SU1675485A1 - Device for determining strength and deformation characteristics of soil - Google Patents

Abstract

The invention relates to devices for determining the strength and deformation characteristics of soils during engineering surveys in construction. The aim of the invention is to expand the range of measured parameters of the soil and reduce the complexity of the test. A device for determining the strength and deformation characteristics of soils includes two coaxially placed one above the other punching dies, the lower one of which is rigidly connected to the outer hollow bar having longitudinal grooves in its lower part, and the upper one through brackets missed in the longitudinal grooves of the outer bar internal hollow barbell. The load device is made in the form of a power screw of variable cross-section with stops, which interacts by means of a threaded connection with the flange of the outer hollow rod and by means of stops with the flange of the internal hollow rod. Measuring devices in the form of torque washers are installed on the power screw between the lugs and the flange of the inner hollow rod. Outside the floor, the rod is equipped with a casing pipe and a cargo platform installed on its upper part. 2 Il. ate with

Description

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The invention relates to devices for determining the strength and deformation characteristics of soils during engineering surveys in construction.

The aim of the invention is to expand the range of measured soil parameters and reduce the complexity of the test. niy

FIG. 1 shows the device in section; in fig. 2 shows section A-A in FIG. one.

The device includes two coaxially located one above the other vintolopastnyh stamp, the lower stamp 1 is rigidly connected with the outer hollow rod 2, having longitudinal grooves 3 in its lower part, and the upper stamp 4 by means of brackets 5, missed in the longitudinal grooves 3 of the outer rod, connected to the inner hollow barbell 6.

The load devices are made in the form of a power screw 7 of variable cross-section with supporting washers 8 and counter-nuts 9, interacting by means of a threaded connection with the flange 10 of the loading bar and by means of the supporting ibs 8 with the flange 11 of the internal rod, and also the loading platform 12. mounted on the external rod.

The measuring devices are made in the form of torque washers 13 installed on the power screw 7 between the support washers 8 and the flange 11 of the inner rod, and the deformeter 14 installed to measure the relative movement of the rods.

An extension of the rods is provided for testing the depth of the soil mass. A casing 15 is supplied with the device. To ensure mutual fixation, coaxially arranged radial holes 16 are made in the rods.

The device works as follows.

Before immersion in the soil under study, the necessary clearance between screw-and-dies dies 1 and 4 is established with the help of the power screw 7. With the help of a rotator (not shown) by screwing the device into the soil under study. At a given mark, the power screw 7 is turned to the upper position by turning it counterclockwise until the moment of the lower torque wrench 13 interacts with the flange 11 of the inner rod. Hinge loading platform 12 and deformometer 14 remove the zero base count.

To determine the stamp module, the deformation loads the load platform 12 with a calibrated load. The load force is transmitted to the stamp 1. At each stage of the load, the soil sludge under the stamp is measured using a deformator 14. The die modulus of elasticity is determined from the measurement results1.

To determine the limiting resistance of the soil right away, do not remove the tared cargo from the cargo platform, rotating the power screw 7 clockwise loads the upper die 4 until the ground is cut off along the fixed vertical platform between the upper die 4 and the gap above the lower die 1 formed determining die strain modulus. The shear force is fixed by the upper torque wrench 13. According to the measurement results, the limiting resistance of the soil to shear is determined.

After that, the loading platform 12 is unloaded and by screwing in, the dies 1 and 4 are moved to the zone of undisturbed soil by previous tests (2-3 turns below).

To determine the deformation compression modulus with limited lateral expansion of the ground, the power screw 7 is tightened clockwise.

5 At the same time, the screw-stamping dies 1 and 4 mutually approach each other, compressing the soil between them. The compression force is fixed by the upper torque wrench 13, and the soil deformation at the load step is fixed by the strain gauge 14.

Claims (1)

Claims The device, prior to determining the strength and deformation characteristics of soils, includes two coaxially located wintry pins one above the other, outer and inner hollow rods with flanges at the free upper ends, and loading and measuring methods, which are different in that parameters of the soil and reducing the complexity of testing, the device is equipped with a cargo platform and casing, 5, the outer floor of the rod is made with longitudinal slots in its lower part, rigidly connected to the lower vnutololastny stamp and installed in the casing pipe, the inner floor of the rod is rigidly connected 0 with an upper screw-stamp by means of brackets missed in the longitudinal grooves of the outer hollow rod with the possibility of axial movement, the load device is made in the variable desil screw of cross-section with stops that cooperate by means of a threaded connection with the flange of the outer hollow rod and by means of the stops with the flange of the inner hollow rod , while the cargo platform is fixed in the upper part of the outer hollow rod, and the measuring devices are made in the form of torque washers usta5 Credited force on the screw between the abutments and the flange of the inner hollow rod. Hi 13 1