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Failure of elevated water tanks supported on shaft staging

 
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uhvaryani
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Joined: 21 May 2008
Posts: 249

PostPosted: Tue Jan 22, 2019 9:30 am    Post subject: Failure of elevated water tanks supported on shaft staging Reply with quote

Dear Sefians,    In the book "Learning from Failures" (1987) by late Er.R.N.Raikar,there are given
some photos of failure of these structures.These shafts get sunk in the ground.A few years back,a similar failure occurred in NOIDA,when one engineer and some other persons were killed.I had then written a paper on this subject,in the journal
Civil Engineering and Construction Review,October 1999.
   Why should these failures occur? I discussed this issue with some of my engineer-friends.I am surprised to know that not many engineers are aware of these failures,not to speak of the reasons thereof.Many engineers believe that
these shafts get sunk in the ground because of poor soil.It is not so at all.The failure occurs because of local buckling of thin shaft circular wall.There is a huge load of self-weight of concrete water tank and the load of water contained in the tank.This huge static load becomes dynamic,when the crippling of the shaft wall takes place due to local buckling of the thin circular wall.Then shaft pierces the raft foundation below it and goes down in the ground in the same way as a caisson is pushed down in the ground.
    Surprisingly,there is no mention of local buckling of these structures in the Code IS: 11682-1985, and also no mention in text-books by P.Dayaratnam(1992),N.K.Raju(1988) and S.K.Mallick and A.P.Gupta(1996).
Buckling phenomenon,be it global or local,is a tricky affair in compression members and it leads to failure,if not recognised.
     I request all sefians to share their experiences and ideas on this subject in the Forum,
with best wishes and regards,
uhvaryani

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sktrisal
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PostPosted: Tue Jan 22, 2019 2:30 pm    Post subject: Failure of elevated water tanks supported on shaft staging Reply with quote

A similar failure occurred in  greater noida factory of Daewoo  it was designed by s k nandi  of cp kukreja the shaft wall was thin and got further depleted by providing inserts for steps there were many casualities. Th e buckling of shaft has to be guarded.Sktrisal
9910416668


On Tue, 22 Jan 2019, 16:35 uhvaryani <forum@sefindia.org (forum@sefindia.org) wrote:

Quote:
           Dear Sefians,    In the book "Learning from Failures" (1987) by late Er.R.N.Raikar,there are given
some photos of failure of these structures.These shafts get sunk in the ground.A few years back,a similar failure occurred in NOIDA,when one engineer and some other persons were killed.I had then written a paper on this subject,in the journal
Civil Engineering and Construction Review,October 1999.
   Why should these failures occur? I discussed this issue with some of my engineer-friends.I am surprised to know that not many engineers are aware of these failures,not to speak of the reasons thereof.Many engineers believe that
these shafts get sunk in the ground because of poor soil.It is not so at all.The failure occurs because of local buckling of thin shaft circular wall.There is a huge load of self-weight of concrete water tank and the load of water contained in the tank.This huge static load becomes dynamic,when the crippling of the shaft wall takes place due to local buckling of the thin circular wall.Then shaft pierces the raft foundation below it and goes down in the ground in the same way as a caisson is pushed down in the ground.
    Surprisingly,there is no mention of local buckling of these structures in the Code IS: 11682-1985, and also no mention in text-books by P.Dayaratnam(1992),N.K.Raju(1988) and S.K.Mallick and A.P.Gupta(1996).
Buckling phenomenon,be it global or local,is a tricky affair in compression members and it leads to failure,if not recognised.
     I request all sefians to share their experiences and ideas on this subject in the Forum,
with best wishes and regards,
uhvaryani
     



     



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PostPosted: Tue Jan 22, 2019 2:53 pm    Post subject: Failure of elevated water tanks supported on shaft staging Reply with quote

Dear Mr Varyani

IS : 2210 &ndash; 1988, Cl. 9.3.1 provides a check for buckling stress in cylindrical shells. You are right that no text book explains complete design of elevated tank, particularly on shaft type staging. It becomes dangerous when an inexperienced engineer designs such type of structures following the text book, without having in depth knowledge about probable failure criteria for that type of structure and codal checks to prevent such failures. We have been designing elevated tanks with shaft type staging, while applying very first check on shaft thickness for buckling. Shaft section with openings / cut outs (for doors, pipes etc) shall become critical for buckling. Many a times shaft thickness is required to be increased to avert buckling, even though all other stresses are within permissible limits.

