Control dry density with compaction coefficient, maximum dry density and water content

Control dry density with compaction coefficient, maximum dry density and water content

Dry density = maximum dry density * compaction coefficient, soil density = dry density * (1 + moisture content)

It is known that the thickness of C20 concrete ground is 10cm and the compaction coefficient of backfill is 0.91

The bearing capacity of backfill soil is determined by static load test, not by calculation. If the compaction coefficient is known, it can only be estimated
1. According to your description, the 10 cm thick C20 concrete should be unreinforced. The improvement of the bearing capacity of the backfill soil by this layer of concrete is not great (it is not big compared with the bearing capacity of the normal foundation soil)
2. It is not enough to know the compaction coefficient of backfill, what soil is used and how deep the backfill is. Most of the backfill in general projects are miscellaneous fill
The known conditions you provided are not enough. You can only roughly estimate the bearing capacity FA = 120kPa (a little conservative)

In the ring cutter sampling, the formula for calculating the actual moisture content, the formula for calculating the actual wet density, the formula for calculating the actual dry density, and the formula for calculating the compaction coefficient?

Calculation formula of actual moisture content: weigh the wet soil, record the data, and then dry the soil sample, record the data. Wet soil mass - dry soil mass = water mass, water mass / dry soil mass * 100% = moisture content. Calculation formula of actual wet density: ring knife and total soil mass - ring knife mass = wet soil mass in ring knife, wet soil mass / ring knife volume = wet soil density

-560 tons of cement is transported from a construction site, which is four times the weight of stones. How many tons of cement and stones are transported?

Cement: 560 tons
Stone: 560 * 1 / 4 = 140 tons
Cement and stone: 560 + 140 = 700 tons