Pavement Subgrade Problem
Pavement Subgrade Problem
(OP)
I need to remove some old fill and replace it under a road adjacent to an abutment for a one lane bridge. I want to start at the abutment and excavate in 4 foot-long sections so that if an emergency vehicle needs to use the road, it could be filled "rapidly" and some 4'x8' steel plates could be placed on top to let the vehicle pass.
Could I use rip-rap (specs?) for emergency fill and then use a mixture of rip-rap, crushed stone (specs?) and flowable fill (2500 psi) for my permanent fill? I plan to excavate 3' deep (minimum) to as much as 5'. Once the flowable fill cured for (?) days, another 4' long section would be opened up. I will need to do this for about 12'-16' on each side of the bridge.
I am planning to use concrete pavement on top. The pavement is asphalt now.
Could I use rip-rap (specs?) for emergency fill and then use a mixture of rip-rap, crushed stone (specs?) and flowable fill (2500 psi) for my permanent fill? I plan to excavate 3' deep (minimum) to as much as 5'. Once the flowable fill cured for (?) days, another 4' long section would be opened up. I will need to do this for about 12'-16' on each side of the bridge.
I am planning to use concrete pavement on top. The pavement is asphalt now.





RE: Pavement Subgrade Problem
RE: Pavement Subgrade Problem
RE: Pavement Subgrade Problem
I only bring these up since apparently the aspect of full time passage of emergency vehicles seems to control what to do. These treatments would likely allow that. I suspect your sequences of trenches may turn out not to work if the trench sides cave in due to weak soil. Would you trench brace every excavation step? Maybe blow the budget.
Question: When you do your rigid pavement job with concrete, how does the fire truck traverse the wet or undercured concrete?
RE: Pavement Subgrade Problem