregate proportion of 38.4:9.6:12:4 for , , sized NCA and fine aggregate. In Figure 1 and Figure 2 the packing density at different weight fractions, for the mixture of NCA with sand and RCA with sand are shown respectively. Determination of Paste Content In PPM the higher degree of packing density leads to minimum voids, maximum density and minimum requirement of binder. The total packing density (PD) obtained by mixing mm, mm, mm, mm RCA and natural fine aggregate is Hence, "Voids Content " ("VC" )"=1 PD" The total paste content in this method is the sum of the voids content found in the aggregate mixture and excess quantity of paste required to coat the aggregate particle and to obtain desirable workability of the concrete. From multiple trials, it was found out that 16% excess paste content is required for M30 grade of concrete and desired workable condition. Hence, Now, "Volume of aggregates =1-Total Voids Content" Figure 3: Schematic diagram of Two Stage Mixing Approach 20 TECH MANTRA

21 Table 3: Mix proportions for different types of concrete Coarse Aggregate (kg/m 3 ) Type of Mix Design Water (kg/ Cement Sand w/c Concrete Method m 3 ) (kg/m 3 ) (kg/m 3 ) 20 mm mm mm mm NAC IS : NAC PPM RAC IS : RAC PPM The water-cement ratio for M30 grade of concrete is determined by conducting the trials at w/c ratio 0.4, 0.43, 0.45 and 0.47 and finally it is fixed at 0.45 to achieve the target mean strength specified for M30. Mixing Process The Two Stage Mixing Approach (TSMA) proposed by Tam et al. [13] is adopted for the current study, as the process helps in improving the performance of the concrete by improving its quality at microstructure level. This may be attributed to the effect of internal curing. In this method, water is added in two stages of mixing. The steps involved in TSMA are shown in Figure 3. Performance Evaluation of Concrete In order to verify the performance of hardened concrete, both NAC and RAC (100% replacement) were prepared using PPM design mix, TSMA and established method as per IS: , normal mixing method. So, four types of concrete were produced using w/c of Fresh Concrete The property of fresh concrete was examined by its workability in terms of slump value. In this study mm slump was kept constant for both conventional concrete and RAC. In conventional concrete desired workability was obtained without addition of any admixture. But for RAC, Master Glenium ACE 30 (BASF) admixture was added 0.32% by weight of cement to achieve the required slump. Hardened Concrete The hardened concrete performance can be studied as its short term and long term behaviour. The short term properties of hardened concrete include compressive strength, tensile strength and modulus of elasticity. The compressive strength of concrete was measured using standard cubes and cylinders in accordance with BIS (IS: ). Compressive Strength The 7 days compressive strength shows negligible difference for NAC and RAC using PPM design at different w/c. For w/c 0.4, 0.43 and 0.47, the 7 days compressive strength of RAC are % higher than that of NAC. Whereas for w/c 0.45 the 7 days compressive strength of NAC is 0.8% higher than that of RAC. In PPM mix proportioning except at w/c ratio 0.4 the 28 days compressive strength of RAC are 0.2% 11.3% higher in comparison to NAC and the 28 days compressive strength obtained at w/c ratio 0.4 for NAC is 3.9% higher than that of RAC. So, the 7 days and 28 days compressive strength of RAC are slightly on the higher side than NAC. But, interestingly the 90 days curing compressive strength of RAC at different w/c ratio are % lower than NAC. There is an increase of 27 37% observed in compressive strength at different w/c ratio of NAC from 28 days to 90 days; whereas for RAC only 11 14% increment is observed for the same time period. TECH MANTRA 21

22 Table 4: Compressive strength of different types of concrete Type of 7 Days Strength 28 Days Strength 90 Days Strength Mix Design Method w/c Ratio Concrete (MPa) (MPa) (MPa) NAC PPM NAC IS: (2009) RAC PPM RAC IS: (2009) Figure 4: Compressive strength of NAC vs w/c ratio at different ages Figure 5: Compressive strength of RAC vs w/c ratio at different ages Figure 6: Compressive strength of NAC vs curing age for different w/c ratio Figure 7: Compressive strength of RAC vs curing age for different w/c ratio Figure 8: Comparison of compressive strength vs curing time (days) of NAC and RAC 22 TECH MANTRA

