EQUIVALENT INITIAL STRUCTURAL SAFETY ASSESSMENT

Transcription

1 EQUIVALENT INITIAL STRUCTURAL SAFETY ASSESSMENT , Baizid Bostami Road Nasirabad I/A, Chittagong Chittagong The Alliance for Bangladesh Worker Safety Page 1/11

2 Introduction to the Report The following report contains a site profile and summary of non-conformities identified during an onsite assessment commissioned by the Alliance for Bangladesh Worker Safety (Alliance) and conducted by a third-party Qualified Assessment Firm (QAF). The assessment was conducted against the Alliance for Bangladesh Worker Safety Assessment Protocols (APs) and Fire Safety and Structural Integrity Standard, which is harmonized with the factory assessment guidelines developed by Bangladesh University of Engineering and Technology (BUET) for the Bangladesh National Tripartite Plan of Action (NTPA). The goal of the Alliance process is to provide clear and practical technical requirements by which Bangladeshi Ready Made Garment (RMG) Factories producing for Alliance members may be consistently and fairly evaluated for fire, structural, and electrical safety in a non-duplicative manner. Each assessment will prompt action plans that will be used by RMG factories to systematically and sustainably improve safety conditions for garment workers. Beyond tracking and reporting on action steps taken in a transparent manner, the Alliance organization and its members will seek to further support factory improvements through technical assistance, training, implementation support for functional Worker Committees, and in some cases financial assistance and wage support for workers if factories are closed for remediation. The contents of the report do not constitute a guarantee of compliance with the applicable laws, the Alliance Standard or the absolute or continued safety against fire, electrical and/or structural integrity issues that may lead to injury or loss of life. The report is designed to provide a non-exhaustive summary of risk issues, based on a limited sampling and duration of time onsite by the named QAF. Neither the QAF nor the Alliance can certify or guarantee the quality, outcome, or effectiveness of actions taken in response to the report. For more information and report feedback please go to: The Alliance for Bangladesh Worker Safety Page 2/11

3 GENERAL INFORMATION General Information Country: Province: City: Bangladesh Chittagong Chittagong Zip Code: 4210 Audit Duration: Re-Audit: 1 Days Re-Audit After 0 Months Draft Report Date : 10 June 2014 Final Report Date : 12 November 2014 Are all Action Items From Previous Assessment Completed?: Buildings in Complex : Number of Building Levels (Stories) : Approximate Building Area (SF) : Date of Building Construction : Date of Last Building Renovation/Addition : Is the Building mixed use?: Ancillary Structures in Complex : Number of Ancillary Levels (Stories) : Approximate Ancillary N/A There is 1 Main factory building in the complex. 6 stories with an additional steel framed roof SF 2002 N/A No There are two ancillary structures in the complex. Building 2 and Building 3 Building 2 is two stories and Building 3 is three stories Unknown. The Alliance for Bangladesh Worker Safety Page 3/11

4 Structures Area (SF) : Number of Occupants : Exterior Facade Description : Structural System Description : 2200 workers. The perimeter façade of the factory and ancillary buildings typically consists of non-bearing masonry infill walls. In general, the masonry walls are abutted tightly against the structural concrete frame members. A plaster finish covers the exterior surface of the masonry walls. The Main Building is a cast in place reinforced concrete structure. The typical structural floor system consists of two way concrete slabs (6 thick) cast integrally with concrete beams located on the column lines. The building lateral force resisting system for wind and seismic loads appears to be a beam/column moment frame system. Than ancillary buildings have similar structural systems as the main building. The Alliance for Bangladesh Worker Safety Page 4/11