Regards.

Jayant Lakhlani
For
Lakhlani Associates
--(URL Auto Removed)

From: uhvaryani [mailto:forum@sefindia.org]
Sent: 22 January 2019 16:32
To: general@sefindia.org
Subject: Failure of elevated water tanks supported on shaft staging



Dear Sefians, In the book "Learning from Failures" (1987) by late Er.R.N.Raikar,there are given
some photos of failure of these structures.These shafts get sunk in the ground.A few years back,a similar failure occurred in NOIDA,when one engineer and some other persons were killed.I had then written a paper on this subject,in the journal
Civil Engineering and Construction Review,October 1999.
Why should these failures occur? I discussed this issue with some of my engineer-friends.I am surprised to know that not many engineers are aware of these failures,not to speak of the reasons thereof.Many engineers believe that
these shafts get sunk in the ground because of poor soil.It is not so at all.The failure occurs because of local buckling of thin shaft circular wall.There is a huge load of self-weight of concrete water tank and the load of water contained in the tank.This huge static load becomes dynamic,when the crippling of the shaft wall takes place due to local buckling of the thin circular wall.Then shaft pierces the raft foundation below it and goes down in the ground in the same way as a caisson is pushed down in the ground.
Surprisingly,there is no mention of local buckling of these structures in the Code IS: 11682-1985, and also no mention in text-books by P.Dayaratnam(1992),N.K.Raju(1988) and S.K.Mallick and A.P.Gupta(1996).
Buckling phenomenon,be it global or local,is a tricky affair in compression members and it leads to failure,if not recognised.
I request all sefians to share their experiences and ideas on this subject in the Forum,
with best wishes and regards,
uhvaryani

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Pronoy Roy Chowdhury
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PostPosted: Tue Jan 22, 2019 6:11 pm    Post subject: Failure of shaft support of elevated water tanks Reply with quote

I am very happy that senior Engineers like Varyani Sir has taken keen interest in the matter of failure of shafts. The shaft construction can actually speed up constructions of ESR. But this structure has failed at few locations in Bhuj 2001 during Earthquake, and consultant Engineers and professors of Earthquake Engineering has indicated  in favour of beam-column supported tanks. Now if sufficient thickness can be ensured for shafts then local buckling failure can be avoided and if proper detailing can be maintained then some ductility can also be permitted in the structure. But there is no rational formula for the thickness of shaft wall. The formula of IS 11682 does not have any basis. If shaft is a thin shell it can be checked for buckling using shell code. But as it is under compression from the water tank filled with water is it not a cantilever column. shall the shaft be designed for membrane forces as a shell or shall it be designed for compression and uni-axial bending like a column. The question is very pointed. Most of the books gives adhoc design methods, but many questions remain unanswered. I am to enclose three resent papers of mine in this field kindly go through if possible, I have tried to express a critical study of the structure. It is open to all Respected structural Engineers kindly comment freely on this issue.
Thanks to all.
Pronoy RoyChowdhury



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N. Prabhakar
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PostPosted: Thu Jan 31, 2019 6:36 am    Post subject: Reply with quote

Dear Er. Pronoy Roy Chowdhury,

You have raised lot of queries on water tanks supported on circular shafts.  Having designed myself few such water towers up to 37 m staging, and over 60 nos. chimneys (heights ranging from 30 m to 275 m)  , I could briefly touch on this subject. here under:

1. The water tower shafts have to be designed for vertical loads (water weight + self weight) and bending moment as a cantilever due to wind/seismic forces.  There will be local circumferential bending moments also in shaft due to wind/seismic forces.  The shaft thickness is normally based on the permissible stresses in concrete and reinforcement due to axial load and bending moments.  As compared to chimney design, axial load is more in the case of water towers.  The IS codes for chimney and water towers specify the same permissible stresses.  The equations given in the IS chimney code for calculation of stresses by working stress method  under axial load and bending moment can be conveniently used  for the design of water tower shafts also.   The emperical equation given in the IS codes for minimum thickness of shaft, in both chimney and water, is based on the earlier American chimney code.  But, in the later version of ACI chimney code, the requirements on shell thickness have been modified and the  minimum shell thickness is increased to 8 inches (200 mm).