23 Conclusions In this study the physical and mechanical properties of the materials used are verified. The Particle Packing Method is proposed for the mix proportioning of concrete and the compressive strength of both NAC and RAC are experimentally analysed. The bulk density and specific gravity are lower and water absorption is on higher side for RCA because of the adhering mortar layer. The mechanical properties of RCA are relatively inferior to NCA, but the values are within the permissible limits of BIS. The proposed PPM design mix requires lesser quantity of cement, but more fine aggregate in comparison to IS: (2009) method of mix proportioning without affecting the properties of fresh and hardened concrete. The lesser demand for cement in the PPM design mix indicates the cost effectiveness of the method. The RAC is having lower workability than NAC. The PPM mix proportioning has no significant effect in improving the workability of the fresh concrete for both NAC and RAC. The 28 days curing compressive strength of RAC is found out to be very close to that of NAC in PPM design mix at w/c ratio But, the gain in strength from 28 days to 90 days is less for RAC than NAC. It is very difficult to separate PPM and IS code mix proportioning on compressive strength parameter of the concrete. Further study for other performance parameters are under investigation. Acknowledgments First author gratefully acknowledges the financial support provided for the project on Sustainable and Cost Effective Housing using Recycled Aggregate Based Concrete under the mega project on Future of Cities by MHRD, Government of India. Authors gratefully acknowledge the support extended by IL&FS Environmental Infrastructure and Services Ltd. Plant (New Delhi) for providing recycled aggregate. References 1. Rahal, K., Mechanical properties of concrete with recycled coarse aggregate. Building and Environment, 42(1), pp Abdulla, N.A., Effect of Recycled Coarse Aggregate Type on Concrete. Journal of Materials in Civil Engineering, 27(10), p Behera, M., Bhattacharyya, S.K., Minocha, A.K., Deoliya, R. and Maiti, S., Recycled aggregate from C&D waste & its use in concrete A breakthrough towards sustainability in construction sector: A review. Construction and building materials, 68, pp Yang, K.-H., Chung, H.-S. and Ashour, A. F., Influence of type and replacement level of recycled aggregates on concrete properties. ACI Materials Journal, 105(3), pp Butler, L., West, J. S. and Tighe, S. L., Effect of recycled concrete coarse aggregate from multiple sources on the hardened properties of concrete with equivalent compressive strength. Construction and Building Materials, Volume 47, pp Ho, N.Y., Lee, Y.P.K., Lim, W.F., Zayed, T., Chew, K.C., Low, G.L. and Ting, S.K., Efficient utilization of recycled concrete aggregate in structural concrete. Journal of Materials in Civil Engineering, 25(3), pp Manzi, S., Mazzotti, C. and Bignozzi, M., Short and long-term behavior of structural concrete with recycled concrete aggregate. Cement and Concrete Composites, 37(1), pp McNeil, K. and Kang, T. H., Recycled Concrete Aggregates: A Review. International Journal of Concrete Structures and Materials, 7(1), pp Rao, M. C., Bhattacharyya, S. and Barai, S., Influence of field recycled coarse aggregate on properties. Materials and Structures, 44(1), pp Xiao, J., Li, J. and Zhang, C., Mechanical properties of recycled aggregate concrete under uniaxial loading. Cement and Concrete Research, 35(6), pp Tam, V. W., Gao, X. and Tam, C., Microstructural analysis of recycled aggregate concrete produced from two-stage mixing approach. Cement and Concrete Research, 35(6), pp Limbachiya, M., Meddah, M. S. and Ouchagour, Y., Use of recycled concrete aggregate in fly-ash concrete. Construction and Building Materials, 27(1), pp Kou, S. C., Poon, C. S. and Chan, D., Influence of fly ash as a cement addition on the hardened properties of recycled aggregate concrete. Materials and Structures, 41(7), pp Fathifazl, G., Abbas, A., Razaqpur, A.G., Isgor, O.B., Fournier, B. and Foo, S., New mixture proportioning method for concrete made with coarse recycled concrete aggregate. Journal of materials in civil engineering, 21(10), pp Knaack, A. M. and Kurama, Y. C., Design of Concrete Mixtures with Recycled Concrete Aggregates. ACI Materials Journal, 110(5), pp Pradhan S., Kumar S., Barai S.V., 2017.Recycled Aggregate Concrete: Particle Packing Method (PPM) of Mix Design Approach.Construction and building materials, 152, pp Glavind, M., Olsen, G. S. and Munch-Petersen, C., Packing calculation and concrete mix design. The Nordic Concrete Federation, Volume 2, pp De Larrard, F. & Sedran, T., Mixture-proportioning of high-performance concrete.cement and Concrete Research, 32(11), pp De Larrard, F., Concrete mixture proportioning: a scientific approach. CRC Press. TECH MANTRA 23

