Miningman (sorry don't know how to mention anyone yet in these threads) the tunnel is for heavy traffic. Roughly 30m wide by 1km long. Over the blinding we'll have waterproofing then the tunnel foundation / base which is 1.7m thick and then 4 walls above the base which carry a roof that's also...
The specifications we follow are stringent. I cannot change the 30MPa requirement nor the minimum thickness of 10cm. As hokie66 stated above this blinding surface will be used for both purposes: providing a hard and level surface for the rebar and also as a substrate for the waterproofing.
The...
Hello fellow Engineers!
I am in the process of building a large tunnel and the existing earth is extremely tough rock. We are using rock breakers to reach the required level (bottom of blinding) but I am facing a problem with accurate leveling. Rock breakers cannot be pinpoint in reaching the...