bridge that is built for a general need, we must check at all times to find obstacles that exist on the bridge so that we can handle it quickly and precisely for the future, because the survey is very necessary as a check for the future.
go into the soil laboratory to test the strength of the soil that is able to win or be able to withstand a large amount of soil depending on the strength of the soil, to determine the strength of the soil it is therefore necessary to conduct the sondir test