Structural Inspection Report Victory Knittings (PVT) Ltd.

Category RED
Revision: Issue 1
Date: 9th June 2104
Victory Knittings (PVT) Ltd.
Ltd
63/1, BB Road, RAJUK plot no-24, Narayanganj, Bangladesh.
(23.612038N, 90.502462E)
4th June 2014
Structural Inspection Report
Observations & Actions
Authors: Salam Al Sabah, Sebastian Kaminski
Checked by: Peter Flynn & Aidan Madden
Approved by: Peter Flynn
1
Executive Summary
On Wednesday 4th June 2014 Mr Salam Al-Sabah and Mr Sebastian Kaminski of Arup carried out
a visual structural survey of the Victory Knittings (PVT) Ltd. factory at the coordinates given on
the cover page of this report. We met with the Chairman Mr Md. Abu Hanif Bhuiyan, the
Managing Director Mr A. K. M. Zahidul Hoq Bhuiya, and the Director Mr A. K. Zamirul Hoq
Bhuiyan. The General Manager was in his position since 1993. The building was built in two
stages. The first in the early 80s where the first three storeys, and the second in 1993 when the
top 3 storeys where built. The company occupied the top three floors of this building since 1993.
The other three storeys are occupied by offices, shops, storage rooms for the factory, an
apartment, and a doctor's clinic. The generator is located at the ground floor on the East side of
the building. The site was reported by the Managing Director to have no flooding history. The
factory employs around 125 workers and produces to many brands. Some of the leading brands
are Hunkemull and VND. The building is owned by Mr Reazul Hoq Chowdhury.
The building has a reinforced concrete structure made from slabs supported on beams and
columns that are supported by pad foundations. Lateral stability is achieved through moment
frame action of the reinforced concrete frame. The brick infill panels can provide a additional
lateral resistance, however, no positive connection between the brick infill and the reinforced
concrete frame was observed. As a result it is not possible to assess the additional resistance
provided by the brick infill.
2
Executive Summary (Continued)
The building roof has a rectangular reinforced concrete tank, a group of four toilets, and a dining
shed with brick walls and a lightweight roof made from light corrugated metal sheets supported
on steel trusses which were supported on the external walls and internal steel columns. Some of
the trusses and their connections seemed to be non-engineered. The rooftop additions were not
shown on the Permit Drawings.
There is a noticeable deterioration visible on the building exterior. Concrete is spalling in many
locations and some plain reinforcement bars are visible.
During the pre-survey meeting we were presented with a collection of drawings and documents
including the Building Permit drawing approved by RAJUK in November 1980, and the Industrial
Permit issued in February 2009. The RAJUK Building Permit was issued for a FIVE storey building
rather than the six storey building that was actually built. Apart from the RAJUK Building Permit
drawing which showed a section in a pad foundation, no other structural drawings were
available.
A copy of the Soil Report for the site of the building was presented. It was issued by A+GEOTECH,
and was signed by Engineer Rafiqul Islam Bhuiyan (M-11528). The reason given by the Owner for
the late date of the Soil Report was that the original report could not be found and that required
the commissioning of a new one. The report gave the option of having a shallow isolated footing
or piled foundation. No material test certificates were presented and no floor loading plans were
provided.
3
Executive Summary (Continued)
The information shown on the drawings presented was generally found to be in line with the as
constructed building. However inconsistencies, including the additional floor, were noted and
these are referenced in the observation section of this report.
Overall, only limited structural drawings and information are available. There was no information
on column grid or size, nor on reinforcement.
While the primary structure of the building appears to be generally in good structural condition,
we do have important and urgent concerns in relation to the adequacy of the internal columns
throughout the building. These concerns need to be addressed immediately, which give rise to
our recommendation for an Immediate Evacuation.
The principal reasons for our concern is that the internal columns, throughout the building,
appear to be stressed to extremely high levels that require the immediate evacuation. The
attempts to reduce column stress to acceptable values, including reduced or removal of load, did
not reduce column stress to an acceptable level.