24 Product Innovation At Its Best Ramco Dry Mix Division Raghunath.N In 2003 Dry Mix Plant was set up to engage the best technology to introduce products like Ready Mix Plasters, Ramco Tile Fix, and Ramco Super Fine Putty. Based on the excellent response from leading builders / customers we commenced production of customized products to suit specific needs of customers. Today the Dry Mix business has evolved to offer 18 variants of Dry Mortar products all indigenously developed in our state of the art plant at Sriperumbudur near Chennai Ready Mix Plasters : We are today in a position to offer 6 variants in our cement sand based ready mix plasters. Apart from achieving high accuracy in proportions of cement, graded sand and additives, we have moved on to offer a unique and perhaps the only one of its kind SELF CURING PLASTER.. RAMCO SELF CURING PLASTER: The conventional practice of Manual curing of conventional plasters at construction sites is labour centric and prone to errors. We at Dry Mix Division have studied this area in great depth and come up with RAMCO SELF CURING PLASTERS.In addition to a homogenous mix of cement and graded sand, SPECIAL CURING COMPOUNDS are introduced in RAMCO SELF CURING PLASTERS which ensures 100% SELF CURING PROPERTIES.Packed in a 40 Kgs bag, this product is very application friendly and cost effective. In these times of challenges in availability of labour and shortage of water which is a fast depleting resource the RAMCO SELF CURING PLASTER comes as a blessing in disguise Ramco Tile Fix : Ramco Tile Fix also affords 5 variants based on type of Tiles and application from T2 to T6.The Ramco Cements Limited is one of the very few CEMENT MANUFACTURERS offering Tile Adhesives which gives a batch to batch consistency. RAMCO SUPER BOND : Ramco Super Bond is the latest in the line of product innovation from Dry Mix Division.It is a cement sand premixed product available in a 25 Kgs bag which will provide a perfect bonding for ceiling plaster /any plaster over concrete surfaces. It attempts to replace the existing conventional practise of HACKING which weakens the concrete and creates internal damage.ramco SUPER BOND also helps reduce dependency on labour and saves time spent on HACKING Ramco THICK BED MORTAR : Ramco Thick Bed Mortar is a cement sand premixed product which forms the perfect underlayment for your expensive Tiles. With M SAND and other alternates increasingly being used in the conventional practise, RAMCO THICK BED MORTAR offers a quality solution to prevent de-bonding of Tiles and other related quality complaints Ramco Super Fine Putty : This is a cement based putty which offers excellent bonding to substrate and resistance to moisture. It is an all season player and does not flinch under any weather condition Ramco block fix : Ramco Block Fix is a Polymer Fortified Block Adhesive suitable for all kinds of blocks.the product offers the most economical way to lay AAC BLOCKS, FLYASH BLOCKS, CONCRETE BLOCKS.A 3mm thin bed application replaces the 15 mm thick bed conventional application for fixing blocks RAMCO PLASTERING COMPOUND : This is a product which is a cement lime mix which is a replacement to ordinary cement for plastering and non-structural applications. Ramco Plastering compound is perhaps the only product of its kind with cement and lime which is specifically designed for plastering and all nonstructural applications. 24 TECH MANTRA