2. The water tower shafts have invariably an access opening at ground level which has significant effect in the design of smaller diameter shafts.  This opening in the shaft is to be considered both in the structural analysis and in shaft design.  The detailing of reinforcement around openings requires special care with additional horizontal and vertical reinforcement, and diagonal reinforcement at corners to take care of concentration of stresses around the opening.  

3. There is a concern about buckling of shaft in the case of water towers due to heavy axial load from stored water, which is not dealt by IS codes.  On this matter, I suggest to make reference to the book titled 'Formulas for Stress and Strain' by Roark and Young where 'thin cylindrical tubes' is dealt in chapter on 'Columns and other Compression Members', and 'Buckling of Shells'  is dealt in chapter on 'Elastic Stability'.  Formulas given in the Tables of the book for stress calculation are helpful in deciding the shaft thickness to avoid the buckling problem.

4. Minimum vertical  reinforcement of 0.25% of shaft wall area is in order, and this cannot be compared to 0.8% in column area. The vertical and circumferential  reinforcement in shaft are to be provided in two layers near each face to account for drag effect when slip-form method of construction is used and also to resist circumferential wind moment occurring at both faces in large diameter shafts.  The laps in reinforcement should be staggered in groups of three.  The minimum cover to reinforcement is to be 50 mm.

5. There is an unnecessary scare about the collapse of water towers supported on shafts, where least information about the cause of such collapse is given.  There is nothing wrong in this structural system.  The collapse could be due to several reasons, viz. a) poor soil condition, b) under design of shaft foundation, c) 150 mm shell with single layer reinforcement, d) not providing additional reinforcement around access openings at ground level, e) under design of shaft without considering wind load forces, and f) poor quality of construction..

Trust, you will find the above observations useful.  I am attaching herewith two technical papers of mine on water retaining structures which you may find interesting.

With best wishes,

Yours truly,

N. Prabhakar, BE CEng(I) MIStructE (UK) MIE (Ind)
Chartered Structural Engineer
Vasai (E), 401 208



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PostPosted: Thu Jan 31, 2019 12:35 pm    Post subject: Re: Failure of elevated water tanks supported on shaft staging Reply with quote

Jayant Lakhlani wrote:
Dear Mr Varyani

IS : 2210  1988, Cl. 9.3.1 provides a check for buckling stress in cylindrical shells.



Dear Er Lakhlani,

IS: 2210 1988 Cl. 9.3.1 pertains to part-cylindrical shells in bending, as shown in Fig. 1 of the code. For complete cylinder in axial compression, please refer to table 15.2 of Roark's Formulas.

Regards,

A S Oundhakar
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V. S. Kelkar
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PostPosted: Thu Feb 07, 2019 12:30 pm    Post subject: Failure of elevated water tanks supported on shaft staging Reply with quote

In the past I had analysed/designed or proof checked several elevated storage reservoirs consisting of circular cylindrical walls with dome roofs, part slab/part dome roofs or Intze type with conical and domical bottoms and cylindrical wall + dome roof on top. They were supported either on cylindrical shafts or on column-beam space frame structures. I had then developed a software for FE analysis of such Shells of Revolution using a simplified Finite Element which gave good results for design. We used it for analysis and design of several such tanks as well as circular silos etc. The software readily gave meridianal and circumferential (hoop) forces and corresponding BMs at various locations of the tanks – convenient for design. Now, you can also do the analysis of the tanks in Etabs or Staad but the results may not be easy to interpret in terms of design forces and moments.

I had also given reports on failures of tanks(designed by others) - one in Aurangabad, one in Nashik and one near Kolhapur. The first two were supported on cylindrical shafts and the third on beam/columns. Failure was not due to any buckling inadequacy of shafts. Generally, the radius to thickness ratio of such RCC cylindrical shafts is low compared to those of pressure vessels or aircraft/space vehicle fuselages and height is also limited and so buckling may not be a major problem. Interestingly, after failure of the first tank Govt. of Maharashtra decided not to accept tanks supported on shafts. But after that there was failure of the third tank which was on beam/columns. Generally, contracts of such large tanks are given by govt. on lump sum bids based on contractor’s design which they try to do ultra economical while the construction quality is not commensurate with that. Also, full design load is present in tanks unlike in residential/office buildings.

