Sisal Composite Ltd. Apparel 4 Ltd. JM Knit Ltd. Natun Para, Hemayetpur, Savar, Dhaka-1340 ( N, E)

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1 Revision: issue 1 Date: 11 June 2014 Sisal Composite Ltd. Apparel 4 Ltd. JM Knit Ltd. Natun Para, Hemayetpur, Savar, Dhaka-1340 ( N, E) 24 th May 2014 Structural Inspection Report Observations & Actions Authors: Robert Read, Piotr Czapko Checked by: Hugh Griffin Approved by: Aidan Madden Category Amber Category RED if actions are not immediately progressed as requested on pages 3 & 4 DEA 1

2 2 Executive summary On Saturday 24 th May 2014 Mr. Robert Read (lead) and Mr Piort Czapko of Arup carried out a visual structural survey of Sisal Composite Ltd. at the address and coordinates shown on the cover of this report. We met with Mr Shahnoor (Chief of Operations), Mr. Md. Sanoar Hossain (Assistant Manager Accounts and Finance) and Mr. Md. Masud Rana (Executive Admin & Compliance). Sisal Composite Ltd. occupy the first floor of two adjacent buildings. The first building ( Building 1 ) is a five storey RC frame which is also occupied by Apparel 4 Ltd, JM Knit Ltd. and Snap Button Industries Ltd. The upper floors are used for garment manufacture whilst the ground floor is used for manufacturing buttons. The adjacent Building 2 has four stories which have been constructed across the whole site with the four bays to the east of the site having an additional fifth storey. Building 2 is principally used for storage by Sisal Composite Ltd, Apparel 4 Ltd and JM Knit Ltd. We inspected all accessible parts of the factory buildings. Construction of the Ground to 3 rd floor of Building 1 was reportedly finished in 2007, the fourth floor was added in We were shown an industrial permit drawing for a five storey industrial building that was signed by the Union Purishad (UP) Chairman in May We were also shown a residential permit drawing for a building on the same site that was approved in July In addition we were shown undated structural layout drawings. Whilst the shape of the buildings inspected was similar to those shown on the drawings there were some discrepancies, most notably the column sizes, slab spans and the location of the rear staircase. No soils report was available for this building.

3 3 Executive summary (Continued) For Building 2 we were shown a permit drawing for a 4-6 storey commercial building which was approved by the UP Chairman in March We understand that the building was constructed in two phases. Phase 1 consisted of the rear 6 bays up to 3 rd floor, during Phase 2 the front 4 bays were built up to 4 th floor (reportedly completed in 2012). There were no structural drawing for Phase 1 although undated drawings were available for the 5 storey portion built in A soils report dated 2011 suggested piled foundations. The permit drawing shows pad foundations. There was no evidence of overloading, distress, damage, excessive deflections or settlements. We have important and urgent concerns in relation to the adequacy of the structural support columns for the both Building 1 and 2. The columns appear to be stressed to levels that require immediate review. The following immediate actions are required to be carried out to reduce the loads in the columns: 1. The water tank on the roof of Building 1 should be emptied. Alternative temporary water tanks may be located elsewhere on the roof. Suitable locations should be determined by a suitably qualified Structural Engineer. 2. Loading restrictions must be imposed in the area highlighted below for Building 2. The toilets may continue to be used but the area external to the toilets must have all loading removed and must remain unoccupied pending completion of a Detailed Engineering Assessment. 3. The high storage loads at the first floor of Building 2 should be reduced. Average floor loading on all floors should not exceed 2 kpa (Building 1 and 2).

4 Executive summary (Continued) Area where immediate actions are required for Building 1 Storage loading and all other loads must be managed to ensure that a maximum load of 2kPa is not exceeded on any floor above Ground Floor. Water tank to be drained 4

5 Executive summary (Continued) Area where immediate actions are required for Building 2 5 The toilets may continue to be used but all loading must be removed from the area shown shaded at all levels above Ground Floor Storage loading and all other loads must be managed to ensure that a maximum load of 2kPa is not exceeded at any floor above ground floor.

