Borehole transient electromagnetic detection method for cast-in-place pile reinforcement cage length

Abstract

The invention provides a borehole transient electromagnetic detection method for cast-in-place pile reinforcement cage length. The method includes the steps that a drill hole parallel to the center line of a pile body is formed in a cast-in-place pile or the periphery of the cast-in-place pile; an instrument for detection is well installed and debugged, a borehole probe of the instrument is placed into the drill hole and connected with a host; the host is started, point distances are well selected within the range of 0.20-0.50m to be used as detection points of different depths, and the induced electromotive force of a secondary electromagnetic field is sequentially measured from top to bottom or from bottom to top; measured data is input into a computer from the host to be processed; a plurality of induced electromotive force-depth curve cross-section diagrams are formed by the data processed through software, accordingly the position of the top end of a reinforcement cage, the position of the bottom end of the reinforcement cage and the length of the reinforcement cage are judged, then the length of the reinforcement cage is compared with the length of a designed and constructed reinforcement cage, errors are calculated, and whether the reinforcement cage meets the design requirements or not is judged. The detection method is high in accuracy, high in resolution capability, short in detection period and low in detection cost.

Description

technical field [0001] The invention relates to the field of civil engineering building foundations, in particular to a transient electromagnetic detection method carried out in a cast-in-situ pile reinforcement cage length well. Background technique [0002] Guangdong Province is the province with the most developed expressways in the country, and the expressway mileage that has been opened to traffic is nearly 5000km. Guangdong has always been a major province of bridges in the country, and the proportion of bridges is very large. With the increase of highway network density and the increase of difficulty in land acquisition and demolition, the proportion of bridges will become larger and larger. For example, individual highways The proportion of bridges in the project has reached as high as 85%. At the same time, due to the convenient construction of prefabricated beams and slabs, economical and practical, small-span bridges are widely used in engineering practice, and a ...

AI Technical Summary

Problems solved by technology

If the response characteristics of the curve are not given when the effective magnetic inclination is positive or negative, different geomagnetic backgrounds will have a certain impact on the test data, resulting in errors or even errors in the interpretation of the measured data

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