25 MACE The Technical Services Division Of The Ramco Cements Limited Customer - Mr.Kumar from Mysore where demonstration using Ramco Cement was conducted by the MACE team Customer - Mr.Muthuraj from Karnataka where concrete demonstration using RAMCO cement was done Customer Mr Balu Reddy from Kolar where our MACE team rendered technical services Site of Er Veeranna Gowda from Yeshvanthapur where our MACE team rendered Technical services TECH MANTRA 25

26 Awards Bagged By Ramco Cement AWARD DETAILS SL.No Date of Award Name of the Award Class of Award (If any) Awarded by (Institute / Forum) S Certification for the plant Par Excellence Quality Circle Forum of India S Certification for Vidya Mandir Par Excellence Quality Circle Forum of India School Star Rating - Pudupalayam North Mines Outstanding contribution in 5S movement Best Presentation award (At National conclave, Mumbai) Only Mines in Tamil Nadu. Special award Special award Ministry of Mines, Govt. of India (1st National Conclave At Raipur, Represented By Indian Bureau Of Mines) Quality Circle Forum of India, Mumbai National Conclave Quality Circle Forum of India, Mumbai National Conclave S Certification for plant Union of Japenese Scientist & Engineers (JUSE) Best Private Sector Organization Quality Circle Forum of India Best Occupational Health Services and Certificate for Best Maintained Medical Centre (Occupational Health Centre) at the Site of Work National Award for Excellence in Energy Management Award Best OHS Excellence IAOH (Indian Association of Occupational Health) Tamil Nadu Branch Confederation of Indian Industry (CII) 26 TECH MANTRA

27 MINES ENVIRONMENT & MINERAL CONSERVATION WEEK AWARDS YEAR GROUP Category of Prize 10 Class of Award (If any) 11 Reclamation, Rehabilitation & Restoration 2nd Kattupiringium Limestone Mine Non - 12 Conventional Sustainable development 2nd Pudupalyam North Limestone Mine 13 Publicity and propoganda 2nd Reddipalayam Limestone Mine 14 Waste Dump Management 1st Periyanagalur Limestone Mine 15 Systematic and scientific development 1st Periyanagalur Limestone Mine Conventional 16 Sustainable development 2nd Periyanagalur Limestone Mine 17 Over All Performance 2nd Periyanagalur Limestone Mine MINE Waste Dump Management 2nd Reddipalayam Limestone Mine TAMILNADU MINES SAFETY ASSOCIATION YEAR GROUP Category of Prize Class of Award (If any) MINE 18 Face Working Condition & Face machinary 1st Pudupalyam North Limestone Mine 19 Transport and Workshop Facilities 1st Reddipalayam Limestone Mine 20 Ore Handling Plants & Workshop Facilities 2nd Pudupalyam North Limestone Mine 21 Personnel Protective Equipments 2nd Periyanagalur Limestone Mine 22 Welfare Amenities & Medical Facilities 1st Periyanagalur Limestone Mine 23 Conventional Injury rate performance 2nd Reddipalayam Limestone Mine 24 Electrical Installations 1st Pudupalyam North Limestone Mine 25 Standard of Supervision 1st Pudupalyam North Limestone Mine 26 Blasting Storage & Use of Explosives 2nd Kattupiringium Limestone Mine 27 Over All Performance 1st Pudupalyam North Limestone Mine 28 Team Lotus Quality Circle Gold CCQC, Kanyakumari Ramco Cement has been awarded the prestigious Chennai Best Employer Brand Award 2017 by Employee Branding Institute India for being exemplary in HR practices and having used marketing commuications effectively MAJOR AWARDS 1. Four Leaves Award instituted by Centre for Science & Environment, Government of India. 2. Winner of CII Environmental Best Practices Award 3. Winner of the Cleaner Production Measures Award 4. Green Award by Tamil Nadu Pollution Control Board, Government of TN 5. National Energy Conservation Award from Bureau of Energy Efficiency, Ministry of Power 6. Best Energy Efficient Unit from National Council for Cement and Building Materials 7. Corporate Performance Award Economic Times 8. Good Industrial Relations Award Tamil Nadu & AP Government 9. Mines Safety Award, Government of AP TECH MANTRA 27