BUILDING INTEGRITY DEA SUMMARY REPORT

Transcription

1 BUILDING INTEGRITY DEA SUMMARY REPORT SUPPLIER NAME UNITS AUDITED Opex Mills SSL2 Building 4X Generator Building 6X Generator Building Denim Generator Building Rope Denim Generator Building SSL Generator Building Generator Utility Building Diesel Generator Building Label Building SUPPLIER ADDRESS AUDIT DATE December 2014 AUDIT PERFORMED BY AUDIT TEAM Kanchipur,Narayangonj,Dhaka,Bangladesh Arko Consults Environment & Infrastructure Management Solution (EIMS) 4 Members including structural engineer. BUILDING OVERVIEW SSL 3 Garment Manufacturing RCC frame structure 2 story/ Sqft/floor. Floor Load Ground Floor: Spinning section, 1st floor: Spinning & Office. Isolated. Yes 4X GENERATOR BUILDING Utility Reinforced concrete structure Two storied / Total building area approx. 8,440 sft Ground floor: Generator 1st floor: Generator Main building part foundation is shallow foundation over 8" diameter sand pile. Extended part is over 18" diameter cast in situ single pile. BUILDING INTEGRITY DEA INSPECTION SUMMARY OPEX MILLS PAGE 1/10

2 6X GENERATOR BUILDING DENIM GENERATOR Utility Reinforced concrete structure Two storied / Total building area approx. 9,838 sft Ground floor: Generator 1st floor: Generator Footing on timber piles (6 in diameter according to the drawing) Utility RC beam column frame structure 3 story/ Sq.ft Ground floor : Boiler room and generator room 1 st floor: Substation, Power plant, Chiller room and store 2 nd floor : Compressor, Dryer and Store Roof: (4 Cooling Tower, Boiler silencer pipe and connecting pipe network for cooler. Cast -in-situ concrete pile. ROPE DENIM GENERATOR BUILDING Utility RC beam column frame structure 3 Story/13300 Sq.ft Ground floor : Generator room 1 st floor: Boiler and Chiller room 2 nd Floor: Compressor, Dryer and Control Panel Roof : Generator, Cooling Tower, 12 Chiller cooling tower and connecting pipe network for cooling tower. Cast -in-situ concrete pile. GENERATOR UTILITY BUILDING Garment Manufacturing BUILDING INTEGRITY DEA INSPECTION SUMMARY OPEX MILLS PAGE 2/10

3 RCC frame structure 2 story/ approx.3000 sq.ft/floor Ground Floor: Utility Maintenance Store, 1st floor: office Single and Combine footing DIESEL GENERATOR BUILDING Floor Load LABEL BUILDING Garment Manufacturing RC Frame structure 3 story/ approx.645 sq.ft/floor Ground Floor: Vacant, 1st Floor: Vacant, 2nd Floor: 01 Electric Control Panel Single and Combine footing Garments Label manufacturing Reinforced concrete beam-column frame structure Four storied / Total building area approx. 10,232 sft Ground & 1 st floor: label section 2 nd & 3 rd floor: compressors Individual footing on 6 dia, 23 to 25 long, Wooden Piles (as per drawing) BRIEF DESCRIPTION OF METHODOLOGY Detailed Engineering Analysis (DEA) as Bangladesh National Building Code (BNBC) BUILDING INTEGRITY DEA INSPECTION SUMMARY OPEX MILLS PAGE 3/10

4 DETAILED CONTENT Evaluation and Test... 4 Conclusion AND Recommendations..4 SSL3 Building 4&5 4X Generator Building 5 6X Generator Building 5 and 6 Denim Generator Building. 6&7 Rope Denim Generator Building 7 SSL Generator Building.. 7 and 8 Generator Utility Building. 8 Diesel Generator Building. 9 Label Building..9 DETAILED DESCRIPTION OF METHODOLOGY.10 EVALUATION AND TEST Destructive and Non Destructive Test o Evaluation of concrete strength from core test. o Verification of Rebar of structural members by Ferro Scanning Analysis of structural adequacy Assessment of Foundation Evaluation of Column Evaluation of Beams Evaluation of Slabs SSL 3: No diagonal cracks were observed in the partition walls due to differential settlement. Hence foundation is considered to be safe at prevailing load conditions. The columns are found safe in gravity loading for a live load of 5kN/sqmtr. For lateral (Earthquake and wind) load, members are found safe. Grade Beams are adequate under vertical load. Slabs interior panel are adequate. BUILDING INTEGRITY DEA INSPECTION SUMMARY OPEX MILLS PAGE 4/10

