GB1497872A - Testing of soils - Google Patents

Abstract

1497872 Soil testing CEMENTATION GROUND ENG Ltd 30 Jan 1976 [16 Jan 1975] 2004/75 Heading G1S [Also in Divisions E2 and F2] A method of testing soil or other similar material at various levels in the soil or other material which comprises the steps of: 1. placing an assembly of a casing, a penetrating member and a drive rod at a' first level at which it is desired to test the soil or other material, the assembly being such that the drive rod is operatively connected to the penetrating member and extends longitudinally through the casing; 2. subjecting the penetrating member via the drive rod to repeated blows urging the penetrating member into the soil or other material while the casing is stationary and observing the penetration in relation to the number of blows applied; 3. driving the casing into the soil or other material until the end of the casing contacts the penetrating member and the penetrating member is at a second level at which it is desired to test the soil; and 4. repeating step (2). In soil testing apparatus for carrying out the above method a cone 2 Fig. 1(1) having a sleeve 3 is first pushed into the ground by driving a casing 5 downwardly using a static or dynamic load. A cap 8, Fig. 1(2) is then placed over a drive rod 4 connected directly to the cone 2 and is driven downwardly by a weight 9 until the cone alone penetrates further into the ground Fig. 1(3). In one test the number of blows from the weight required to drive the cone into the ground is recorded for every three inches up to a maximum of eighteen inches. The cap 8 is then removed and further lengths of drive rod 4 and casing 5 are added. A weight 10 attached to the outside of the casing, Fig. 2, may then be raised upwardly along the casing and dropped on to an anvil 12 mounted .on a clamp 11 fixed to the casing, in this way the further casing is driven into the soil. When it is desired to remove the casing from the ground, hooks 13 are engaged so that the means for raising the weight 10 can be used to draw the casing 5 from the ground. In Fig. 3 the lower end of cap 8 itself strikes the anvil. In Fig. 4, a special coupling member 19 (see also Divisions E2 and F2) is used to connect the cap 8 and casing 5 and the weight acts directly on the cap. In Fig. 9 a permeability cell 38 is provided at 39, water being supplied to the soil through holes 40 in the casing through conduits 41 and splined grooves 42 in the casing. The cell is exposed to the coil when the cone 2, 3 is driven into the ground beyond the casing. In another construction the cell comprises a plurality of grooved washers in a stack, the grooves providing passages from the interior to the exterior of the assembly so that water may be passed through the cell and into the surrounding soil, the water pressure and rate of flow being observed.