eswar12
Structural
- Mar 19, 2009
- 7
Need Help in Designing a tower crane foundation on top of steel H-Pile system: (If some one case suggest a step by step procedure would be great) I'm very occasionally used to designing tower crane foundations resting on compacted earth with known bearing capacity. It is pretty straight forward as the checks are bearing,the overturning with the moment in the diagonal direction, punching shear. However, I need help in determining the foundation size taking into consideration a group of steel H-piles and the approach. Any worked example is greatly appreciated.
Loads from the Crane are as follows: (US Units)
-------------------Overturning Moment----------Horizontal Load-----Vertical Load-----Slewing Torque
Out of Operation--------3932----------------------32-------------------278
In Operation------------5145----------------------10-------------------314---------------587
From the Geotech Report
Bearing 3000PSF
Steel H Piles
----------------------Axial Capacity (Kips)---Uplift (kips)-----Lateral Kips(average based on 24 piles group carrying 282 Kips)
HP 12x53----------------270---------------------80----------------12
HP 14x73----------------370---------------------90----------------12
Output/Trying to calculate
1. Base Size and Working Pile Load (How to calculate)
(Trying to keep the base size to 17' X 17')
2. How to determine the overturning moment vs the resisting moment
3. Distribute the horizontal and the slewing torgue as a lateral load into each steel pile vs lateral capacity of the pile
4. Determine the no. of piles required and the connection of the H-Pile to the Pile cap
Based on the above information and doing some preliminary calculations, it seems the horizontal shear and the slewing torque on the steel H-Pile seems to be the weakest link requiring a decent number of piles.
All inputs are greatly appreciated.
Thanks for your help.
Loads from the Crane are as follows: (US Units)
-------------------Overturning Moment----------Horizontal Load-----Vertical Load-----Slewing Torque
Out of Operation--------3932----------------------32-------------------278
In Operation------------5145----------------------10-------------------314---------------587
From the Geotech Report
Bearing 3000PSF
Steel H Piles
----------------------Axial Capacity (Kips)---Uplift (kips)-----Lateral Kips(average based on 24 piles group carrying 282 Kips)
HP 12x53----------------270---------------------80----------------12
HP 14x73----------------370---------------------90----------------12
Output/Trying to calculate
1. Base Size and Working Pile Load (How to calculate)
(Trying to keep the base size to 17' X 17')
2. How to determine the overturning moment vs the resisting moment
3. Distribute the horizontal and the slewing torgue as a lateral load into each steel pile vs lateral capacity of the pile
4. Determine the no. of piles required and the connection of the H-Pile to the Pile cap
Based on the above information and doing some preliminary calculations, it seems the horizontal shear and the slewing torque on the steel H-Pile seems to be the weakest link requiring a decent number of piles.
All inputs are greatly appreciated.
Thanks for your help.