5 Recommendations: NIL 4X GENERATOR BUILDING: It was found that average concrete strength was 2080 psi and equivalent strength of concrete 1764 psi according to ACI 562. Considering both existing and BNBC recommended live load all the floor beams are adequate considering vertical load. However, most of the beams are overstressed due to lateral loading. Some grade beams are also overstressed. The slab is adequate for this loading condition. There is some crack observed in the ground floor roof slab which is may be due to the vibration of the equipment. Most of the columns are overstressed for gravity loading. Similarly, most of the columns are overstressed due to lateral loadings when both existing and BNBC recommended 63 psf is considered. Footings are adequate with factor of safety above 2.0 for existing loading and 63 psf live loading. All the pile capacity is adequate for existing loading and 63 psf live loading with factor of safety above 2.0. Recommendations: To ensure desired performance of the building structural members need to be retrofitted based on proper retrofitting design. Exterior beam and cracked portion of slab need to be repaired as per retrofit design. However during this rectification times equipment and electromechanical machineries need to be relocated or shut down for the safety of people at site 6X GENERATOR BUILDING It was found that average concrete strength was 2255 psi and equivalent strength of concrete 871 psi according to ACI 562. The slab is adequate for existing loading as well as for BNBC recommended 63 psf live load. BUILDING INTEGRITY DEA INSPECTION SUMMARY OPEX MILLS PAGE 5/10

6 For both existing loading and for BNBC recommended 63 psf live load all the floor beams in typical floor are adequate without considering lateral loadings. Considering lateral loading a few numbers of floor beams and grade beams are overstressed. Most of the columns are overstressed due to existing and 63 psf live loading loadings condition and almost all the columns are overstressed due to lateral loadings. All the pile capacity is adequate for existing loading with factor of safety above 2.0 except two pile group. All the foundations are adequate for 63 psf live load with factor of safety above 2.0 except two (F.S above 1.5). Recommendations: Proper anchorage of boiler base need to ensure by casting pedestal of boiler. R.C.C. casting with rebar encasement can be used to avoid future cracks due to temperature change or movement. BUET recommendation for unreinforced masonry should be followed. Slenderness ratio of the columns is very high it needs to be addressed during selection of suitable retrofitting period. Performance of the non-durable timer piles need to be assessed. Here, detail liquefaction potential was not calculated due to unavailability of soil parameter from soil test data supplied by client. However during this rectification times equipment and electromechanical machineries need to be relocated or shut down for the safety of people at site DENIM GENERATOR BUILDING Average concrete strength was found 3425 psi and equivalent strength of concrete 2300 psi according to ACI 562. Considering the concrete strength suggested by ACI 562, all the columns, slabs are adequate (without considering any lateral load). The slab is adequate for existing loading. All the floor beams in typical floor are adequate considering lateral loadings. Some grade beams are overstressed. Considering BNBC 2006 with all its load combinations (i.e. gravity and lateral load) most of the columns are overstressed in the ground floor level where floor height is 21'-0". All the columns are adequate for gravity loading except six double height columns out of twenty five columns. However, most of the columns are overstressed due to lateral loadings BUILDING INTEGRITY DEA INSPECTION SUMMARY OPEX MILLS PAGE 6/10

7 All the pile capacity is adequate for existing loading with factor of safety above 2.0 except one pile group (F.S above 1.5). Considering 63 psf live load, all the foundations are adequate for factor of safety more than 2.0 except one pile group (F.S above 1.5). RECOMMENDATIONS We recommend rectify the overstressed structural members by proper retrofitting method. However during this rectification times equipment and electromechanical machineries need to be relocated or shut down for the safety of people at site. Stair is found to be adequate from analysis and comparing with design. BUET recommendation for unreinforced masonry should be followed. ROPE DENIM GENERATOR BUILDING Equivalent concrete strength was found 2600 psi. The equivalent concrete strength has been calculated according to ACI 562. The slab is adequate for existing loading condition and BNBC recommended loads. Some floor beams are not adequate considering lateral loadings. All the columns are adequate for gravity loadings but most of the columns are overstressed due to lateral loadings. Stairs are found to be adequate considering field investigation and analysis. All the foundations are adequate for existing loading with factor of safety above 2.0. By observing the soil stratification of Bore hole No 34 and 36 for Rope Denim Generator Building we found that the liquefaction potential is absent at the site. RECOMMENDATIONS Overstressed Columns should be strengthened by proper retrofitting. Overstressed Beams should be strengthened. Restriction should be imposed on vertical extension of any storey. Brick work need to be strengthened to prevent out-of-plane failure by providing vertical support or wrapping with FRP as per BEUT recommendation. SSL GENERATOR BUILDING BUILDING INTEGRITY DEA INSPECTION SUMMARY OPEX MILLS PAGE 7/10

