Automated Micro-Planning and Real-time Tracking of Precast Building Components

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1 Automated Micro-Planning and Real-time Tracking of Precast Building Components A B S T R A C T Ms Rohini Prabhugaonker, ME-II, Construction & Management, D.Y Patil College of Engineering, Akurdi Prof. Mrs. Smita V. Pataskar Head of Department, Construction & Management, D.Y Patil College of Engineering, Akurdi The construction industry in India is worth around USD 500million.Precast amounts for 2% share vis-à-vis the traditional method of construction i.e. Cast in Situ.Precast concrete elements form the building blocks of various building projects which can reduce the construction time if proper sequencing is maintained. Updated information of current status is important to confirm that parts have been received in correct order and can proceed on schedule. An efficient schedule and control plan can significantly reduce construction conflicts and project delay. This study focuses on developing a planning, scheduling and real-time tracking system for precast building construction. The system facilitates to assist engineers in controlling and monitoring the entire business process of a precast plant in a real time basis. The system considers use of precast concrete elements like Hollow core slabs, prestressed beams, columns, wall panels etc.as building components. They are first identified on simple database tools like excel and then worked through the entire lifecycle from production, dispatch, to erection using customized software instead of conventional planning softwares like MSP. It can be consequently proved that overall planning process of precast projects by customized software can benefit in terms of duration of planning, number of resources required for planning, re-planning methodology, monitoring and controlling, effective decision making, reporting and root cause analysis. Index Terms: Precast, customized software, lifecycle, erection, production, tracking, delays, Root- Cause, Constants I. INTRODUCTION Precast concrete solutions for structural and ornamental elements have been extensively used all over the world both for large construction projects such as bridges as well as for modest size dwellings. Precast provides the builders with quick erection times, reduced need for plant on site, easier management of construction site, better overall construction quality and is an ideal fit for simple and complex structures. In Precast production phase, the details of components material composition during casting should be documented. Data of where they are stored are to be documented to identify and transport them with minimum time loss. In the execution phase, the components delivered to the site have to be inspected and stored, then installed. For this purpose, component has to be identified, located and tracked at the site. Finally the installations data has to be collected. The limitations in the present system of project tracking due to manual data collection and the delay in the response results in costly and complex measures to be taken to attain planned performance level. Hence real-time data is required for the control. This necessitates the introduction of automation in precast projects. II. PRECAST ELEMENT LIFE CYCLE-CONCEPT , IJAFRSE and TACE 2015 All Rights Reserved

2 The whole process of precast projects can be divided into 5 stages: Design, -Production, Storage, Transportation, and Installation. Furthermore, at least 4 roles: client, architect, Contractor, and precast factory, are involved. Nevertheless, the precast factory is always the hinge of projects. From the perspective of the precast factory, the design stage and the installation stage may be out of control. In the Design stage, the architect confirms details including shape, strength, and material(s) for all components with the client to make component information exact. Then, the precast factory produces components according to the confirmed component information. Later, the contractor installs components in the installation stage. The precast factory supplies the contractor components in the right sequence, on time. Therefore, the precast factory is always charged to plan in the domain of the production stage, the storage stage, and the transportation stage of precast projects. III. METHODOLOGY The work has been carried out in two phases, the first phase of which emphasizes on studying the basic business process of precast plant and the various tehniques that are used by precastors.this is done by working at a production facility and by referring various research papers. The phase two concentrates on analysis of the software data and how it can be useful in determining project delays and thereby enabling to perform a time and motion study. The phase-i of this study includes: 1. Problem statement formulation 2. Review of techniques of precast planning 3. Study of Precast Element life cycle at gross level 4. Erection scheduling in customized software 5. Basic framework of precast planning and tracking customized software 6. Actual data collection from precast plant concerning stage wise life cycle scheduling 7. Comparison of output with conventional planning and tracking software The phase-ii of this study includes 1. Production planning in customized software 2. Comparison of output with conventional planning and tracking tool 3. Study of precast element tracking, monitoring and controlling activity at plant 4. Determination of resource constants 5. Determination of project delays 6. Root Cause analysis 7. Time and motion studies of precast production activities IV. AUTOMATION AND CUSTOMISATION IN PRECAST INDUSTRY Precast factory is always charged to plan in the domain of the production stage, the storage stage, and the transportation stage of precast projects. Dilemmas occur when creating precast project plans. For example, high production of components produced with high operating costs may accompany shortages of resources and insufficiency of storage space. Contrarily, low productivity may idle resources and storage space. Conventional planning methods used by planners do not always give realistic results and observed to add to above problems. An investment should be made in information technology to link the , IJAFRSE and TACE 2015 All Rights Reserved

