SU1689652A1 - Method of determining moisture content of compacted ground - Google Patents

Abstract

The invention relates to construction, to methods for monitoring the state of soil compacted. The purpose of the invention is to expand the range of application and increase accuracy. The method includes determining the calibration dependence of the depth of the probe on the density of the soil at its optimum humidity, sampling from compacted soil, compacting it to the maximum density (dx) and immersing the probe in it with the definition of h. In addition, the calibration dependence of the maximum density on humidity is determined, and the moisture content of the compacted soil is determined by the above calibration dependencies, the value of Mmoch., H. 2 Il. S (L S

Description

The invention relates to the construction and can be used to control the quality of soil compaction in the production of road construction and hydraulic works.

The purpose of the invention is to expand the range of application and improve accuracy

FIG. 1 is a plot of the maximum volumetric mass of moist soil, here moisture W; in fig. 2 is a graph of the depth of immersion at a given number of impacts of the conical probe h versus the bulk density of the soil, o, at the optimum humidity WonT,

The method is carried out as follows.

From the layer of compacted soil, a sample is taken, which is placed in layers in a standard compaction instrument and compacted in layers with an equal number of strokes. The dimensions of the glass of the standard compaction instrument take an internal diameter of 100 mm, a height of 127 mm, a weight of a falling weight of 2.5 kg, a height of fall of 300 mm.

The number of soil layers is assumed to be 3, and the number of impacts for sands and sandy loams to 20 on each layer. At the same time, the compaction is performed until the maximum density is reached (the bulk density of the wet soil), which is controlled by stopping the movement of the guide rod of the standard compaction instrument.

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The bulk density of the wet soil is determined by weighing, and the volume of the soil is determined by direct measurement of the height of the soil in the canal.

Then, according to the calibration dependence of the standard compaction of this soil, m0. According to the dependence of the maximum value of the density with a successful load on the soil moisture obtained at the site of the experimental compaction, the possible values of the moisture of the compacted soil are determined (Fig. 1).

As can be seen from the graph (Fig. 1), to one value of the bulk mass of the wet soil MJ, two possible values of the weight moisture of the compacted soil W and Wg correspond. In practice, the visual selection of one of the possible values of humidity is difficult

not, especially in the range of values close to the value of the optimal humidity WDrrr

To uniquely determine the moisture content of compacted soil, the dependence of the parameters of soil probing in a glass of a standard compaction instrument on the soil moisture is used (Fig. 2). This dependence is obtained at the site of the experimental compaction, and the graph is plotted for the values of the bulk density of the soil, obtained at its optimum moisture content. In practice, a drummer is used for this purpose, in which the mass of the load and the height of its fall are identical with these parameters in the standard compaction device, which simplifies the implementation of the proposed method.

If the depth of the probe with a known value of the bulk mass of wet soil is greater than it should have been at optimum humidity, then the actual value of humidity is more than optimum. This allows one of the two humidity values Vfy and W to select the value Wont (Fig. 1). In the opposite case, choose the value of W WonT

The method allows the determination of humidity for all types of sandy and clayey soils without limiting the humidity range, and taking into account the actual maximum density of the soil provides an increase in the accuracy of measurements.

Claims (1)

Invention Formula A method for determining the humidity of a soil that is primed, including pre-compaction of soil samples with optimum humidity to different densities, the introduction of a probe into them at a given number of impacts with the determination of the depth of its immersion and the construction of a calibration dependence, the sampling of soil from the compacted layer, seal it up to mac5 maximum density, the introduction of a probe into the sample at the same number of impacts with the determination of the depth of immersion and the determination of the moisture content of the compacted soil from the data obtained using the calibration dependence, characterized in that, in order to broaden the range of application and improve accuracy, Standard compaction of soil samples of the compacted layer at different values of humidity with the construction of a calibration dependence; after compaction of the soil sample to the maximum density, its value is measured, which This is used to determine the approximate humidity values for the additional calibration dependence, and the final humidity value is determined by comparing the depth of the probe probe for the sample compacted to the Maximum density with the value of the same parameter of the same soil density with the optimum humidity according to the corresponding calibration dependencies. humidity values. five 6.0  5.0: I § 1.0 WN & thirty J tflI Ј 1.0 Wtwonm four / 1.61.7 1.81.92.0 2.1 Volumetric mass of wet zpyf / ma y0, p / cm $ Editor L. Volkova Compiled by G. Martynov Tehred A. Kravchuk Correct Su 15202550 Weighing well and osgpi,% fi% / / / four / Proof-reader I. Erdeyi