Standard penetration test apparatus and test method thereof

Abstract

The invention provides a standard penetration test apparatus and a test method thereof. A standard penetration device of the standard penetration test apparatus is sequentially connected with an air hammer and a sounding rod; the other end of the sounding rod is connected with the air outlet of a three-way electromagnetic valve through an air transmission rubber hose; the air inlet of the three-way electromagnetic valve is connected with the air outlet of an air source treatment triplet, and the air inlet of the air source treatment triplet is connected with a small-sized air compressor; a counter and a depth recorder are arranged on one side of the upper end part of the sounding rod; an air hammer control instrument is electrically connected with the three-way electromagnetic valve and the counter, and the counter is electrically connected with the depth recorder. The invention has the benefits that the penetration test apparatus is simple in structure and convenient to operate, and data obtained through a test is accurate and reliable; and as the sounding rod does not perform impacting, absorption to impacting energy by deformation of the sounding rod is eliminated, and energy loss generated by friction of a pore wall and the sounding rod in bending deformation is avoided, so that the standard penetration test apparatus can perform effective tests in the deeper stratum without rod length correction.

Description

technical field [0001] The invention relates to a geotechnical engineering in-situ test device and a test method thereof, in particular to a standard penetrometer and a test method thereof. Background technique [0002] Standard penetration test is a commonly used in-situ test method in engineering survey, especially suitable for sandy soil formations where it is difficult to obtain undisturbed samples. The test mechanism of the standard penetration test is to use a heavy hammer with a mass of 63.5kg to fall freely according to the specified drop distance (76cm), drive a penetrator of standard specifications into the soil, and judge according to the number of hammers driven into the soil at 30cm Engineering properties of soil. Standard penetration tests can indirectly determine the compactness of sandy soil, the state of cohesive soil, unconfined compressive strength, foundation bearing capacity, and soil deformation parameters, as well as estimate pile foundation bearing c...

AI Technical Summary

Problems solved by technology

It is generally believed that the current standard penetration tester is only suitable for formations with a depth of less than 20m, and its test depth cannot meet the requirements of high-rise buildings, high-standard railways, highways, etc. for foundation test depth

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