4
IMMEDIATE EVACUATION
Columns in shaded zone are very
highly stressed.
Immediate Action Required
5
Executive Summary (Continued)
Additional observations were recorded and these are listed in the observations and actions
sections of this report.
A high level and non exhaustive list of key concerns are:
•
•
•
•
•
High column stresses throughout building
Slabs loaded by heavy uncontrolled loads
Water causing corrosion and spalling
Apparently non-engineered steel staircase
Absence of Structural Information And Inconsistencies Noted Between Drawings and As Built
Construction
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 of collapse in a
major Seismic event.
6
Building Extents
7
Victory Knittings
(PVT) Ltd.
Site Location Map
Building Extents
Victory Knittings (PVT) Ltd. - Factory Layout
(Extracted from Industrial Permit drawings dated
February, 2009)
Main factory building(6 storey)
9
Building Extents
10
West Elevation
West Elevation
East Elevation
East Elevation
Building Extents
Used solely by the Garment
ROOF
Dining Shed
5F(Not Permitted by RAJUK but
added in 1993)
Sewing Section
4F
Cutting Section
3F
Finishing, Store, Office
2F
Commercial Offices
1F
Market, Residences ,Doctor
Camber, Storage(Garment)
GF
Market, Warehouse &
Generator(Garment)
Current Use of Factory Floors
Building Extents
Dining, Prayer, Toilet >25% is
open
Structural Systems
12
1st Three floors were constructed in
1980
Rest 3 floors and the roof shed were
added later in 1993
Typical Floor Layout (Extracted from Industrial Permit drawings dated
February, 2009)
Structural System – Factory Building
Cantilevers on West and East Facade
Structural Systems:
RC Beam & Column with a 2-way
slab.
Lateral stability is assumed to be
provided by a combination of
moment frame and brick infill panels
acting as shear walls.
Multipurpose(Factory, Commercial, Residential) 6 storey
Building
Grid size : 4.40x4.49m (Typical
Internal)
Columns : 250 mm x 250 mm
RC(Typical Internal and External)
Beams: 270x270 mm (D/S)
Typical Floor Layout(Extracted from Industrial Permit drawings dated
February, 2009)
Slab thickness: 180 mm with finishes
(Average)
Floor to Ceiling Height: 3.20m
(Average)
Concrete aggregate: Brick
Structural drawings indicate pad
foundations(Which is also
recommended in Soil test report
dated October, 2011)
Structural System – Factory Building
Dining & Prayer Shed(Light
weight roof(roof truss,
corrugated tin sheet as roof,
bamboo mats supported on
brick infill panels on perimeter
and inside)
Toilet Shed(Light weight
roof(corrugated tin sheet
as roof, timber framing
supported on brick infill
panels on perimeter and
inside)
Roof Layout(Extracted from as industrial permit drawings
dated February, 2009)
Structural System – Factory Building
Water Tanks (Plastic one
on an elevated Solid Slab
in the front and Masonry
one which has corrugated
tin sheet as roof with
timber framing system and
brick walls on perimeter
with 125 mm built solid
slab on bottom)
Typical Floor Layout
Typical Floor Layout
Typical Floor Layout
Typical Floor Layout
Structural System – Factory Buildings
Cantilevers on West and East Facade
Typical Floor Cantilever
Typical Floor Cantilever
Structural System – Factory Buildings
Observations
18
Observations
High column stresses throughout building
19
Observations
All columns and slabs show brick aggregate
was used along with mild steel
High column stresses throughout building
20
Observations
Roof
4
3
2
1
GF
Original permit drawings were for 5 suspended
floors only, however building shows 6
High column stresses throughout building
21
Roof
5
4
3
2
1
GF
Observations
Slabs loaded by heavy uncontrolled loads
22
Observations
50kg bags of
cotton
equivalent to
8kpa over an
area of:
~ 10 m x 10 m
Loose clothing
up to 3m high,
equivalent to
5kpa over an
area of:
~ 5 m x 10 m
Full height
masonry walls
Up to 500 mm
local buildups
under toilet
blocks
Slabs loaded by heavy uncontrolled loads – factory unaware of load capacity of slab
23
Observations
Water causing corrosion and spalling
24
Observations
Wind posts:
