BUILDING INTEGRITY SUMMARY REPORT

Transcription

1 BUILDING INTEGRITY SUMMARY REPORT SUPPLIER NAME Karnafuli Shoes Industries Ltd (Garments Unit) SUPPLIER ADDRESS Building No 17, Building No 16, Canteen Building No 2, Canteen Building No 1; Building No 11; Building No 12; ; Substation Building; Boiler Plant KEPZ; Anwara Chittagong; Bangladesh AUDIT DATE April 2016 AUDIT PERFORMED BY Department of Civil Engineering, Bureau of Research, Testing and Consultation, Bangladesh University of Engineering and Technology (BUET) AUDIT TEAM 2 auditors GRAVITY LOADING EVALUATION: Building No 17 The building is fully safe. Building No 16 Canteen Building No 2 Canteen Building No 1 Building No 11 Building No 12 SEISMIC PERFORMANCE RATING Building No 17 POOR Since pounding may occur between the steel shed and the Building No 16 POOR 3-storied RCC buildings, separation is recommended to be made between the main steel shed and its attached toilet units using independent columns, unreinforced masonry shear walls do not satisfy the mentioned requirement, possibility of out of plane failures of peripheral masonry walls and possibility of site amplification exists. Canteen Building No 2 FAIR DEA; Since there is marginal mass irregularity in the Canteen Building No 1 FAIR building, possibility of out of plane failures of peripheral masonry walls and possibility of site amplification exists. Building No 11 FAIR Since pounding may occur between the steel shed and the Building No 12 FAIR 3-storied RCC buildings, unreinforced masonry peripheral BUILDING INTEGRITY INSPECTTION SUMMARY I KSI I 1/10

2 FAIR walls do not satisfy the mentioned requirement, possibility of out of plane failures of peripheral masonry walls and possibility of site amplification exists. Substation Building FAIR Possibility of out of plane failures of peripheral masonry walls exists, possibility of liquefaction and amplification exist Boiler Plant FAIR DEA; Flexible coupling need to be provided for the entire stiff pipe systems at the bending points, chimney and other vertical elements need to be braced, possibility of out of plane failures of peripheral masonry walls exists. BRIEF DESCRIPTION OF METHODOLOGY Visual inspection and ASCE Tier-1 Analysis BUILDING INTEGRITY INSPECTTION SUMMARY I KSI I 2/10

3 DETAILED CONTENT VISUAL INSPECTION AND CONCLUDING REMARKS... 3 SEISMIC PERFORMANCE EVALUATION... 6 I. BASIC STRUCTURAL CHECKLIST NON-COMPLIANCES... 6 II. GEOLOGICAL SITE HAZARDS AND FOUNDATIONS CHECKLIST NON-COMPLIANCES... 7 III. BASIC NON-STRUCTURAL COMPONENT CHECKLIST NON-COMPLIANCES... 7 DETAILED DESCRIPTION OF METHODOLOGY... 8 VISUAL INSPECTION AND CONCLUDING REMARKS Building No 17 The typical grid spacing of the building X26.25 and supported by a 20 x20 column at the basement may be regarded as safe for its present level of use. Length of steel anchorage for at least three column pedestals has to be verified and reported, Toilet units constructed as attached with central steel shed (using common columns) is recommended to separate from the shed by constructing independent columns for the toilet units to improve seismic performance. Total story drift and inter storey drift for the steel shed and the two 3-storied RCC buildings need to be estimated and provided to the undersigned assessors, avoid out of plane failures during earthquakes. This shall be achieved within the next three months. Building No 16 The typical grid spacing of the building X26.25 and supported by a 20 x20 column at the basement may be regarded as safe for its present level of use. Length of steel anchorage for at least three column pedestals has to be verified and reported, Toilet units constructed as attached with central steel shed (using common columns) is recommended to separate from the shed by constructing independent columns for the toilet units to improve seismic performance. BUILDING INTEGRITY INSPECTTION SUMMARY I KSI I 3/10

