Detecting method for pile-bottom supporting layer of mechanical pore-forming concrete filling pile

Abstract

The invention provides a detecting method for a pile-bottom supporting layer of a mechanical pore-forming concrete filling pile. The detecting method comprises the following steps: (1) uniformly placing a plurality of dual-detecting wave detectors in a peripheral direction on the bottom of a large-diameter pile hole; (2) manually exciting elastic wave on a bottom center part of the pile hole by use of an electric spark earthquake source; (3) utilizing a shallow-layer seismograph to record reflected waves received by the dual-detecting wave detectors on the bottom of the pile hole; (4) analyzing and researching waveforms of the reflected waves to judge whether the bottom of the pile hole has undesirable geological conditions such as karst caves, fluid bowls or crushed zones and the like within a certain range. According to the method provided by the invention, the bottom of the pile hole is not needed to be reconstructed for carrying out geological exploration and drilling, so that the supporting layer detecting cost is greatly reduced, and the supporting layer detecting speed is high.

Description

technical field [0001] The invention relates to the technical field of engineering construction, and relates to a method for detecting the load-bearing layer at the bottom of a mechanically pore-forming concrete pouring pile. Background technique [0002] Large-diameter bored concrete piles have the advantages of high single pile bearing capacity, good seismic performance, no noise and no vibration during construction, and have been widely used in large bridges and high-rise buildings. Due to the large-diameter piles are subjected to a large force and are crucial to the safety of buildings, the current "Code for Design of Building Foundations" (GB50007-2011) stipulates that large-diameter rock-socketed piles with single columns and single piles should be based on the nature of the rock. , to check whether there are cavity fracture zones, weak interlayers and other adverse geological conditions within the range of 3 times the diameter or 5m depth under the pile. In the prior...

AI Technical Summary

Problems solved by technology

However, in limestone areas where karst is developed or areas with complex geological conditions, it is often impossible to determine whether there are cavities, broken zones, weak interlayers and other adverse geological conditions within the range of 3 times the diameter or 5 meters depth of the entire pile bottom with only one borehole.

In order to solve the above problems, at the bottom of artificially excavated piles that can be reached manually, a new technology that combines ground radar with a small number of drilled cores to detect the bearing layer has been developed. The pile hole mechanically formed into the pile hole still needs to be further investigated by using multiple survey drilling methods. The disadvantage of this method is that the survey cost is extremely high and the survey time is long

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