8 It was found that the equivalent concrete strength for brick chips is 2,167 psi. The equivalent concrete strength has been calculated according to ACI 562. All beams are adequate for both existing and BNBC 2006 live loading which includes lateral load (i.e. earthquake and wind load). However, some beams at first floor are overstressed for torsion which can be neglected. All the columns are adequate for gravity loadings. However, some columns at ground floor are overstressed due to lateral load for both existing and BNBC 2006 live loading condition. The slab is adequate for all loading condition. However at first floor, deflection under compressor is a concern issue and significant vibration found due to compressor. Pile foundations are adequate for all loading conditions. RECOMMENDATIONS We recommend to strengthen the overstressed structural members with proper retrofitting design. Moreover, need to reduce load on first floor if possible and need to incorporate damping device with proper design under base of the compressor to reduce vibration. GENERATOR UTILITY BUILDING Structure was analyzed under actual present loading conditions and under BNBC 2006 loading conditions. Under vertical loading, for a live load of 3.0 kn/sqm, the building is found safe. Under lateral (earthquake & Wind) load, members are found safe. Foundation is considered safe at prevailing loading condition. Beams are adequate under vertical load & lateral load. No cracks were detected. Grade Beams are adequate under vertical load. Slabs interior panel are adequate. No significant deflections were detected. Recommendations: Nil BUILDING INTEGRITY DEA INSPECTION SUMMARY OPEX MILLS PAGE 8/10

9 DIESEL GENERATOR BUILDING Structure was analyzed under actual present loading conditions and under BNBC 2006 loading conditions. Under vertical loading, for a live load of 2.0 kn/sqm, the building is found safe. Under lateral (earthquake & Wind) load, some members are found overstressed. Foundation is considered safe at prevailing loading condition. Beams are adequate under vertical load & lateral load. No cracks were detected. Grade Beams are adequate under vertical load. Slabs interior panel are adequate. No significant deflection were detected. Recommendations: Recommended to retrofitting of lateral load (Earthquake and Wind) within 9 months. LABEL BUILDING Stone chips was used in ground floor and brick chips was used from 1 st floor. We found equivalent concrete strength for stone chips is 2210psi and 2945 psi for brick chip. The equivalent concrete strength has been calculated according to ACI 562. The two way beam supported slab is adequate for both existing loading condition considering both existing and BNBC recommended 63 psf live load. All the grade beams section sizes are adequate. However, provided reinforcement at support is less than the required amount at most of the positions. For existing all the columns are adequate except 10 for gravity loading condition. However, most of the columns are overstressed due to lateral loadings. For 63 psf live load most all the columns are overstressed both in gravity loading and lateral loadings. All the foundations are adequate for existing loadings with factor of safety above 1.5 except six. Recommendations: We recommend to strengthening the overstressed structural members with proper retrofitting design. BUILDING INTEGRITY DEA INSPECTION SUMMARY OPEX MILLS PAGE 9/10

10 DETAILED DESCRIPTION OF METHODOLOGY Specification for Detail Structural Assessment Structural Analysis will be carried on according to BNBC (1993) and ACI code. I. Testing of Materials: Sub-soil Investigation Core/Pullout/CAPO Test (Destructive Test) for Concrete Strength UPV (Ultrasonic Pulse Velocity) Test (Non-destructive Test) for Concrete Strength Ferro-Scanning in Column, Beam and Slab for Rebar Detection. II. Investigation of Foundations Foundation Explorations III. Structural Evaluation (Design check): Analysis of sub-soil investigations report Development of computer simulated model Checking of structural stability and geometry Checking adequacy of foundation i.e. pile & pile cap or footing/raft Checking of lateral load resistance capacity of the Building BUILDING INTEGRITY DEA INSPECTION SUMMARY OPEX MILLS PAGE 10/10