4 Total story drift and inter storey drift for the steel shed and the two 3-storied RCC buildings need to be estimated and provided to the undersigned assessors, avoid out of plane failures during earthquakes. This shall be achieved within the next three months. Canteen Building No 2 The typical grid spacing of the building X24.60 and supported by a 18 x18 column at the ground floor may be regarded as safe for its present level of use. avoid out of plane failures during earthquakes. This shall be achieved within the next three months. Since there is mass irregularity in the building a detail engineering analysis (Tier-2) of the structure need to be carried out to assess the performance under the seismic load. Canteen Building No 1 The typical grid spacing of the building X24.60 and supported by a 18 x18 column at the ground floor may be regarded as safe for its present level of use. avoid out of plane failures during earthquakes. This shall be achieved within the next three months. Since there is mass irregularity in the building a detail engineering analysis (Tier-2) of the structure need to be carried out to assess the performance under the seismic load. Building No 11 The typical grid spacing of the RCC buildings X26.25 and supported by a 20 x20 column at the GF may be regarded as safe for its present level of use. Length of steel anchorage for at least three column pedestals has to be verified preferably by BUILDING INTEGRITY INSPECTTION SUMMARY I KSI I 4/10

5 NDT and reported, Total story drift and inter storey drift for the two 3-storied RCC buildings and top deflection of the steel shed need to be estimated and provided to the undersigned assessors, avoid out of plane failures during earthquakes. This shall be achieved within the next three months. Building No 12 The typical grid spacing of the RCC buildings X26.25 and supported by a 20 x20 column at the GF may be regarded as safe for its present level of use. Length of steel anchorage for at least three column pedestals has to be verified preferably by NDT and reported, Total story drift and inter storey drift for the two 3-storied RCC buildings and top deflection of the steel shed need to be estimated and provided to the undersigned assessors, avoid out of plane failures during earthquakes. This shall be achieved within the next three months. The typical grid spacing of the RCC buildings X26.25 and supported by a 20 x20 column at the GF may be regarded as safe for its present level of use. Length of steel anchorage for at least three column pedestals has to be verified preferably by NDT and reported, Total story drift and inter storey drift for the two 3-storied RCC buildings and top deflection of the steel shed need to be estimated and provided to the undersigned assessors, BUILDING INTEGRITY INSPECTTION SUMMARY I KSI I 5/10

6 avoid out of plane failures during earthquakes. This shall be achieved within the next three months. Substation The as built drawing of the building (along with element size and shape and reinforcement) has to be developed, Length of steel anchorage for at least three column pedestals has to be verified by NDT and reported, Also consecutive three footings at grid intersections B3, B4 and B5 or D3, D4 and D5 or F3, F4 and F5 or H3, H4 and H5 has to be Bracings need to be provided to all utility items which are hanging from the roof, the building, including building entrances and exits using FRP or by other means to avoid out of plane failures during earthquakes. This shall be achieved within the next three months. Boiler Plant Insufficient information for analysis, DEA is recommended. The as built drawing of the building (along with element size and shape and reinforcement) has to be developed, Length of steel anchorage for at least three column pedestals has to be verified by NDT and reported, The depth and size of footings for the chimney has to be Bracings need to be provided to the steam pipes and other utility items which are hanging from the roof, the building, including building entrances and exits using FRP or by other means to avoid out of plane failures during earthquakes. This shall be achieved within the next three months. SEISMIC PERFORMANCE EVALUATION I. BASIC STRUCTURAL CHECKLIST NON-COMPLIANCES Criteria Description of Conditions Comments Unit Building System-General The clear distance between the building The gaps between the two RCC Building No 17; being evaluated and any adjacent building buildings and the single-storied Building No 16; Adjacent Buildings shall be greater than 4 percent of the steel shed don t satisfy the Building No 11; height of the shorter building for Life condition of clear distance Building No 12; Safety and Immediate Occupancy. Configuration Mass There shall be no change in effective mass Change in effective mass Canteen Building BUILDING INTEGRITY INSPECTTION SUMMARY I KSI I 6/10

