Method for directly testing quality of PCC pile

Abstract

The invention relates to a method for directly testing quality of a PCC pile. In the method, pile inner soil is discharged, a testing personnel is sent to any position by a travelling cradle, whether pores, cracks, pits, indentation and intercalated mud exist inside the pile body by observing with naked eyes, a crandall is used for knocking the pile body to judge whether voids exist on the wall of the pile, an impact electric drill punctures the wall of the pile, the thickness of the wall of the pile is directly measured and compared with a pre-designed wall thickness, a concrete cutting machine cuts concrete briquette by different depths to be used in indoor concrete strength experiment. The invention overcomes the defects of the conventional testing methods for solid piles---static load test method and low strain reflection wave method of the current PCC pile quality test, such as quantities of stacking, high fee, inconvenient implementation, pile tip three-dimensional effect, high frequency interference, etc. The invention utilizes the feature of larger inner diameter of the PCC pile, has simple structure, convenient operation, easy construction and low cost, and changes pile foundation, the concealed engineering into a visible engineering by the crafty method.

Description

technical field [0001] The invention relates to a method for directly detecting the quality of piles, in particular to a method for directly detecting the quality of PCC piles. Background technique [0002] Cast-in-situ concrete large-diameter pipe piles (referred to as PCC piles) use vibration to sink the steel inner and outer double-layer casing cavity structure into the foundation design depth under the protection of the valve pile shoe closure, and flow to the structure through the concrete flow divider. Concrete is injected evenly, and then the cavity structure is removed by vibration. When the cavity structure is removed, the movable valve pile shoe structure is automatically separated to form a cast-in-place concrete thin-walled pipe pile. The outer diameter of PCC piles is generally 1.0-1.5 meters, the inner diameter is 0.7-1.3 meters, the wall thickness is 10-15 centimeters, and the pile sinking depth is 20-30 meters. [0003] After the PCC pile adopts the cast-in-...

AI Technical Summary

Problems solved by technology

The theoretical basis of low-strain detection is the one-dimensional wave theory, assuming that the pile is a one-dimensional rod, and the stress wave propagates along the pile body to meet the assumption of a plane section, which is suitable for small-diameter solid piles, but for large-diameter PCC piles, piles There is a certain included angle between the top excitation point and the receiving point, and there are differences in the velocity wave signals received by the receiving measuring points with different included angles. There are errors that affect the quality judgment of the pile body

Moreover, the velocity wave is easily interfered by high-frequency waves, and a high-frequency oscillation peak is formed between the incident peak and the reflected peak, which affects the analysis and judgment of the detected waveform

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