Method for monitoring deformation of pile body of cantilever fender post of deep foundation pit

Abstract

The invention discloses a method for monitoring deformation of a pile body of a cantilever fender post of a deep foundation pit, which comprises the following steps of: (1) excavating a first section of station foundation pit according to a design scheme; (3) respectively installing a plurality of positioning devices which are arranged along the vertical direction on each reinforced concrete pile, and regularly measuring the coordinates of each positioning device by adopting a total station; (4) transmitting the coordinates of each positioning device obtained in the step (3) to a computer system, and (5) continuously excavating the station foundation pit downwards in sections, and monitoring the displacement condition of the reinforced concrete piles at each stage according to the methods from the step (2) to the step (4) until the construction of the station is finished. The method is easy to operate, economical and reliable, whether the foundation pit fender post is in danger or not can be found in time, the safety and stability of a foundation pit are judged, and construction safety is guaranteed.

Description

technical field [0001] The invention relates to the technical field of construction monitoring and measurement, in particular to a monitoring method for the deformation of cantilever enclosure piles in deep foundation pits. Background technique [0002] At present, the enclosure construction of subway stations mainly includes bored pile enclosure structure, ground connection wall enclosure structure, and direct grading and excavation. For the bored pile enclosure structure, the process of constructing the bored pile + inner support structure first, then constructing the station, and finally constructing the tunnel section is adopted. In order to ensure the safety of the overall construction, it is necessary to pre-embed the pile body inclination pipe in advance when constructing the enclosure pile, and monitor the displacement of the pile body during the construction station. However, in some cases, the sequence of construction is changed, for example, the fencing piles are...

AI Technical Summary

Problems solved by technology

This construction method will cut off the retaining pile b in the excavation area of ​​tunnel a (see figure 1 , 2 ), resulting in the destruction of the pre-embedded pile inclinometer tube, making it impossible to monitor the deep horizontal displacement of the pile in the foundation pit by conventional methods

In addition, the truncated retaining pile is divided into upper and lower sections by the tunnel, and the middle part is suspended, which is more prone to displacement. When the displacement of the cantilever pile cannot be understood in time and accurately, the stability of the foundation pit cannot be accurately reflected. Early warning of the safety of the foundation pit in advance, resulting in a huge safety hazard in the foundation pit of the station

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