SU800281A1 - Unit for investigating soil properties - Google Patents

Description

I

The invention relates to the construction and can be used in the study of the physicomechanical and electrical properties of the soil in the field.

A device is known for measuring the electrical properties of soils by the method of electrical logging, which contains a probe with electrodes, current-carrying wires, means of isolation, a device for pressing electrodes against the walls f of the borehole 1.

To measure this device, it is necessary to lower the pre-prepared well, the well, which complicates the study. In addition, it is very difficult to achieve complete contact of the electrodes with the ground, which affects the quality of the research results.

Closest to the present invention is a device for dynamic sounding and at the same time for measuring the electrical properties of the soil, including a cone tip with stationary electrodes installed in it flush with the surface of the cone, rod, device for driving the tip 12.

However, the use of this setup by D.LIA to determine the electrical characteristics of the soil is difficult due to the fact that it is very difficult to ensure reliable contact with the ground of stationary electrodes mounted flush in the conical tip. During the test, the experiment has to be repeated many times to achieve measurement accuracy.

The purpose of the invention is to improve the accuracy of measurements and reduce their time by improving the contact between the electrode and the ground. 5 This goal is achieved by the fact that in an installation that includes a hollow conical tip with electrodes, rods, a device for driving the tip and a device to determine its depth division. dive

The electrodes are mounted with the possibility of extension relative to the tip and are equipped with a displacement means made in the form of a wedge placed 5 in the hollow tip and kinematically connected with the rods.

Claims (2)

The device allows for the study of soil properties without drilling wells, and retractable electrodes provide reliable contact with the soil, which allows for improved measurement accuracy. FIG. Figure 1 shows schematically a conical tip unit for studying the properties of the soil; the section in FIG. 2-i; Section A-A in FIG. 1; The tapered tip includes a hollow body 1 with insulating sleeves 2; adapter 3 connected to the rods 4; detachable 5 and locking 6 rings; a wedge 7 made of a dielectric with conductive guides 8 in which electrodes 9 are mounted with the possibility of free movement; screw pair 10 connecting the tail section of the wedge 7 with adapter 3 through the drill holes, into which the cable 11 is brought out. The installation works as follows. The conical tip is immersed to the required depth in the soil under study and with the help of the rod 4 through the screw pair 10 the wedge 7 is moved downward Electrodes 9, the slides in the guides 8 and the sleeves 2 of the body are pulled out of the cone and crushed into the ground. After the electrodes 9 are advanced, the electrical properties of the soil are measured. The return of the electrodes 9 to the initial position is carried out by the reverse rotation of the rods 4, which causes the wedge 7. to move upwards. The obtained data on the mechanical and electrical characteristics of the soil under study is interpreted on the basis of a previously performed calibration on specific soils. The proposed installation can be widely used in engineering and geological surveys, as well as to control the degree of compaction and moisture in the construction of the road bed, dams, dams, etc. The use of the installation allows us to significantly improve the quality of the data obtained in the study and reduce the time needed to conduct research. The economic effect is 5-10 thousand rubles. in year. The claims of the Inventory — for investigating soil properties, including a hollow conical tip with electrodes, rods, a device for driving a tip, and a device for determining the depth of its immersion, characterized in that, in order to improve the accuracy of measurements by improving the contact between the electrode and the ground, The electrodes are mounted with respect to the tip and are provided with means for moving the wedge placed in a hollow tip and kinematically connected with rods. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 494714, cl. G 01 N 3/18, 1968. 2. Methodical recommendations on the geophysical survey of our railways. M., ZNIIS, 1975.