adk48ist
Structural
- Apr 23, 2002
- 10
I have a unique situation looking for assistance.
A precast concrete tank ( 10'x17' footprint and 9' high) is to be installed in ground, with 2' soil cover. Water TAble is at grade; calculation showed that buoyancy forces govern; hence the tank will lift up unles more weight is added. The contractor decides to add a 12"x12" extension slab around the periphery of the tank at the bottom.This additional slab(shelf) will be poured at site after the tank is inground. This method is required because of the transportation and handling of the tank segments.
To accomplish this Speed Dowels are used in the tank at the bottom of walls every 24". Before the concrete is poured at site for creating the extension slab Dowels ( i.e. #6 deformed bars of certain lenght is installed in the openings at the bottom of the walls. The question is how to make sure that these dowels will not pull out or break. I did calculation for required development length ( hence bond stress). But I am not sure that this is sufficient. Do I have also check concrete pullout considering edge distance , concrete cover etc. Appreciate your guidance in this issue. Thanks
A precast concrete tank ( 10'x17' footprint and 9' high) is to be installed in ground, with 2' soil cover. Water TAble is at grade; calculation showed that buoyancy forces govern; hence the tank will lift up unles more weight is added. The contractor decides to add a 12"x12" extension slab around the periphery of the tank at the bottom.This additional slab(shelf) will be poured at site after the tank is inground. This method is required because of the transportation and handling of the tank segments.
To accomplish this Speed Dowels are used in the tank at the bottom of walls every 24". Before the concrete is poured at site for creating the extension slab Dowels ( i.e. #6 deformed bars of certain lenght is installed in the openings at the bottom of the walls. The question is how to make sure that these dowels will not pull out or break. I did calculation for required development length ( hence bond stress). But I am not sure that this is sufficient. Do I have also check concrete pullout considering edge distance , concrete cover etc. Appreciate your guidance in this issue. Thanks