spalling of
concrete and
corrosion of steel
Downstand
beams: spalling
of concrete and
corrosion of
steel
Water causing corrosion and spalling
25
Observations
Apparently non-engineered steel staircase
26
Observations
Steel staircase to North West
Apparently non-engineered steel staircase
27
Supports and entire structure
appears non-engineered
Observations
Apparently non-engineered steel roof structures
on roof
28
Observations
Canteen to South – roof truss and
columns appear non-engineered
Toilet block to North – roof structure
appears non-engineered
Steel roof structures on roof – apparently non-engineered
29
Observations
Absence of Structural Information And
Inconsistencies Noted Between Drawings and As
Built Construction
30
Observations
Beams missing
and alternative
beams and
columns in place
Staircase to North
West missing from
drawings
Staircase to East
different from
drawings
Slab shown as 100mm
thick on drawings,
appears thicker
Roof
structures
missing from
drawings
Absence of Structural Information And Inconsistencies Noted Between Drawings and As
Built Construction
31
Priority Actions
32
Problems Observed
ITEM 1:
ITEM 2:
ITEM 3:
ITEM 4:
ITEM 5:
ITEM 6:
33
High column stresses throughout building
Slabs loaded by heavy uncontrolled loads
Water causing corrosion and spalling
Apparently non-engineered steel staircase
Apparently non-engineered steel roof
structures on roof
Inconsistencies Between Drawings and As
Built Construction
Item 1 and actions
High column stresses throughout building
Priority 1
•
Evacuate building
•
Detailed Engineering Assessment of as built structure to be
commenced as per attached scope
•
Strengthen building as appropriate
(Immediate - Now)
Priority 2
(within 6-weeks)
Priority 3
(within 6-months)
34
Item 2 and actions
Slabs loaded by heavy uncontrolled loads
Priority 1
•
Limit live load on all
floors to 2kPa
•
•
•
•
Detailed Engineering Assessment of as built structure to be
commenced as per attached scope
Verify insitu concrete strengths of floor plates by cores.
Verify reinforcement within beams and slabs
Produce and actively manage a loading plan for all floors within
the building giving consideration to floor capacity and column
capacity
•
Continue to implement load plan
(Immediate - Now)
Priority 2
(within 6-weeks)
Priority 3
(within 6-months)
35
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-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
36
Item 3 and actions
Water causing corrosion and spalling
Priority 1
•
None required
•
None required
•
Engineer to inspect damaged concrete elements and propose
a suitable repair
(Immediate - Now)
Priority 2
(within 6-weeks)
Priority 3
(within 6-months)
37
Item 4 and actions
Apparently non-engineered steel staircase
Priority 1
•
None required
•
None required
•
Steel staircase should be designed and upgraded to
support code vertical loads by the building Engineer, or it
should be vacated and removed
(Immediate - Now)
Priority 2
(within 6-weeks)
Priority 3
(within 6-months)
38
Item 5 and actions
Apparently non-engineered steel roof
structures on roof
Priority 1
•
None required
•
None required
•
Roof structures should be designed and upgraded to
support code vertical and horizontal loads by the building
Engineer, or they should be vacated and removed
(Immediate - Now)
Priority 2
(within 6-weeks)
Priority 3
(within 6-months)
39
Item 6 and actions
Inconsistencies Between Drawings and As Built
Construction
Priority 1
•
None required
•
None required
•
Building Owner to engage an Engineer to carry out As Built
survey of building and produce accurate complete as-built
drawings
(Immediate - Now)
Priority 2
(within 6-weeks)
Priority 3
(within 6-months)
40
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. Structural Engineering to be undertaken by a suitably
qualified Engineer who meets the competency guidelines in the BUET developed Tripartite Guideline document for Assessment of Structural Integrity
of Existing RMG Factory Buildings in Bangladesh.
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.
41