6 Executive summary (Continued) We would recommend that a Detail Engineering Assessment for this building be completed within 6 weeks of receiving the report. If the building owners are not in a position to complete these actions immediately, both buildings should be re-classified as Category Red and evacuated. A high level and non exhaustive list of key concerns are: ITEM 1 - High stress in columns. ITEM 2 - Localised areas of storage leading to high imposed loads being applied to the structure. ITEM 3 - Inconsistent and missing record information ITEM 4 - Cantilevering half landing ITEM 5 - Beam depths vary between floors ITEM 6 - Hairline cracking observed in beams and slab soffits We see no reason to suspend operations in the facility due to these concerns (subject to the required actions noted at the end of this report). Further actions with associated priorities and timeframes are given at the end of this report. Please note that these actions should be completed as soon as practically possible and certainly within the timeframe noted. We have reviewed the property from an outline seismic perspective and would consider that the building along with many others in the Dhaka region to have a significant risk in a major Seismic event. Our Limitations and Assumptions are also noted at the end of this report. 6

7 7 Building Extents

8 Sisal Composite Ltd. rent the first floor of 2 buildings. Building 1 is 5 stories high. The height of Building 2 varies between 4 and 5 stories. N Building 1 Building 2 8 Building Extents Site Plan

9 Building 1 East elevation Building 2 East elevation 9 Building Extents Elevations

10 Building 1 Building 2 South Elevation 10 Building Extents Elevations

11 Building 1 West Elevation 11 Building Extents Elevations

12 Construction of the ground to 3 rd floor of Building 1 was reportedly finished in 2007, the fourth floor was added in We were shown an industrial permit drawing signed by the Union Purishad Chairman in March 2013 for a five storey industrial building. We were also shown a drawing for a residential building on the site that was approved in July 2012 (see below). There was no soils report available for this building. Industrial permit (2013) Residential permit (2012) Building Extents Permit Information Building 1

13 Roof Telecommunications antenna Fourth Floor Cutting Sewing, Finishing (Apparel 4 Ltd) Third Floor Cutting Sewing, Finishing (Apparel 4 Ltd) Second Floor Cutting Sewing, Finishing (JM Knit Composite) First Floor Cutting Sewing, Finishing (Sisal Composite Limited) Ground Floor Button manufacture (Snap Button Industries Ltd.) Building Extents Floor Usage Building 1

14 A permit drawing for Building 2 was available showing a 4-6 storey commercial building, this was approved by the UP Chairman in March We understand that Building 2 was constructed in two phases. Phase 1 consisted of the rear 6 bays up to 3 rd floor, during Phase 2 the front 4 bays were built up to 4 th floor (reportedly completed in 2012). There were no structural drawings for Phase 1 although undated drawings were available for the 5 storey portion built in A soils report dated 2011 for a 6 storey residential building suggested piled foundations although pad footing details are shown on the permit and structural drawing. Original 4 storey building construction date unknown Permit drawing available Extension built in 2012 Undated structural plans available. Building Extents Permit Information Building 2

15 Roof Fourth Floor Predominantly storage (Apparel 4 Ltd) Third Floor Predominantly storage (Apparel 4 Ltd) Second Floor Predominantly storage (JM Knit Composite) First Floor Storage (Sisal Composite Limited), leather goods manufacture Ground Floor Leather goods manufacture Building Extents Floor Usage Building 2

16 16 Structural System

17 Structural Description Building 1 is a 5 storey reinforced concrete (RC) building with a two way spanning slab supported by downstand beams. There is a two storey RC structure supporting a steel telecommunication tower on the roof. Horizontal stability is assumed to be provided by frame action with additional stiffness provided by masonry façade walls. The floor slabs are assumed to act as diaphragms to transfer stability loads back to the vertical elements. N 17 Structural System Building 1

18 Building geometry Column grid varies, maximum 4.6m x 5.15m at front, 7.0m x 6.2m at the rear Column size varies typically 380mm x 250mm internally at ground floor Slab thickness typically 165mm (excl. finishes) Typical finishes thickness 45mm Record information shows piled foundations, this could not be confirmed on site Slab cantilevers beyond columns along eastern side of building Slab edge along northern edge of building not parallel with grid. Varies from no offset to 1.5m cantilever (max.) Brick aggregate 18 Typical downstand beam/ column junction detail Structural System Building 1 View of cantilevering slab on eastern side of building

