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Bharathhassan SEFI Member
Joined: 17 Nov 2008 Posts: 15
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Posted: Thu Aug 29, 2013 3:39 pm Post subject: How to design Hoardings / advertisment boards |
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Hi Friends / Respected Senoirs
Please help me to design hoardings itsabout 40' x60' at a height of 12' from terrace of 4 story building .<o></o>
I have to support on the six columns .The structural arrangments attached below .<o></o>
The members are failings in slenderness .
staad model is also attached .
kindly guide me to design hoading using angles are channels ,cant use heavier members .
<o></o> |
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pravin_shirsath ...
Joined: 23 Jan 2011 Posts: 66
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Posted: Fri Aug 30, 2013 6:11 am Post subject: |
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Use built up sections of angles with bracing .
Define section in prismatic property.
Hoarding design is well explained in SP-64 |
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es_jayakumar General Sponsor
Joined: 24 Nov 2011 Posts: 1408 Location: Cochin
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Posted: Sun Jun 29, 2014 1:38 pm Post subject: |
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Dear SEFIans,
The details of the proposed steel frame work of a 7.50mx3.00m size hoarding board and its foundation is attached. Please peruse and suggest modifications if any. Foundation proposed is a combined footing for a pair of front and back leg, in order to offer more counter weight (including that from backfill soil) and hence stability, for wind induced toppling forces.
Regards,
E S Jayakumar |
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balki16 ...
Joined: 04 Nov 2012 Posts: 111
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Posted: Mon Jun 30, 2014 1:02 am Post subject: |
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Dear Sir
In hoardings more importance should be given for the stability . They are light structures and tend get blown away due to heavy wind.
There has to be adequate dead weight at the foundations.
The members should be properly braced.
Regards
K. B. |
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es_jayakumar General Sponsor
Joined: 24 Nov 2011 Posts: 1408 Location: Cochin
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Posted: Mon Jun 30, 2014 5:49 am Post subject: |
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Dear SEFIans,
The details of the proposed steel frame work of a 7.50mx3.00m size hoarding board and its foundation is attached. Please peruse and suggest modifications if any. Foundation proposed is a combined footing for a pair of front and back leg, in order to offer more counter weight (including that from backfill soil) and hence stability, for wind induced toppling forces.
Regards,
E S Jayakumar |
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es_jayakumar General Sponsor
Joined: 24 Nov 2011 Posts: 1408 Location: Cochin
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Posted: Fri Jul 18, 2014 1:44 pm Post subject: |
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Dear Sefians,
A girder, say ISMB 150, is proposed to be embedded in the parapet wall at terrace of a building, which acts as the support of a roof top hoarding structure. This girder transmits 3 MT tension to the parapet wall due to wind load at 50cm depth from the top of the parapet wall, 230mm thick. Will the 50cm height wall above the girder be safe to sustain the tension, by arch action or so ? The girder end will be embedded using concrete filled in openings cut out in the wall. Will the system require re-bar anchoring to the beam beneath the parapet wall ?
Regards,
E S Jayakumar |
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balki16 ...
Joined: 04 Nov 2012 Posts: 111
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Posted: Sat Jul 19, 2014 1:33 am Post subject: |
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Dear sir
50 Cm embedment in a brick wall of 230 MM thick will not be sufficient to resist 3000 kg of tension.
It is presumed that 3 tonne tension is net after accounting the dead weight of the structure.
the dead weight of the support has to be at least 3000x1.1 Kg.
It means you have to have concrete of about 1.5 Cum in which the steel section has to be embedded with proper base plate.
Alternatively you can anchor the steel section to the roof slab using suitable expansion anchors like HILTI
Regards
K. B. |
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N. Prabhakar General Sponsor
Joined: 25 Apr 2009 Posts: 474
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Posted: Sat Jul 19, 2014 7:07 am Post subject: |
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Dear Bharathhassan,
I note that are designing a large size hoarding which is to be mounted on the top of an existing 4 storey building.
I am completely against putting up any hoarding on the top of an existing building as the roof of buildings are not normally designed for forces acting on it from hoarding supports due to self weight and wind loads. While fixing the hoarding supports to brick parapet walls or concrete roof slab, the existing water-proof layer on the roof will be greatly disturbed causing severe leakage in the top most storey of the building. Repairing of an existing water-proof layer is not easy and never satisfactory. I have known of many cases of this leakage problem where hoardings have been mounted on the roof.
Considering the above, we as Structural Engineers should advise them not to put up a hoarding on the top of a roof. This is our obligation to the society.
I trust you will consider my views in right prospective.
With best wishes,
N. Prabhakar
Chartered Structural Engineer
Vasai (E) |
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N. Prabhakar General Sponsor
Joined: 25 Apr 2009 Posts: 474
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Posted: Sat Jul 19, 2014 7:08 am Post subject: |
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Dear Bharathhassan,
I note that are designing a large size hoarding which is to be mounted on the top of an existing 4 storey building.
I am completely against putting up any hoarding on the top of an existing building as the roof of buildings are not normally designed for forces acting on it from hoarding supports due to self weight and wind loads. While fixing the hoarding supports to brick parapet walls or concrete roof slab, the existing water-proof layer on the roof will be greatly disturbed causing severe leakage in the top most storey of the building. Repairing of an existing water-proof layer is not easy and never satisfactory. I have known of many cases of this leakage problem where hoardings have been mounted on the roof.
Considering the above, we as Structural Engineers should advise them not to put up a hoarding on the top of a roof. This is our obligation to the society.
I trust you will consider my views in right prospective.
With best wishes,
N. Prabhakar
Chartered Structural Engineer
Vasai (E) |
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es_jayakumar General Sponsor
Joined: 24 Nov 2011 Posts: 1408 Location: Cochin
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Posted: Sun Jul 20, 2014 2:04 am Post subject: |
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Dear Sirs,
The sketch of the proposed roof top hoarding structure is enclosed. The arrangement completely eliminates the struts supporting on the slab, which may be unsafe. They are supported on an ISMC girder, which, in turn, is embedded its either ends in the parapet wall, in a concrete block, which has rebars anchored to the beam below inside it, to take care tension. The approximate maximum compression force and tension force at the end of the girder are 4 MT and 3 MT respectively. Please point out the drawbacks of the arrangement, if any. The span of the hoarding is 6.50m, the total height of the staging (including the board) is 5.00m and the height of the board is 3.00m.
Regards,
E S Jayakumar |
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