Testing method for fine-grained soil compaction degree

Abstract

The invention relates to a testing method for the fine-grained soil compaction degree. The testing method comprises the following steps that a target backfill soil sample is selected, the selected soil sample is manufactured into five to nine sets of soil samples different in water content, the indoor moisture-density test is conducted, and the different water contents, the corresponding dry density value and the maximum dry density value are obtained; the penetration resistance values of the soil sample under different water contents and different blow counts in the first step are tested; the regression analysis is conducted on the recorded water contents, dry density value and penetration resistance values, and a regression relational expression is obtained; one test face is selected in the filling site, the quick penetration test is conducted 5-9 times, and the penetration resistance value every time is recorded; digging is conducted to the bottom of the test face in the fourth step, and the water content of the dug-out soil is tested; the relational expression in the third step is selected according to the water content value detected in the fifth step; and the average value of the penetration resistance recorded in the fourth step is calculated and then substituted into the relational expression selected in the sixth step, the dry density is calculated, and accordingly the compaction degree of fine-grained soil in the filling site is calculated.

Description

technical field [0001] The invention belongs to the technical field of fine-grained soil compaction detection, and in particular relates to a method for measuring the compactness of fine-grained soil. Background technique [0002] At present, the quality of earthwork backfill in the inspection project is mainly judged by the degree of compaction, and there are four main methods for detecting the degree of compaction: ring knife method, sand filling method, water filling method and nuclear density meter method. Among them, the first three detection methods require relatively sophisticated balances and drying equipment or burning materials to complete during the detection process, and none of them can obtain the detection results immediately on site, so they have a certain impact on the construction progress of earthworks; and Although the nuclear density meter can immediately detect the density of the unearthed soil, the nuclear density meter has a certain degree of radiation...

AI Technical Summary

Problems solved by technology

However, this method needs to re-establish the relationship between the penetration hammer number and the degree of subgrade compaction for different subgrades, and the operation is complicated and the cycle is long

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