The Application Of TEM Method In The Engineering Investigation

Since the 1980 s,China's highway construction has been advancing by leaps and bounds.The design theory has increased dramatically.The construction level has achieved leap-forward development and has played an important role in China's transportation system.However,the excessively fast construction speed often results in incomplete detection of the roadbed in the early period,leading to problems in later operations.In recent years,reports such as the collapse of highways and the collapse of urban roads have emerged in an endless stream.These disasters have seriously affected people's normal travel.Therefore,how to carry out reasonable tests and prevent disasters before they occur is an urgent matter.This article is aimed at the issue of highway exploration.It is intended to find an effective and efficient geophysical method that can eliminate faults in a timely manner through regular surveys.However,many current methods of geophysical exploration have certain limitations.For example,the gravitational and magnetic methods have weak anti-interference ability.They are not suitable for road environments with severe human noise;earthquakes,high-density isoelectric methods destroy the environment,and ground penetrating radar measurements Shallow depth and other issues.After many demonstrations and engineering examples,the transient electromagnetic method can avoid the destruction of the environment and has strong anti-noise ability.It is a very effective result of highway survey.In recent years,the application of mathematics models and the improvement of the interpretation level have made geological problems that transient electromagnetic methods can solve more and more.It is not only widely used in the exploration of mineral resources,but also in the municipal engineering,environmental monitoring,etc.,has also been a very good development.Taking into account the special nature of the highway environment,the scope of the survey area is narrow,and the depths of targets,such as voids and culverts that cause road collapse,are relatively shallow,and power frequency interference and humanistic noise are unavoidable.In view of the above problems,this paper starts from the theory of transient electromagnetic theory,introduces the principle of transient electromagnetic theory,the definition of early and late apparent resistivity,and gives the OCCAM inversion process and algorithm.In the example verification,designing a mobile wireframe measurement system can achieve advantages such as high production efficiency,abundant shallow information,and strong anti-interference ability.Through the interpretation of results,a number of hollow anomalies were delineated,and more than 30 boreholes were drilled in the delineated anomaly area.All boreholes encountered voids within a specified depth range.Judging the cause of subsidence provides a strong basis for the targeted treatment of collapsible loess layers targeted by the conservation units in the section.