Minimum embedment of Pedestal Support
Minimum embedment of Pedestal Support
(OP)
Can anybody share any ideas as to what is the minimum embedment of a pedestal support.
We have fabricated a pre-cast concrete 300mm x 300mm x 600mm depth designed to support a 50kg instrument junction box. i did a calculation to determine the required embedment to the ground considering the lateral resistance of soil and is constrained on top with asphalt pavement.i used a calculation guide from IBC and it only requires 450mm embedment.
However,the site inspector insisted to use 600mm embedment based on their similar project. in this case we are 150mm less than his requirements. What will be the most suitable solution to our case?
Thank you.
We have fabricated a pre-cast concrete 300mm x 300mm x 600mm depth designed to support a 50kg instrument junction box. i did a calculation to determine the required embedment to the ground considering the lateral resistance of soil and is constrained on top with asphalt pavement.i used a calculation guide from IBC and it only requires 450mm embedment.
However,the site inspector insisted to use 600mm embedment based on their similar project. in this case we are 150mm less than his requirements. What will be the most suitable solution to our case?
Thank you.






RE: Minimum embedment of Pedestal Support
RE: Minimum embedment of Pedestal Support
RE: Minimum embedment of Pedestal Support
And is the extra 6 inches worth even arguing about? Even paying retail, the added concrete costs just $2, and either of us could have dug the extra 6 inches for a couple of dozen holes in the time this conversation took.
RE: Minimum embedment of Pedestal Support
Cost for the additional 6" may not be an issue, but the issue is, how can we add this 6" to our precast pedestals? We already fabricated about 300 pcs, 300mm x 300mm x 600mm (450mm embedment and 150mm above the ground). These are intended not just for the junction boxes but also for cable tray supports along the entire cable route. Cable tray supports will not give the critical support requirement since it is close to the ground and supports were spaced close enough.
Can we just add the 150mm at the bottom and provide anchorage to our pre-cast? Or how can i convince the inspector that 150mm is not worth arguing in terms of structural stability by presenting the facts through calculation?
RE: Minimum embedment of Pedestal Support
As low as the forces are, adding an additional length of concrete would probably suffice, but obviously doing this to 300 pieces would not be trivial. If you have the ability to drop fresh concrete into each hole before placing the precast pedestal, you would probably get satisfactory results, particularly as low as the stresses would be. One possibility would be to place a block in the bottom of each hole and adhere it to the precast with mortar or other adhesive.
RE: Minimum embedment of Pedestal Support
RE: Minimum embedment of Pedestal Support