Method for sampling large-sized unsaturated structural undisturbed soil samples

Abstract

The invention discloses a method for sampling large-sized unsaturated structural undisturbed soil samples. The method comprises the following steps of: determining a sampling place, and artificially and transversely enlarging a working surface at a position of a designed sampling soil layer without plant root and stem, cracks, impurities or interlayer; digging the sample pit into a step shape; segmenting the step into large earthwork units from the upper layer; taking out the units integrally manually, and marking upper and lower surfaces clearly; cutting the large earthwork units into designed size soil samples by using a panel saw, and marking upper and lower surfaces clearly; coating the soil samples with a gauze, and performing wax sealing with paraffin wax; packaging by using a plastic film, filling in a carton, blocking clearances with soft materials, and sealing the carton; and conveying the carton filled with the soil samples to a road with good road condition manually, and delivering the carton. The method can minimize the disturbance degree of the soil samples, and meets the requirement that the unsaturated structural undisturbed soil samples maintains the physical and mechanical properties in sampling, protecting and transporting processes, so that the test result is more accurate.

Description

technical field [0001] The invention relates to the technical field of geotechnical engineering geotechnical tests, and relates to a sampling method, in particular to a sampling method for large-scale unsaturated structural undisturbed soil samples, which can extract large-scale unsaturated structural undisturbed soil samples under low disturbance conditions. Take it out from the original soil layer in the state, protect and transport it to the test site. Background technique [0002] In the existing undisturbed soil sample collection process, the methods that are often used are: [0003] ①At the designed sampling depth, first cut out the platform, then put on the prefabricated iron sheet square box, then continue to dig down, and slowly press the iron sheet in while digging until the soil block is slightly higher than the top edge of the iron sheet, and the soil block Dig out, smooth the upper and lower sides, cover the iron cover, seal the site with tape, fill in and stic...

AI Technical Summary

Problems solved by technology

[0006] The soil samples obtained by the above methods are small in size and the soil samples are greatly disturbed. Different soil sampling methods have a great influence on the test results and cannot well maintain the structure of the soil samples; the storage and transportation methods are in the relevant specifications. It is also not given, the preservation effect of soil samples is not good, the time is short, and the physical properties of soil samples change greatly during collection and transportation

The undisturbed samples taken by this method of taking soil and maintaining soil samples are acceptable for conventional geotechnical laboratory tests, but cannot meet the requirements of soil sample size, handling and maintenance, Disturbance degree, physical and mechanical properties maintenance and storage time requirements

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