3 computer systems of the company and its suppliers so that they can coordinate the delivery of components and materials V. CASE STUDY A case study is carried out on a precast multi-level car parking project to implement the entire research methodology. The project has an area of 4, 50,000 sqft and has 12 levels. The major works are in Precast whereas some portion consists of Cast-In-Situ works 1. Project Planning tools used at the plant VI. RESULTS a) MS Project (MSP) b) Microsoft Excel c) Customized Software-The software is driven by Barcode and Android Based Cloud Technology and exclusively developed taking into account the business process of the plant. It uses MS Excel as the data input platform. The logics have also been developed using MS Excel formulae. 1. Erection Planning Table 6.1 Comparison with respect to Erection planning (Conventional vs Automated) Factors Conventional planning(msp,ms EXCEL) Customized Software Basis Past Experience As per realistic data inputs Cast-In-Situ Works Separate planning needs to be done Provision to consider Cast-In-Situ Planning construction time before precast erection commences Structural Dependencies No check for sequence of planning based on structural dependencies Machinery Utilization Resources cannot be optimized resulting in idle time of machinery Resource allocation and resource sharing between projects No provision to book resources as per project requirements, leads to clashes between various project personnel. Element can be planned for erection only if element it depends on is planned earlier Idle time of machinery utilized to schedule element requiring lesser erection time Resource booking enabled, facilitating use of resources between more than one projects as per booking period. Figure 6.1 Erection plan in customized software shows erection days generated considering Machinery erection speed (time) per element, machinery utilization also taking into account consumption of duration for Cast-In-Situ works , IJAFRSE and TACE 2015 All Rights Reserved

4 2. Production Planning Figure 6.2 a) Moulds defined as per Element Geometry along with mould specifications b) Production batches generated with standard element life cycle which also can be crashed , IJAFRSE and TACE 2015 All Rights Reserved

5 Table 6.2 Comparison with respect to Production planning (Conventional vs Automated) FACTORS Production Batch Creation Resource booking and sharing Production Batch Crashing Planned dates to every stage of element life cycle CONVENTIONAL PLANNING(MSP,MS EXCEL) At Gross level based on manual calculations. No provision can be made leading to unrealistic plans, clashing of resources If batches don t fit in required timeline, crashing cannot be done, requires manual revisions or based on excel formulae Element life cycle stage planning is time consuming CUSTOMISED SOFTWARE Based on mould parameters, element shapes & sizes automatically generated Moulds can be appropriately booked considering production priority of other projects Standard life cycle can be easily crashed to obtain revised planned production dates and batches Every minute stage of element production is mapped and planned dates for each are auto-generated leading to realistic schedule 3. Determination of Resource Constants From actual dates generated in past or ongoing projects, the quantities of steel and concrete consumed can be determined thus enabling to calculate labour constants. When gross level costing needs to be done in Tendering Stage for a new project, these constants can be utilized directly to estimate the total labour cost given the basic data of project , IJAFRSE and TACE 2015 All Rights Reserved

6 Figure 6.3 Quantities and labour estimate from actual data of production Figure 6.4 Quantities and labour estimate using above constants for a new project 4. Delay Analysis and Time & Motion Studies , IJAFRSE and TACE 2015 All Rights Reserved

7 Figure 6.5 a) Bill of materials for production batch-1 elements b) Software generated Planned and Actual dates for activity of Preparation of steel cage Figure 6.6 a) Bill of materials for production batch-2 elements b) Software generated Planned and Actual dates for activity of Preparation of steel cage Activities Production Batch Batch 1 Batch 2 Table 6.3 Delay and efficiency (Planned Steel (Actual Steel Cage Ready Date- Cage Ready Date- Delay Planned Steel Actual Steel cage cage Start Date) Start Date) 4 hours 4 hours 7 hours 3 hours 8 hours 4 hours Efficiency 57% 50% The delays for both production batches have been calculated from actual durations obtained through software considering working hours from 9.00AM to 5.00PM i.e 8 hours. The grey area in the activity Preparation of steel cage can be highlighted since the efficiency is considerably low. This activity therefore needs to be analyzed for its standard processes so as to improve upon the duration consumed. Similarly, by determining delays for other production activities, time and motion study can be performed to improve on final production duration. VII. CONCLUSION , IJAFRSE and TACE 2015 All Rights Reserved

8 Gross level planning by conventional method does not allow to take into consideration all the aspects needed to form a near-to-realistic erection plan of precast elements. However most of the shortcomings can be overcome by planning in the customised software thus facilitating element-level micro planning that will further help to make an optimised production and dispatch plan. VIII. REFERENCES [1] Nan Li and Burcin Becerik-Gerber, A.M.ASCE, Life-Cycle Approach for Implementing RFID Technology in Construction: Learning from Academic and Industry Use Cases,ASCE, Journal of Construction Engineering and Management/December 2011 [2] W. T. Chan and Hao Hu, Production Scheduling for Precast Plants using a Flow Shop Sequencing Model, ASCE,Journal of Computing in Civil Engineering/July 2012 [3] Jouni Ikonen, Antti Knutas, Harri Hämäläinen,Marko Ihonen,Jari Porras,Tommi Kallonen,,Use of Embedded RFID tags in Concrete Element Supply Chain, Journal of Information Technology in Construction - ISSN [4] Low Sui Pheng, Choong Joo Chuan, Just in time Management of precast concrete components, ASCE, Journal of Construction Engineering and Management November/December 2001 [5] (National Precast Concrete Association) [6] (Precast/Prestressed Concrete Institute) [7] [8] , IJAFRSE and TACE 2015 All Rights Reserved