Expansive soil three-way water swelling rate and swelling force tester

Abstract

The invention relates to a tester for three-way water-absorbing swelling rate and expansion force of expansive soil. The instrument includes a sample placing device and a test device for expansion rate and expansion force. The sample placement device includes a horizontal baffle and a water collection base, and the sample is placed on the water collection base. Expansion rate and expansion force test device includes deformation test device and water injection device, deformation test device includes pressure plate, pressure transmission frame, horizontal guide rail, pulley, dial indicator, measuring ring, hook, weight, stacking plate and base ; The water injection device includes a water storage container, a support frame, a water delivery pipe, a valve, and a drip plate. The sample is placed on the water collecting base, and the weight is added to the stacking plate to make the sample generate a certain pressure, and then the water injection valve is opened, and the water in the water storage container enters the sample through the drip plate, so that the sample has an expansion rate. and expansion force. The invention can effectively test the expansion rate and expansion force of the expansive soil under the condition of water absorption, thereby solving a series of engineering problems caused by the expansion of the expansive soil due to water absorption.

Description

technical field [0001] The invention relates to a tester for three-way water absorption swelling rate and swelling force of expansive soil in the field of civil engineering geotechnical tests. Background technique [0002] General test The instrument for measuring the water-absorbing swelling force of expansive soil is mainly the expansion rate and expansion force under specific loads and confined conditions in soil mechanics. The size of the cylindrical sample is The height is 20mm, the soil expands when it encounters water, and the expansion force is obtained by applying an external load to constrain the vertical deformation of the sample through the principle of leverage. In addition, some scholars use a triaxial compression strength tester to test the vertical expansion rate and expansion force. This instrument can provide lateral water pressure, and the sample swells by absorbing water from the bottom. [0003] For the existing technology of testing expansion stress a...

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Problems solved by technology

[0003] For the existing technology of testing expansion stress and strain, conventional high-pressure consolidation instrument and triaxial strength tester, high-pressure consolidation instrument is mainly used to test the equilibrium expansion force of expansive soil in the test, which has the characteristics of fast, simple and efficient test , it is determined that the determination of the three-dimensional expansion rate and expansion force of expansive soil cannot be simulated. At the same time, due to the principle of leverage, the small angle difference of the force arm will cause uneven force on the sample, and the accuracy needs to be improved.

[0004] The purpose of the triaxial strength tester is to test the compressive strength of expansive soil. Its lateral force system uses a servo to keep the lateral load of the sample constant. Therefore, for the airtightness of the pressure chamber, the triaxial instrument cannot Guaranteed, this point is applied to test the expansion rate and expansion force of expansive soil can not meet

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