5 ASSESSMENT FINDINGS Structural System Design If the structure has been previously expanded, was the structural impact on the entire structure analytically evaluated and confirmed by a qualified structural engineer. At the roof of the Main Building we observed undocumented rooftop construction and utilization. A structural steel framed roof has been added, which covers approximately 75% of the existing roof area. As described above the existing roof level would correspond to the sixth floor of the building as shown on the construction documents. Because the existing structure is over two stories smaller than that shown on the construction drawings, the global impact of the undocumented roof structure as it relates to foundation and column adequacy is not perceived to be a concern. However, concentrated loads applied by the steel structure at the sixth level roof could locally exceed the forces for which individual members were design. In this respect, it is important that the building engineer of record review and verify the adequacy of the existing building to support the specific loading conditions created by the added roof structure. Based on the documentation provided it is not known if the building engineer of record has provided this review and confirmation. Additionally, it is unknown if the roof shed structure was constructed in accordance with an engineered design. There is also an undocumented cell tower on the roof of the structure. Visual Assessment: Visual assessment of added roof structure Have a qualified structural engineer complete an analytical evaluation of the structural impact of the addition Reference Alliance Standards Part 8 Section 8.1 Applicability of Building Code. Have provisions been made in floors or decks for a concentrated load (such as heavy equipment, water tanks, stored materials, etc) applied at a location wherever this load acting upon an otherwise unloaded floor would produce stresses greater than those caused by a uniform load? We observed water tanks on the roof with capacities ranging from 3,500 to 5,000 liters (925 to 1,320 gallons). Documentation could not be found to verify that the design of the building structure accounted for the loads applied by these tanks, and it is therefore likely that the roof structure at these locations is The Alliance for Bangladesh Worker Safety Page 5/11

6 subject to loads greater than that for which it was designed. Visual Assessment: Visual assessment of water tanks on roof top. Engage a qualified structural engineer to confirm and document that provisions have been made to accommodate concentrated loads. If provisions have not been made, have a qualified structural engineer develop a remediation plan. Alliance Standard Part 8 Section 8.13 and 8.14 Where density of operations, storage of materials, or equipment weights require live load capacity in excess of 2.0 kn/m2 (42 psf), do the design documents confirm that the required load capacity exists? Or has the load capacity been analytically confirmed and certified by an Alliance-qualified structural engineer? During our visual assessment, we did observe localized areas where the extent of stacked materials or equipment could potentially overload the floors. In these areas the floor structure may be subject to loads greater than that for which it was designed. These conditions, which occur in the Main Building, are summarized as follows: Floor 1: Empty cartons stacked on floor to heights of 8-0. Floor 1: Fabric storage stacked on racks. Additional areas of concentrated material storage and heavy equipment loads were observed on the ground floor. These include material storage, generator, boilers, compressors, and other mechanical equipment. In our judgment, the concrete slab on grade floor system employed on the ground level provides sufficient structural bearing capacity for these observed loading conditions. Visual Assessment: Visual assessment of overloaded areas. Have a qualified structural engineer confirm that capacity to support the load is available. Load Plans complying with Alliance Standard Part 8 Section should also be developed. Alliance Standards Part 8 Section 8.15 Minimum Floor Design Loads Are Certificates of Occupancy available for review? Certificates of Occupancy were not available for review. Document Review: Review of all available documents. The Alliance for Bangladesh Worker Safety Page 6/11

7 Provide Certificates of Occupancy for review. Alliance Standard Part 8 Section 8.3 Preliminary Structural Assessment Structural System Construction Is the structural system free of deflections (sagging), rotations (twisting), perceivable vibrations, or other noticeable movements of the structure? High The top sides of the ancillary building roofs in the complex were generally not accessible and therefore not visually observed. Access at Building 2 was prevented by the proximity of overhead power lines. Like the floor structures, the roof framing of these buildings was viewed with minimal to no obstructions from the floor immediately below. In this review we observed visible deflection in a portion of the Building 3 roof slab that cantilevers over the stair. While other signs of structural distress were not observed from below, in a condition such as this greater cracking would be expected on the top side of the slab, which was not accessible for visual observation. Visual Assessment: Visual assessment of Building 3 Have a qualified structural engineer provide further analysis and investigation of the visible deflection observed in the cantilever roof slab of Building 3 and other structural deficiencies. Structural engineer shall also provide remediation documents if Reference Alliance Standards Part 8 Structural Design Section 8.2 Structural Integrity of Existing Buildings Have all areas of needed maintenance, including areas with efflorescence, dampness, standing water on rooftops, and corrosion been addressed. We observed minor water ponding on the flat roof of the Main Building. Although not specifically observed, accumulated water can result in water intrusion into structural roof members (slabs, beams, etc.) that will promote corrosion of the reinforcing steel and deterioration of the concrete. Visual Assessment: Visual assessment of roof top. Under guidance from a qualified structural engineer, address all areas of needed maintenance by correcting the identified issues. The roof slope and The Alliance for Bangladesh Worker Safety Page 7/11