With best regards,

Vasant Kelkar



This e-mail is confidential and is for the use of intended recipient(s) only. If you are not the intended recipient, Please delete it and notify us immediately. Please do not copy, use or distribute this e-mail. While we have taken precautions against the risk of transmitting computer viruses, we cannot accept responsibility for any loss or damage caused by your accessing this e-mail.


From: Jayant Lakhlani [mailto:forum@sefindia.org]
Sent: Tuesday, January 22, 2019 8:24 PM
To: general@sefindia.org
Subject: [SEFI] Re: Failure of elevated water tanks supported on shaft staging



Dear Mr Varyani

IS : 2210 – 1988, Cl. 9.3.1 provides a check for buckling stress in cylindrical shells. You are right that no text book explains complete design of elevated tank, particularly on shaft type staging. It becomes dangerous when an inexperienced engineer designs such type of structures following the text book, without having in depth knowledge about probable failure criteria for that type of structure and codal checks to prevent such failures. We have been designing elevated tanks with shaft type staging, while applying very first check on shaft thickness for buckling. Shaft section with openings / cut outs (for doors, pipes etc) shall become critical for buckling. Many a times shaft thickness is required to be increased to avert buckling, even though all other stresses are within permissible limits.

Regards.

Jayant Lakhlani
For
Lakhlani Associates
--(URL Auto Removed)

From: uhvaryani [mailto:forum@sefindia.org] ([mailto:forum@sefindia.org])
Sent: 22 January 2019 16:32
To: general@sefindia.org (general@sefindia.org)
Subject: Failure of elevated water tanks supported on shaft staging



Dear Sefians, In the book "Learning from Failures" (1987) by late Er.R.N.Raikar,there are given
some photos of failure of these structures.These shafts get sunk in the ground.A few years back,a similar failure occurred in NOIDA,when one engineer and some other persons were killed.I had then written a paper on this subject,in the journal
Civil Engineering and Construction Review,October 1999.
Why should these failures occur? I discussed this issue with some of my engineer-friends.I am surprised to know that not many engineers are aware of these failures,not to speak of the reasons thereof.Many engineers believe that
these shafts get sunk in the ground because of poor soil.It is not so at all.The failure occurs because of local buckling of thin shaft circular wall.There is a huge load of self-weight of concrete water tank and the load of water contained in the tank.This huge static load becomes dynamic,when the crippling of the shaft wall takes place due to local buckling of the thin circular wall.Then shaft pierces the raft foundation below it and goes down in the ground in the same way as a caisson is pushed down in the ground.
Surprisingly,there is no mention of local buckling of these structures in the Code IS: 11682-1985, and also no mention in text-books by P.Dayaratnam(1992),N.K.Raju(1988) and S.K.Mallick and A.P.Gupta(1996).
Buckling phenomenon,be it global or local,is a tricky affair in compression members and it leads to failure,if not recognised.
I request all sefians to share their experiences and ideas on this subject in the Forum,
with best wishes and regards,
uhvaryani

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rajesh modi
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PostPosted: Sat Feb 16, 2019 5:30 am    Post subject: Failure of elevated water tanks supported on shaft staging Reply with quote

Nice information

Sent from RediffmailNG on Android




From: "V. S. Kelkar" <forum@sefindia.org>
Sent: Sat, 16 Feb 2019 10:18:36 GMT+0530
To: general@sefindia.org
Subject: [SEFI] Failure of elevated water tanks supported on shaft staging

           In the past I had analysed/designed or proof checked several elevated storage reservoirs consisting of circular cylindrical walls with dome roofs, part slab/part dome roofs or Intze type with conical and domical bottoms and cylindrical wall + dome roof on top. They were supported either on cylindrical shafts or on column-beam space frame structures. I had then developed a software for FE analysis of such Shells of Revolution using a simplified Finite Element which gave good results for design. We used it for analysis and design of several such tanks as well as circular silos etc. The software readily gave meridianal and circumferential (hoop) forces and corresponding BMs at various locations of the tanks  convenient for design. Now, you can also do the analysis of the tanks in Etabs or Staad but the results may not be easy to interpret in terms of design forces and moments.

