Arrangement method of exploration survey lines for railway tunnel with airborne electromagnetic method

Abstract

An arrangement method of exploration survey lines for a railway tunnel with an airborne electromagnetic method effectively explores geological conditions of a underground section at a center line of arailway line, so as to ensure reliability of geophysical data and realize economical efficiency, rationality and high efficiency of the exploration project as best as possible. The exploration surveylines comprise a central survey line arranged at the center line of the railway line; a left-side survey line group and a right-side survey line group that are arranged on the left side and the rightside of the center line in the direction of the railway line respectively. In the left-side survey line group and the right-side survey line group, the survey lines are symmetrically arranged with respect to the central survey line, and the spacing between the survey lines at the same side is gradually changed from the smallest spacing between the survey lines closest to the central survey line to the largest spacing between the survey lines farthest away from the the centrak survey line. The spacing between the survey line nearest to the edge in the left-side survey line group and the surveyline nearest to the edge in the right-side survey line group is twice as much as the depth of tunnel exploration. The lengths of the central survey line, the survey lines in the left-side survey linegroup and in the right-side survey line group are the sum of the tunnel length and the length of extended segment extending outward from both ends of the tunnel.

Description

technical field [0001] The invention relates to the field of applied geophysics, in particular to a method for arranging detection lines of railway tunnel airborne electromagnetic survey. Background technique [0002] The main line of the Ya'an-Linzhi section of the Sichuan-Tibet Railway is about 1,000 kilometers long, of which the total length of the tunnels is about 800 kilometers, and the ratio of tunnels to lines is as high as 80%. The line crosses the Hengduan Mountains and crosses the Jinsha River, Lancang River, and Nujiang River. It is the most dangerous railway in the world. The terrain along the line is steep and the problems of high cold and hypoxia are extremely prominent. A considerable number of personnel in the tunnel section cannot reach the line for ground geophysical survey work. Data gaps are expected to occur in 60% of the paragraphs. [0003] Airborne geophysical prospecting methods are divided into four categories: airborne gravity, aeromagnetic, aeron...

AI Technical Summary

Problems solved by technology

If the surveying lines are arranged at equal intervals according to the above-mentioned mineral resources exploration method, when the conditions for the exploration accuracy of the underground section of the tunnel center line are met, the surveying line spacing is required to be small and the number of surveying lines is large, but the exploration cost is high

If the survey line spacing is large, the number of survey lines is small, and the detection cost is low, but the survey accuracy of the centerline underground section cannot be satisfied

Images