8 drainage system should be corrected as required to produce proper and timely drainage of the roof surfa Alliance Standard Part 8 Section 8.26 Durability and Maintenance Are any structural elements constructed with MCAC exposed to rainfall or other sources of water sealed with a protective coating to prevent water intrusion? As part of the follow up work by Shaheedullah (detailed elsewhere via the column FoS question) conducted following the site visit by Walter P Moore, it was determined that MCAC was used in the construction of the Building 3 columns but not the Building 1 columns. MCAC usage was not documented for the other elements such as the roof slabs. Visual Assessment: General Remark. If it is determined that MCAC was used in the construction of the roof or other concrete elements exposed to moisture, provide a protective coating at the structural elements constructed with MCAC exposed to rainfall or other sources of water. Have protec Alliance Standards Part 7 Building Materials Section 7.2 Masonry-chip aggregate concrete (MCAC). The exterior façade is free of cracking. In some locations nominal cracking was noted in the non-bearing masonry walls at the building perimeter. This cracking is not significant and should not be considered detrimental to the overall building structural stability. We did not observe any conditions at the facility where wall cracks indicated differential foundation settlement or other structural distress. Visual Assessment: Visual assessment of facade. Have a qualified structural engineer provide further analysis of the identified cracks to determine the appropriate course of corrective action. Alliance Standard Part 8 Section 8.2 The Alliance for Bangladesh Worker Safety Page 8/11

9 Structural Safety Programs Are floor loads in compliance with posted plans? Non-Compliance Level: 1 There are no posted load plans. Once plans are posted, redistribute floor loads to comply with the Floor Loading Plans. Alliance Standard Part 8 Section 8.10 Floor Loading Plans (Load Plans). Is a program in place to ensure that the live loads for which a floor or roof is or has been designed will not be exceeded? Non-Compliance Level: 1 There is not a program in place to ensure that the live loads for which a floor or roof is or has been designed will not be exceeded. Develop a program to ensure that all live loads for which a floor or roof has been designed for will not be exceeded. The designated Load Manager shall oversee this program and ensure it is enforced. Alliance Standard Part 13 Section 13.7 and Part 8 Section 8.9. Have Load Plans been prepared for each floor documenting the actual maximum operational loading that is intended and/or allowable on each floor. Load Plans have not been prepared for each floor documenting the actual maximum operational loading that is intended and/or allowable on each floor. Have a qualified structural engineer develop Floor Loading Plans per the requirements of Part 8 Section The Alliance for Bangladesh Worker Safety Page 9/11

10 Alliance Standard Part 8 Section 8.10 Floor Loading Plans (Load Plans) Are areas used for storage of work materials and work products, clearly marked to indicate the acceptable loading limits as described in the Load Plan for that floor? Areas used for storage of work materials and work products, are not clearly marked to indicate the acceptable loading limits as described in the Load Plan for that floor. Provide signage or the appropriate markings at all areas used for storage to indicate the acceptable loading limits detailed in the Load Plan. Alliance Standard Part 8 Section 8.11 Floor Load Markings Is a designated representative ( Load Manager), who is onsite full time, trained regarding the structural floor capacity, and serves as an ongoing vendor resource and monitor of operational factory floor loadings? There is not a designated representative ( Load Manager), who is onsite full time, trained regarding the structural floor capacity, and serving as an ongoing vendor resource and monitor of operational factory floor loadings. Designate a representative as the Load Manager. The Owner shall ensure that at least one individual, the Load Manager who is located onsite full time at the factory, is trained in calculating operational load characteristics of the Alliance Standards Part 8 Section 8.9 Load Manager Are Floor Load Plans posted as required? Non-Compliance Level: 1 The Alliance for Bangladesh Worker Safety Page 10/11

11 Floor Load Plans are not posted as required. Have a qualified structural engineer prepare load plans including the information required in Section 8.20 of the Alliance Standard. Alliance Standard Part 8 Section The Alliance for Bangladesh Worker Safety Page 11/11