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10 Reasons of Collapse

of

Feature WallAt Anushriya Villa, Noida Sector 128

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COVER NOTE

Structural Failures occur due to a combination of reasons.

Structures are anyways designed with factors of safety, by all structural consultants,

So, a failure of this type, is due to many factors, which work in tandem.

Our team visited site the same day (May 16) when the client informed us of the wall

Failure. What the team found was that the structural failure was cased due to lack of

Basic structural norms being followed, despite intimations on several past occasions.

The details hereunder have been put together methodically to explain and pinpoint the

Cause of the failure on faulty workmanship and lack of procedural norms in civil const-

Ruction.

The following slides are easy to understand and can establish without any doubt that

The civil contractor and supervisor need to be pulled up.

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Drawing Title: Feature Wall Column and Beam DetailDate of Issue: 10thSep. 2012

This is the Structural Drawing showing details of Structural members for the said wall.

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This is the Architectural Drawings for the said wall showing all structural members in elevation.

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Proposed Foundation Design

of the Feature wall, which is

showing it starting from1metre below the Natural

Good earth Level.

The executed foundation to

be re-excavated & checked /

verified for adherence to this

drawing.

There are serious doubts of

unsettlement in this

foundation, due to

foundations not being on

compacted earth, as per

norms. Also the grade of

concrete used therein, may

need to be examined at a lab

to see if it matches norms.

1. The FOOTINGS

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ON SITE STATUS

Photograph taken on 31st

Aug. 2012.

Earth Filling where the

Feature wall to come is

half done without proper

Compression of soil.

Good Earth is far below

this filling, from where

the foundation wasproposed.

This leads to the doubt in

Slide 1.

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Proposed Column detail

and Elevation with all the

structural members &

levels marked, can be

seen.

Please note there are 4

columns proposed and

several tie beams

between columns and to

the 90 Degree adjacent

wall.

Drawing Title:

Feature Wall Column & Beam Layout

Date of Issue: 10thSep. 2012

2. Number of

Columns & Tie Beams

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Photograph taken on 15th

May. 2013.

a. Shocking to note even

plaster is intact and no tie

up, even in brick work, is

visible; also no bar

connectivity with existing

columns is visible.

b. Site showed ONLY THREE,

instead of FOUR Columns

proposed.

c. One of these 3 Visible

Columns was wrongly

erected from above the

Plinth beam, WITHOUT

necessary foundation.

ON SITE STATUS

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Photograph taken on 15thMay.

2013

a. Plinth Beam not connected

with Existing Column

b. Plinth beam level is not as

per drawing . Top of plinth

beam and internal road levelshould match as per drawing.

WITHOUT THESE THE WALL

WOULD ALWAYS SHEAR AWAY

& FALL.

3. No PLINTH BEAM

with Adjacent wall

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Photograph taken on 15th

May. 2013

1. Plinth beam

terminates here. Not

connected with

Existing Column

2. The weight seems to

be on a brick

foundation that was

hastily made; but as

mentioned earlier,excavation would

need to be done, to

know the exact

picture.

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Photograph taken on 15th

May. 2013

All overlaps of steel rods

in column placed at same

place, contrary to the

norms that overlapping

should be at different

places for proper

strength.

This explains how thecolumns have separated

so easily, as encircled and

shown here.

4. Reinforcement

against Structural

Norms

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Photograph taken on 15th

May. 2013

Forget Rod Lapping not

done here. .. The fact is

that there is NO

CONNECTION at all.

With an inexplicable gap

of 6 atleast between the

two rods!

This is not at allacceptable and is a

serious breach of

established norms.

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Photograph taken on 15th

May. 2013

Ring distance and

overlapping are uneven

and deviated from

drawings. 150mm c/c

In some cases, it is

200mm and in some

more Proper chiselling

of concrete will show theexact spacing.

These appear to be

methods of saving cost

and steel, at the cost of

structure.

5. Ring Distance not

as per norms

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Photograph taken on 15th

May. 2013

Ring Distance and Main

Vertical rods distance not

as per drawings.

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Photograph taken on 15th

May. 2013

Steel development length

where column meet

beam not provided as per

norms.

This results in weakness

at joints and ease of

shearing off, resulting in

structural failure.

6. No Steel

development

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Photograph taken on 15th

May. 2013

Middle Beam, on

Adjacent wall, was not

connected properly with

the Existing Column.

Picture shows that

middle beam was merely

touching the Adjacent

wall. No hooking or

welding of steel

reinforcement at all

noticed; maybe wire or

even that was not used.

7. Middle beam not tied up.

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Photograph taken on 15thMay. 2013

Top Beam was not

connected properly with

the Existing Column and

Beam.

Picture shows that no rod

extension provided and

lapped with the adjacent

wall.

8. Top beam not tied up

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This is the Column detail

as per drawing issued.

Please Note: This tie rod

is missing in Column

reinforcement, in some

places.

Drawing Title: Feature Wall Column and Beam Detail

Date of Issue: 10thSep. 2012

9. The Tie rod Missing

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Photograph taken on 15th

May. 2013

Apart from structural RCC

issues, the contained infill

brickwork is also not

acceptable.

Material cement : sand ratiois not at all proper, as visible.

Curing not done at all,

apparently, as all bricks

appear to have separated

from each other very simply.

Also, note that the Concrete

quality is very poor. Lab

analysis of this may be done

to analyse crushing strength.

10. No Curing

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Contractors will always want to cut corners and find ways of saving money.

Apart from this, all the evidence shows that there was:

1. Lack of Supervision at Site During execution.

(It Has been always suggested & advised, by us often, to appoint dedicated Project

Managers / Supervisors)

2. Poor workmanship and lack of acceptable level of expertise in Construction

(An on site engineer would have ensured the basics of construction are enforced)

3. No attention was paid to Curing of the Structure during and after the construction.

(Attachment and sense of ownership to project may be lacking due to constant

useage of different teams and labour contractors)

4. Cost Constraints given to Contractors, as informed by contractors, on site.

(This results in compromise in cement sand mixes, steel, curing and several other

malpractices)

5. Non adherence to and / or Comprehension of the Drawings, provided.

The End Note