19 Structural Description Building 2 is a reinforced concrete (RC) building, the height of which varies between 4 and 5 stories. The two way spanning slab is supported by downstand beams. Horizontal stability is assumed to be provided by frame action with additional stiffness provided by masonry façade walls. The floor slabs are assumed to act as diaphragms to transfer stability loads back to the vertical elements. N 19 Structural System Building 2

20 Building geometry Column grid varies, maximum 3.8m x 4.9m. Column size varies typically 300 x 300mm at ground floor. Slab thickness typically 150mm (excl. finishes). Typical finishes thickness 40mm. Slab cantilevers beyond columns along southern side of building, max. 1.3m Soils report suggests piles, pads foundation shown on drawings, not confirmed on site. Brick aggregate in original columns, stone aggregate in recent extension columns. 20 Balconies on eastern elevation Structural System Building 2 View of cantilevering slab on southern side of building

21 21 Observations

22 22 High column stresses

23 The columns highlighted have very high compressive stresses. Immediate actions are required to reduce the loads in these columns as stated later in this report This column is subject to loads from overhead water tank which is cantilevering beyond the columns High column stresses Building 1 23

24 The columns highlighted have very high compressive stresses. Immediate actions are required to reduce the loads in these columns as stated later in this report This column is subject to loads from toilet cubicles and finishes which sit on a cantilevering slab High column stresses Building 2 24

25 25 Localised areas of storage leading to high imposed loads being applied to the structure

26 In a number of locations in Building 2 there are areas of storage leading to significant imposed loads being applied to the structure. A suitably qualified Structural Engineer should confirm the capacity of the structure and produce loading plans showing the maximum allowable imposed load. First floor (used by Sisal Apparel Ltd.) Fourth floor (used by Apparel Four Ltd) 26 High imposed floor loads Building 2

27 27 Inconsistent and missing record information

28 There are inconsistencies between the as-built structural drawings and the structure that was inspected as highlighted below. The spans measured on site differ from dimensions shown on the as built structural drawings. In some areas the slab cantilevers which is not shown on the record information. The stair to the rear of the building is offset from the column grid as shown. Inconsistent and missing record information Building 1 The column sizes shown on the record information do not match the sizes measures on site. Internal columns are shown as C4 (300mm x 660mm). On site these columns were measured as 380mm x 250mm. 28

29 The two storey structure supporting the antennas on the roof and the antennae themselves are not shown on permit or structural drawings. A suitably qualified structural engineer should confirm that there is sufficient capacity in the structure supporting the unpermitted development. Detailed as-built information should be produced. 29 Inconsistent and missing record information Building 1

30 Original Extension Permit drawing There are no structural drawings for the original portion of Building 2, drawings are only available for the recent horizontal extension. The permit drawing is for a proposed commercial building Structural drawing Inconsistent and missing record information Building 2 30

31 31 Cantilevering half landing

32 The half landing of the stair at the back of Building 1 appears to cantilever in both directions from the column that is supporting it. The design of the half landing and column should be checked for patterned imposed loads under crowd loading (i.e. during evacuation in an emergency). At higher levels it is possible that the masonry wall between the stairwell and main floor plate is providing some vertical support. Ground floor View from inside stairwell. Cantilevering half landing Building 1 32

33 33 Beam depths vary between floors in Building 2

34 The depth of the edge beam varied between the 3 rd and 2 nd floor in Building 2, there is no information showing the depth the beam was designed to be. A suitably qualified Structural Engineer should confirm that the shallower beam at second floor has sufficient capacity to support the loads applied to it. Third floor Second floor Varying beam depths Building 2 34

35 35 Hairline cracking observed in beams and slab soffits

36 Cracking in beams was observed at underside of 4th floor and roof slabs. Flexural cracking was observed from the third floor (soffit of fourth floor slab Cracks to be reviewed by removing plaster to confirm that they do not extend into RC structure. If cracks are reflected in the structure, crack widths to be monitored. A suitably qualified Structural Engineer should be consulted if crack widths increase. Cracks in beams and slabs Building 1 36