I had also given reports on failures of tanks(designed by others) - one in Aurangabad, one in Nashik and one near Kolhapur. The first two were supported on cylindrical shafts and the third on beam/columns. Failure was not due to any buckling inadequacy of shafts. Generally, the radius to thickness ratio of such RCC cylindrical shafts is low compared to those of pressure vessels or aircraft/space vehicle fuselages and height is also limited and so buckling may not be a major problem. Interestingly, after failure of the first tank Govt. of Maharashtra decided not to accept tanks supported on shafts. But after that there was failure of the third tank which was on beam/columns. Generally, contracts of such large tanks are given by govt. on lump sum bids based on contractor’s design which they try to do ultra economical while the construction quality is not commensurate with that. Also, full design load is present in tanks unlike in residential/office buildings.

With best regards,

Vasant Kelkar



This e-mail is confidential and is for the use of intended recipient(s) only. If you are not the intended recipient, Please delete it and notify us immediately. Please do not copy, use or distribute this e-mail. While we have taken precautions against the risk of transmitting computer viruses, we cannot accept responsibility for any loss or damage caused by your accessing this e-mail.


From: Jayant Lakhlani [mailto:forum@sefindia.org]
Sent: Tuesday, January 22, 2019 8:24 PM
To: general@sefindia.org
Subject: [SEFI] Re: Failure of elevated water tanks supported on shaft staging



Dear Mr Varyani

IS : 2210  1988, Cl. 9.3.1 provides a check for buckling stress in cylindrical shells. You are right that no text book explains complete design of elevated tank, particularly on shaft type staging. It becomes dangerous when an inexperienced engineer designs such type of structures following the text book, without having in depth knowledge about probable failure criteria for that type of structure and codal checks to prevent such failures. We have been designing elevated tanks with shaft type staging, while applying very first check on shaft thickness for buckling. Shaft section with openings / cut outs (for doors, pipes etc) shall become critical for buckling. Many a times shaft thickness is required to be increased to avert buckling, even though all other stresses are within permissible limits.

Regards.

Jayant Lakhlani
For
Lakhlani Associates
--(URL Auto Removed)

From: uhvaryani [mailto:forum@sefindia.org] ([mailto:forum@sefindia.org])
Sent: 22 January 2019 16:32
To: general@sefindia.org (general@sefindia.org)
Subject: Failure of elevated water tanks supported on shaft staging



Dear Sefians, In the book "Learning from Failures" (1987) by late Er.R.N.Raikar,there are given
some photos of failure of these structures.These shafts get sunk in the ground.A few years back,a similar failure occurred in NOIDA,when one engineer and some other persons were killed.I had then written a paper on this subject,in the journal
Civil Engineering and Construction Review,October 1999.
Why should these failures occur? I discussed this issue with some of my engineer-friends.I am surprised to know that not many engineers are aware of these failures,not to speak of the reasons thereof.Many engineers believe that
these shafts get sunk in the ground because of poor soil.It is not so at all.The failure occurs because of local buckling of thin shaft circular wall.There is a huge load of self-weight of concrete water tank and the load of water contained in the tank.This huge static load becomes dynamic,when the crippling of the shaft wall takes place due to local buckling of the thin circular wall.Then shaft pierces the raft foundation below it and goes down in the ground in the same way as a caisson is pushed down in the ground.
Surprisingly,there is no mention of local buckling of these structures in the Code IS: 11682-1985, and also no mention in text-books by P.Dayaratnam(1992),N.K.Raju(1988) and S.K.Mallick and A.P.Gupta(1996).
Buckling phenomenon,be it global or local,is a tricky affair in compression members and it leads to failure,if not recognised.
I request all sefians to share their experiences and ideas on this subject in the Forum,
with best wishes and regards,
uhvaryani
     



     
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ajay2612
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PostPosted: Sat Feb 16, 2019 5:30 am    Post subject: Failure of elevated water tanks supported on shaft staging Reply with quote

thnks sir

From: "V. S. Kelkar" <forum@sefindia.org>
Sent: Sat, 16 Feb 2019 10:18:10
To: general@sefindia.org
Subject: [SEFI] Failure of elevated water tanks supported on shaft staging
           In the past I had analysed/designed or proof checked several elevated storage reservoirs consisting of circular cylindrical walls with dome roofs, part slab/part dome roofs or Intze type with conical and domical bottoms and cylindrical wall + dome roof on top. They were supported either on cylindrical shafts or on column-beam space frame structures. I had then developed a software for FE analysis of such Shells of Revolution using a simplified Finite Element which gave good results for design. We used it for analysis and design of several such tanks as well as circular silos etc. The software readily gave meridianal and circumferential (hoop) forces and corresponding BMs at various locations of the tanks  convenient for design. Now, you can also do the analysis of the tanks in Etabs or Staad but the results may not be easy to interpret in terms of design forces and moments.