7 Concrete Moment Frames Shear Stress Check more than 50 percent from one storey to the next for Life Safety and Immediate Occupancy. Light roofs, penthouses, and mezzanines need not be considered. The shear stress in the unreinforced masonry shear walls, calculated using the Quick Check procedure of Section , shall be less than 30 psi for clay units and 70 psi for concrete units for Life Safety and Immediate Occupancy. (dead load) between adjacent stories is marginally higher than 50% Unreinforced masonry shear walls do not satisfy the mentioned requirement 2; Canteen Building 1 Building No 17; Building No 16; Building No 11; Building No 12; II. GEOLOGICAL SITE HAZARDS AND FOUNDATIONS CHECKLIST NON-COMPLIANCES Criteria Description of Conditions Comments Unit Slope Failure The building site shall be sufficiently remote from potential earthquake-induced slope failures or rock falls to be unaffected by such failures or shall be capable of accommodating any predicted movements without failure. The building is located adjacent to slopes. Boiler Plant III. BASIC NON-STRUCTURAL COMPONENT CHECKLIST NON-COMPLIANCES Criteria Description of Conditions Comments Unit Partitions Unreinforced Masonry Unreinforced masonry or hollow clay tile The height of unreinforced masonry wall at ground floor is Lighting Fixtures Emergency Lighting Stair Case URM Walls partitions shall be braced at a spacing equal to or less than 10 feet in levels of low or moderate seismicity and 6 feet in levels of high seismicity. Emergency lighting shall be anchored or braced to prevent falling during an earthquake. Walls around stair enclosures shall not consist of unbraced hollow clay tile or unreinforced masonry with a height-tothickness ratio greater than 12-to-l. A height-tothickness ratio of up to 15-to-l is permitted where only the Basic Nonstructural Component Checklist is required Mechanical and Electrical Equipment larger than 10 feet due to presence of tie beams. Emergency lighting is not securely fixed. The height-to-thickness ratio of URM walls is 13.2 where the thickness of wall is 10 inch. Building No 17; Building No 16; Building No 11; Building No 12; Building No 17; Building No 16; Building No 11; Building No 12; ; Sub-station Building; Boiler Plant Building No 17; Building No 16 BUILDING INTEGRITY INSPECTTION SUMMARY I KSI I 7/10

8 Attached Equipment Equipment weighing over 20 lb that is attached to ceilings, walls, or other supports 4 feet above the floor level shall be braced. External AC units may not be Building No 17; adequately braced. (Building No Building No 16; 17; Building No 16; Building No Building No 11; 11; Building No 12; Building No Building No 12; 13) External units may not be adequately braced. Sub-station Building; Boiler Plant DETAILED DESCRIPTION OF METHODOLOGY 1. The following criteria are used for the building integrity inspection: A. Permit review and verification. B. Visual assessment. C. Detailed assessment following ASCE-31 standards. i. Level of Investigation ii. Level of Performance Evaluation to Life Safety Performance Level (L.S.) iii. Level of Seismicity According to BNBC (1993) and based on geotechnical investigation report 1. Zone coefficient 2. Site Class (as per BNBC 1993) Design short period response acceleration S DS Design spectral response acceleration at 1 sec. SD 1 iv. Building Type v. Screening Phase (Tier 1) vi. Basic Structural Checklist BUILDING INTEGRITY INSPECTTION SUMMARY I KSI I 8/10

9 vii. Geological Site Hazards and Foundation Checklist viii. Basic Non-structural Component Checklist 2. Gravity Loading Evaluation Definitions YELLOW AMBER RED Factor of Safety (FS) of Column Strength is greater than the building is fully safe Factor of Safety (FS) of Column Strength is between 1.5 and the building is marginally safe Factor of Safety (FS) of Column Strength is between 1.25 and the building's safety is not fully ensured Factor of Safety (FS) of Column Strength is less than the building is unsafe 3. Seismic Performance Ratings ( ) GOOD FAIR POOR VERY POOR Buildings and other structures whose performance during a major seismic disturbance is anticipated to result in structural and nonstructural damage and/or falling hazards that would not significantly jeopardize life. Buildings and other structures with a GOOD rating would represent an acceptable level of earthquake safety, such that funds need not be spent to improve their seismic resistance to gain greater life safety. Buildings and other structures whose performance during a major seismic disturbance is anticipated to result in structural and nonstructural damage and/or falling hazards that would represent low life hazards. Buildings and other structures with a FAIR seismic rating would be given a low priority for expenditures to improve their seismic resistance and/or to reduce falling hazards so that the building could be reclassified GOOD. Buildings and other structures expected to sustain significant structural and nonstructural damage and/or result in falling hazards in a major seismic disturbance, representing appreciable life hazards. Such buildings or structures either would be given a high priority for expenditures to improve their seismic resistance and/or to reduce falling hazards so that the building could be reclassified GOOD, or would be considered for other abatement programs, such as reduction of occupancy. Buildings and other structures whose performance during a major seismic disturbance is anticipated to result in extensive structural and nonstructural damage, potential structural collapse, and/or falling hazards that would represent high life hazards. Such buildings or structures either would be given the highest priority for expenditures to improve their seismic resistance and/or to reduce falling hazards so that the building could be reclassified GOOD, or would be considered for other abatement programs, such as reduction of occupancy. BUILDING INTEGRITY INSPECTTION SUMMARY I KSI I 9/10

10 BUILDING INTEGRITY INSPECTTION SUMMARY I KSI I 10/10