By production of construction works it is necessary to consider density of the soil lying in the construction basis. Admissible indicators of density are specified in the project documentation and depend on a type of soil. Characteristics of a covering should be considered also when choosing the suitable tool by means of which various earth constructions are built. Methods of assessment of density are divided on simplicity and reliability.
It is required to you
- - the cutting ring;
- - knife;
- - hammer;
- - scales;
- - drying cabinet;
- - shovel;
- - measured vessel;
- - drummer densitometer.
Instruction
1. For the majority of soil, except blurring and loose, use the easiest way of determination of density – a method of the cutting ring.
2. In the venue of test clear away the Earth's surface on several centimeters. Establish the cutting ring of 50 cm3. A hand or percussion of a hammer press a ring into soil.
3. By means of a knife cut out a ring about soil breakdown. Smooth out soil level with the lower and top cuts of the cutting ring.
4. Make weighing of mass of damp soil. After that dry test in a drying cabinet and determine by weighing the mass of dry soil.
5. For determination of density of soil use formulas: Rv = (P1 – P2) / V; Rskh = Rv / (1 + 0.01 * W); gderv – the natural density of soil, g/cm3; Rskh – density of dry soil, g/cm3; P1 is the mass of soil before drying together with a ring; P2 is the mass of a ring; V – the internal volume of the cutting ring, cm3; W – humidity of soil, %.
6. For soil with the increased flowability or having stony inclusions use a so-called method of shurfik. It is applied in all cases when the cutting ring it is not possible to remove test.
7. In the place of determination of density of soil dig small shurfik (a vertical trial excavation). Collect the chosen soil in a container and weigh.
8. Over shurfiky establish a tin cone with a measured vessel. Now fill up shurfik and a cone with dry sand and determine the volume of a shurfik. For calculation of density of soil use the formulas given above. A lack of a way – low accuracy.
9. When using a method of a penetration carry out clogging in soil of a special core (stamp) by means of a mechanical hammer. At the same time consider number of the blows necessary for deepening of a core on depth of 10 cm. Determine density of soil by the special table reflecting dependence between the number of the blows spent for immersions of a stamp and soil characteristics.