37 37 Priority Actions

38 Problems Observed ITEM 1 - High stress in columns. ITEM 2 - Localised areas of storage leading to high imposed loads being applied to the structure. ITEM 3 - Inconsistent and missing record information ITEM 4 - Cantilevering half landing ITEM 5 - Beam depths vary between floors ITEM 6 - Hairline cracking observed in beams and slab soffits 38

39 Item 1 and actions High column stresses verify concrete strength in columns Priority 1 (Immediate - Now) Priority 2 (within 6-weeks) Priority 3 (within 6-months) Drain water tank on Building 1. Alternative temporary water tanks may be located on the roof. Suitable locations should be determined by a suitably qualified Structural Engineer. Remove loading from area highlighted in the attached sketch in Building 2. In Building 1 and Building 2 limit floor loading to 2kPa maximum on all floors above ground floor.support each floor down to a firm foundation in area shown overleaf, this may be achieved by propping the area concerned. Qualified Structural Engineer to review design, loads and stresses in all columns as part of a Detailed Engineering Assessment (DEA) (see scope below). Verify in-situ concrete strength by testing 100mm diameter cores taken from 4 no. columns (minimum). Qualified Structural Engineer to determine safe locations for coring. Prior to coring, the floor beams supported by the column should be propped through all levels to ground floor. The column reinforcement should be exposed to ensure that it will not be damaged during coring. Following coring, the column should be repaired using suitable repair mortar before de-propping the floor beams. Detailed Engineering Assessment to be completed. Provide calculations showing the structural adequacy of all columns. Provide results of concrete strength tests. Develop remediation measures as required by findings of DEA. Produce and actively manage a loading plan for all floor plates within the factory giving consideration to floor capacity and column capacity. Continue to implement load plan 39

40 Detail Engineering Assessment This Schedule develops a minimum level of information, Analysis and testing expected as part of a Detail Engineering Assessment. The Building(s) have been visually assessed and it is deemed necessary that a detailed engineering assessment be carried out by a competent Engineering Team employed by the factory Owner. This Request should be read in conjunction with the BUET developed Tripartite Guideline document for Assessment of Structural Integrity of Existing RMG Factory Buildings in Bangladesh (Tripartite Document), the latest version of this document should be referenced. T his document also gives guidance on required competency of Engineering Team. We expect that the following will be carried out: 1. Development of Full Engineering As-Built Drawings showing Structure, loading, elements, dimensions, levels, foundations and framing on Plan, Section and Elevation drawings. 2. The Engineering team are to carry out supporting calculations with a model based design check to assess the safety and serviceability of the building against loading as set out in BNBC-2006, Lower rate provisions can be applied in accordance with the Tripartite Guidelines following international engineering practice, justification for these lower rate provisions must be made. 3. A geotechnical Report describing ground conditions and commenting on foundation systems used/proposed. 4. A report on Engineering tests carried out to justify material strengths and reinforcement content in all key elements studied. 5. Detailed load plans shall be prepared for each level showing current and potential future loading with all key equipment items shown with associated loads. 6. The Engineering team will prepare an assessment report that covers the following: As-Built drawings including Plans at each level calling up and dimensioning all structural components Cross sectional drawings showing structural beams, slabs, floor to floor heights, roof build-ups and Basic design information of the structure Highlight any variation between As-built compared to the designed structure Results of testing for strength and materials Results of geotechnical assessment and testing/investigation Details of loading, inputs and results of computer modelling Commentary on adequacy/inadequacy of elements of the structure Schedule of any required retrofitting required for safety or performance of Structure Any proposals for Retrofitting to follow guidance developed in the Tripartite Document 40

41 Executive summary (Continued) Area where immediate actions are required for Building 1 Storage loading and all other loads must be managed to ensure that a maximum load of 2kPa is not exceeded on any floor above Ground Floor. Water tank to be drained 41

42 Executive summary (Continued) Area where immediate actions are required for Building 2 42 The toilets may continue to be used but all loading must be removed from the area shown shaded at all levels above Ground Floor Storage loading and all other loads must be managed to ensure that a maximum load of 2kPa is not exceeded at any floor above ground floor.

