The method of carrying out engineering-geological survey

 

The invention relates to the engineering-geological surveys to obtain data on the structure of the upper part of the section (high frequency resolution) of rocks to issue recommendations for the construction of engineering structures, primarily in the areas of crossings over water obstacles. Effect: improve the accuracy of selecting blocks of rocks with different resistance on the parts of the crossings over water obstacles. The inventive method includes a vertical electric sounding (VES), circular Mikroelektronika sensing, validation of measurements and the construction of a geoelectric section. Before VES conduct electrical profiling for each of the alternatives in the area of research. VES carried out perpendicular to the target crossing the water obstacle. Perform on both sides of the water obstacles circular Mikroelektronika sensing, followed by VES bottom of water hazards. Then on the area of research performed along the competing variants circular Mikroelektronika sensing. The data and build the geoelectric section. 1 C.p. f-crystals, 1 Il.

The invention relates to the engineering-geological surveys for the floor is hanicheskih structures, primarily in the areas of crossings over water obstacles.

The known method engineering and geological surveys using GPR vertical electrical sounding (VES), allowing to obtain the necessary amount of information about the studied section in normal conditions (the“Prospecting”. Handbook of Geophysics. - M.: Nedra, 1980, S. 64-71, 82-106).

However, when working in areas of crossings over water obstacles specified method gives large errors in obtaining information about the studied section.

There is also known a method of carrying out engineering geological surveys, including vertical electric sounding, cross VES (LSC) to determine the depth location of the surface layers at shallow depths studies (“Prospecting”. Handbook of Geophysics. - M.: Nedra, 1980, S. 466-468).

But this method doesn't allow the cut with sufficient accuracy lots of rocks with different resistance on the parts of the crossings over water obstacles.

Closest to the proposed by its technical essence is a way of carrying out of engineering and geological surveys, including vertical electric sounding (VES), the unwinding of the line AB and MN, cresa (RF Patent No. 2080626, G 01 V 3/04, published. 27.05.97, bull. No. 15).

This method also does not allow you to highlight in the context with sufficient accuracy lots of rocks with different resistance on the parts of the crossings over water obstacles.

The task to be solved by the invention, is to improve the accuracy of selecting blocks of rocks with different resistance on the parts of the crossings over water obstacles.

The solution of this problem is achieved in that in the method of conducting geotechnical investigations, including vertical electric sounding, the unwinding of the lines AB and MN, circular Mikroelektronika sensing measurements and the construction of a geoelectric section, before unwinding of the lines AB and MN carried out the electrical profiling for each of the alternatives in the area of research. Carry out the unwinding of the lines AB and MN perpendicular to the target crossing the water obstacle. Perform: on both sides of the water obstacles circular Mikroelektronika sensing, followed by VES bottom of water hazards. Then on the area of research performed along the competing variants circular Mikroelektronika sensing and the data obtained are building resistivity RA is the target crossing the water obstacle zones of different size (high and/or low) resistance, meet certain tectonic conditions of occurrence of the rocks.

With the aim of identifying areas of change in the intensity of the electric resistance as at different depths (levels), and throughout the length of the competing variants electrical profiling is desirable to perform not less than duchesneau (mnogorazemny) installation.

The implementation of the unwinding of the lines AB and MN is perpendicular to the line of crossing of water obstacles helps to avoid errors in the measurement of electrical resistivity of rocks associated with surface irregularities in the area of research and slope of the land surface.

Execution on both sides of the water obstacles circular Mikroelektronika sounding sets the degree and the predominant direction of horizontal heterogeneity of the section.

The VES bottom water hazards is to determine the lithological composition of sediments.

And execution in the area of research along competing options (target crossing water obstacles) additional Mikroelektronika soundings allows you to evaluate the power and lithological composition of the sediments.

On the basis of the received data is a forecast about is illustrated in the drawing and is implemented as follows.

Competing options 1 on the area of study 2 conduct an electrical profiling install not less than duchesneau (not shown).

According to the obtained results choose point 3 vertical electrical sounding, which carry out the unwinding of the lines AB and MN, respectively 4 and 5.

The unwinding of the lines 4 and 5 is carried out perpendicular to the line of passage 6 through the water obstacle 7.

Perform on both sides of the water obstacles 7 circular Mikroelektronika sensing Kumquat (AB/250 m) to highlight the area and volume plots of rocks with different resistance.

Then produce VES bottom 8 water hazards 7 (if AB50 m) with floating or bottom installation 9.

Then on the area of study 2 along competing options 1 perform circular Mikroelektronika sensing.

According to a study in construct charts and tables that summarize information about the distribution of the electric resistance on the surface and in the inner points of the studied geoelectric section.

And on the basis of the obtained data about the changing parameters of the studied section forecast of laying the foundations for the construction of the La inventions

1. The method of carrying out engineering-geological researches, mainly in the areas of crossings over water obstacles, including vertical electric sounding (VES), circular Mikroelektronika sensing and the construction of a geoelectric section, characterized in that in the area of research conduct electrical profiling for each of the alternatives, perform vertical electric sounding perpendicular to the target crossing the water obstacle, carried out on both sides of the water obstacles circular Mikroelektronika sensing, followed by VES bottom water obstacles, then the area of research performed along the competing variants circular Mikroelektronika sensing and the data obtained are building geoelectric section.

2. The method according to p. 1, characterized in that the electrical profiling conducted not less than duchesneau installation.

 

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