I had also given reports on failures of tanks(designed by others) - one in Aurangabad, one in Nashik and one near Kolhapur. The first two were supported on cylindrical shafts and the third on beam/columns. Failure was not due to any buckling inadequacy of shafts. Generally, the radius to thickness ratio of such RCC cylindrical shafts is low compared to those of pressure vessels or aircraft/space vehicle fuselages and height is also limited and so buckling may not be a major problem. Interestingly, after failure of the first tank Govt. of Maharashtra decided not to accept tanks supported on shafts. But after that there was failure of the third tank which was on beam/columns. Generally, contracts of such large tanks are given by govt. on lump sum bids based on contractor’s design which they try to do ultra economical while the construction quality is not commensurate with that. Also, full design load is present in tanks unlike in residential/office buildings.

With best regards,

Vasant Kelkar



This e-mail is confidential and is for the use of intended recipient(s) only. If you are not the intended recipient, Please delete it and notify us immediately. Please do not copy, use or distribute this e-mail. While we have taken precautions against the risk of transmitting computer viruses, we cannot accept responsibility for any loss or damage caused by your accessing this e-mail.


From: Jayant Lakhlani [mailto:forum@sefindia.org]
Sent: Tuesday, January 22, 2019 8:24 PM
To: general@sefindia.org
Subject: [SEFI] Re: Failure of elevated water tanks supported on shaft staging



Dear Mr Varyani

IS : 2210  1988, Cl. 9.3.1 provides a check for buckling stress in cylindrical shells. You are right that no text book explains complete design of elevated tank, particularly on shaft type staging. It becomes dangerous when an inexperienced engineer designs such type of structures following the text book, without having in depth knowledge about probable failure criteria for that type of structure and codal checks to prevent such failures. We have been designing elevated tanks with shaft type staging, while applying very first check on shaft thickness for buckling. Shaft section with openings / cut outs (for doors, pipes etc) shall become critical for buckling. Many a times shaft thickness is required to be increased to avert buckling, even though all other stresses are within permissible limits.

Regards.

Jayant Lakhlani
For
Lakhlani Associates
--(URL Auto Removed)

From: uhvaryani [mailto:forum@sefindia.org] ([mailto:forum@sefindia.org])
Sent: 22 January 2019 16:32
To: general@sefindia.org (general@sefindia.org)
Subject: Failure of elevated water tanks supported on shaft staging



Dear Sefians, In the book "Learning from Failures" (1987) by late Er.R.N.Raikar,there are given
some photos of failure of these structures.These shafts get sunk in the ground.A few years back,a similar failure occurred in NOIDA,when one engineer and some other persons were killed.I had then written a paper on this subject,in the journal
Civil Engineering and Construction Review,October 1999.
Why should these failures occur? I discussed this issue with some of my engineer-friends.I am surprised to know that not many engineers are aware of these failures,not to speak of the reasons thereof.Many engineers believe that
these shafts get sunk in the ground because of poor soil.It is not so at all.The failure occurs because of local buckling of thin shaft circular wall.There is a huge load of self-weight of concrete water tank and the load of water contained in the tank.This huge static load becomes dynamic,when the crippling of the shaft wall takes place due to local buckling of the thin circular wall.Then shaft pierces the raft foundation below it and goes down in the ground in the same way as a caisson is pushed down in the ground.
Surprisingly,there is no mention of local buckling of these structures in the Code IS: 11682-1985, and also no mention in text-books by P.Dayaratnam(1992),N.K.Raju(1988) and S.K.Mallick and A.P.Gupta(1996).
Buckling phenomenon,be it global or local,is a tricky affair in compression members and it leads to failure,if not recognised.
I request all sefians to share their experiences and ideas on this subject in the Forum,
with best wishes and regards,
uhvaryani
     



     
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NanthakumarGanesan
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PostPosted: Fri May 10, 2019 3:30 am    Post subject: Failure of elevated water tanks supported on shaft staging Reply with quote

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