43 Item 2 and actions Areas of localised high storage loads Priority 1 (Immediate - Now) None required. Priority 2 (within 6-weeks) Suitably qualified Structural Engineer to confirm capacity of structure supporting storage areas in Building 1 and 2 and to produce plans showing maximum allowable floor loads. Priority 3 (within 6-months) Continue to implement load plan. 43

44 Item 3 and actions Inconsistent and missing record information Priority 1 (Immediate - Now) Priority 2 (within 6-weeks) Priority 3 (within 6-months) None required As part of DEA (see Item 1) a suitably qualified Structural Engineer is to confirm that as-built structure has sufficient capacity, particularly areas that differ from as-built structural information e.g. undocumented cantilevers, columns that are smaller than shown on drawings. Suitably qualified engineer to confirm that there is sufficient capacity in the structure supporting the unpermitted antennae support structure. Suitably qualified engineer to confirm that foundation type for Building 2. Engineer should also confirm that foundations have sufficient capacity for the applied loads. Suitably qualified structural engineer to check, collect information and produce accurate and complete as-built documentation as soon as possible. 44

45 Item 4 and actions Cantilevering half landing in rear stair of Building 1 Priority 1 (Immediate - Now) None required Priority 2 (within 6-weeks) Suitably qualified engineer to check capacity of cantilevering half landing and column at ground floor in Building 1. Particular attention should be given to patterned crown loading (e.g. during an evacuation) Priority 3 (within 6-months) None required 45

46 Item 5 and actions Varying edge beam sizes between 2 nd and 3 rd floor in Building 2 Priority 1 (Immediate - Now) None required Priority 2 (within 6-weeks) A suitably qualified engineer should confirm that the shallower beam at second floor has sufficient capacity to support the loads applied to it. Priority 3 (within 6-months) None required 46

47 Item 6 and actions Hairline cracks in beams and slabs in various locations. Priority 1 (Immediate - Now) Priority 2 (within 6-weeks) Priority 3 (within 6-months) None required. Sections of plaster finish to beams to be removed to investigate if cracks penetrate the building structure. As part of DEA for Item 1, Building Engineer to carry out design check on beams to confirm that these cracks are non-structural. Building Engineer to prepare allowable floor loading plans. None required. 47

48 Survey Limitations and Assumptions This report is for the private and confidential use of Accord for whom it was prepared together with their professional advisors as appropriate. It should not be reproduced in whole or in part or relied upon by third parties for any use without the express written permission of Arup. This report can be used in discussion with the supplier or factory owner as a means to rectify or address any observations made. The report is not comprehensive and is limited to what could be observed during a visual inspection of the building. This Report is not intended to be treated as a generalised inspection and does not cover the deterioration of structural members through dampness, fungal or insect attack, nor does it deal with problems and defects of a non-structural nature. Other non structural aspects of the building such as fire safety have not been assessed in this survey. Except as otherwise noted, drains and other services were not viewed or tested during our inspection and are therefore similarly excluded from this Report. We have not inspected any parts of the structure which are covered, unexposed or inaccessible and we are therefore unable to report that any such part of the property is free from defect. External inspection of the façade walls has generally been carried out from ground level only by visual sighting. No opening up works were carried out (except as noted) and we rely on the Architects and Engineers drawings provided to us for our views on concealed parts of the structure and in particular foundations. Strengths of materials and components are untested and we recommend that the factory owners Building Engineer carries out insitu testing over and above those suggested to satisfy themselves with the material strengths and component details. Recommendations, where given, are for the purpose of providing indicative advice only, are not exhaustive, relate solely to identifying key and obvious structural defects as identified in this presentation, and do not take the form of or constitute a specification for works. We take no responsibility for the works as constructed. This report does not interfere with the factory owners Building Engineers responsibility for the structural performance of this building, The Building Engineer remains fully responsible for the structural adequacy of the building. This report does not comment in detail on the future seismic performance of the building and only highlights the fact that the building may experience significant damage or collapse in a seismic event along with many others in the Dhaka region. The observations in this report are based on the Engineering Judgement of the lead surveyor/engineer at the time of the survey. We assume in making these observations that no covering up of faults defects, filling or plastering over cracking or significant repair work has been carried out by the building owner. Any future alteration or additional work by the building owner will void this report. 48