Abanti Color Tex Ltd. Plot-S, A-646, Shashongaon Enayetnager, Fatullah, Narayangonj ( E, N) 28 June 2014

Transcription

1 1 Abanti Color Tex Ltd. Plot-S, A-646, Shashongaon Enayetnager, Fatullah, Narayangonj ( E, N) 28 June 2014

2 2

3 Preliminary calculations suggest columns in Units 1 and 2 are highly stressed 3

4 Preliminary calculations based on observations suggest that a large number of columns in Unit 1A and 2 are highly stressed. Apparent horizontal crack observed in Unit 1A internal column C5, at ground floor 4

5 Punching shear stresses appear to be high in Unit 1 flat slabs 5

6 Preliminary calculations suggest that punching shear stresses in the suspended flat slabs in Unit 1A and 1B are high. No shear reinforcement was noted on the structural drawings provided. 6

7 Industrial loading above Unit 1B Basement causing extensive cracking 7

8 Unit 1B Full depth flexural cracks observed in basement beams, below industrial loading above 8

9 Slender RC column appears to be buckling in Unit 1D 9

10 Mid-height crack and bowing observed in slender RC column RC column 280x280 plastered 250x250 concrete. Height approx. 6m from GF Unit-1D 10

11 Uncontrolled and high loading observed in Unit 1A causing cracking below 11

12 Local high loading on 6th Floor LL 3.5kPa LL 5kPa Cracking observed to soffit below Blockwork walls 12 LL 3kPa * LL = Live Load LL 5kPa

13 Evidence of widespread soffit cracking to underside of 6 th floor slab beneath high load above 13

14 Inconsistencies between documentation and observations on site 14

15 The top storey of Unit 1A was not noted on the structural drawings provided No structural documentation was provided for Units 1B, 1C and 1D

16 Structural drawings provided for the ETP describe a 5 storey building

17 17 Priority Actions

18 Problems Observed ITEM 1: ITEM 2: ITEM 3: ITEM 4: ITEM 5: ITEM 6: High column stresses noted in Unit 1 and Unit 2 Punching shear stresses in Unit 1 flat slabs appear high Industrial loading above Unit 1B Basement causing cracking below Slender RC column appears cracked and bowing in Unit 1D Uncontrolled and high loading observed in Unit 1A Inconsistencies between documentation and observations 18

19 Item No. Observation Recommended Action Plan Recommended Timeline 1 High column stresses noted in Structural Engineer to review design, loads and columns Unit 1 and Unit 2 stresses Immediate - Now 2 High column stresses noted in Commence Detailed Engineering Assessment for Unit 1 and Unit 1 and Unit 2 Unit 2 see attached scope Immediate - Now 3 Verify insitu concrete strength either by taking 100mm dia. High column stresses noted in cores from 4 No. typical/non-critical columns or by using Unit 1 and Unit 2 existing cylinder strength data if available. Immediate - Now 4 Produce and actively manage a loading plan for all floor High column stresses noted in plates within the factory giving consideration to floor Unit 1 and Unit 2 capacity and column capacity. 5 High column stresses noted in Detail Engineering Assessment to be completed Unit 1 and Unit 2 6 High column stresses noted in Commence action on any recommendations arising from Unit 1 and Unit 2 the Detailed Engineering Assessment. 7 High column stresses noted in Continue to action recommendations arising from Detailed Unit 1 and Unit 2 Engineering Assessment 6-months 8 High column stresses noted in Continue to implement loading management plans Unit 1 and Unit 2 6-months 19

20 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 Elevational 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 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. 20

21 Item No. Observation Recommended Action Plan Recommended Timeline 9 Punching shear stresses in Unit 1 flat slabs appear high Commence a Detailed Engineering Assessment for Unit 1 as per Item 1 Immediate - Now 10 Punching shear stresses in Unit 1 flat slabs appear high Structural Engineer to review design, loads and punching shear stresses in slabs. Immediate - Now 11 Punching shear stresses in Unit 1 flat slabs appear high Verify insitu concrete strengths (using minimum of 4 No. 100mm dia. cores taken from slabs). Verify existing reinforcement (steel grade, bar diameter and spacing) in slabs. Immediate - Now 12 Punching shear stresses in Unit 1 flat slabs appear high Detailed Engineering Assessment to be completed 13 Punching shear stresses in Unit 1 flat slabs appear high Commence action on any recommendations arising from the Detailed Engineering Assessment. 14 Punching shear stresses in Unit 1 flat slabs appear high Continue to implement floor load plans 6-months 15 Punching shear stresses in Unit 1 flat slabs appear high Continue to action recommendations arising from Detailed Engineering Assessment 6-months 21

22 Item No. Observation Recommended Action Plan Recommended Timeline 16 Industrial loading above Unit Sections of plaster finish / paint to beams and slabs to be 1B Basement causing cracking removed to investigate if cracks penetrate the building below structure. Immediate - Now 17 Structural Engineer to specifically consider the slab and Industrial loading above Unit beam capacity of the ground floor, considering the actual 1B Basement causing cracking loads applied from washing and dyeing plant as part of the below Detailed Engineering Assessment. 18 Industrial loading above Unit Produce and actively manage a loading plan for the area 1B Basement causing cracking above the basement, giving consideration to floor capacity below and column capacity 19 Industrial loading above Unit 1B Basement causing cracking Continue to implement floor load plans below 6-months 20 Slender RC column appears cracked and bowing in Unit 1D Commence a Detailed Engineering Assessment as per Item 1 Immediate - Now 21 Slender RC column appears cracked and bowing in Unit 1D Structural Engineer to verify that column slenderness has been taken into account during design and validate as-built condition as part of the Detailed Engineering Assessment 22 Slender RC column appears cracked and bowing in Unit 1D Propose (and have installed) any retrofitting or strengthening required 22

23 Item No. Observation Recommended Action Plan Recommended Timeline 23 Uncontrolled and high loading observed in Unit 1A Commence a Detailed Engineering Assessment for Unit 1 as per Item 1 Immediate - Now 24 Uncontrolled and high loading observed in Unit 1A Produce and actively manage a loading plan for all floor plates within the factory, giving consideration to floor capacity and column capacity as part of the Detailed Engineering Assessment. 25 Uncontrolled and high loading observed in Unit 1A Continue to implement floor load management plans 6-months 26 Inconsistencies between documentation and observations Undertake a Detailed Engineering Assessment for Units 1 and 2 as per Item 1 Immediate - Now 27 Inconsistencies between documentation and observations As part of the Detailed Engineering Assessment, Structural Engineer to verify that the additional undocumented 11th floor of Unit 1A can be accommodated by the structure below 28 Inconsistencies between documentation and observations Building engineer to check, collect information and produce accurate and complete as-built documentation for all buildings 23