Underwater Pile Foundation Low Strain Measurement Device

Abstract

The invention discloses an underwater pile foundation low strain dynamic testing device. A knocking hammer and a stress wave receiving probe are integrated in one stress wave generating and receiving device. Meanwhile, the automated falling and retracting of the knocking hammer are achieved. The stress wave generating and receiving device is fixed to the top of a pile foundation through the combination of a balancing weight and a fixing device. An adhesive attachment gelatinous layer is arranged at the lower end of the stress wave receiving probe. A water isolation door which can be opened and closed is designed in the lower portion of a left cavity. When the stress wave generating and receiving device is pressed on a pile, a frame block is pressed on the pile and sealed together with a pile cap, and the water isolation door is then opened. By means of the structure, the left cavity can be kept in the non-water state all the time, and the phenomenon that the knocking effect is influenced when the knocking hammer falls and rubs water is avoided. The stress wave generating and receiving device is provided with a pile hooking structure, wherein the pile hooking structure comprises a pile grabbing device. The underwater pile foundation low strain dynamic testing device has the advantages that the underwater pile foundation low strain dynamic testing device can be used in deep water under high pressure, the knocking hammer and the detection probe are combined, the knocking hammer can knock on the pile under the water-free environment, and the stress wave generating and receiving device is good in fixing effect.

Description

technical field [0001] The invention relates to the technical field of pile foundation detection, in particular to a pile foundation detection device in a high water pressure environment, in particular to an underwater pile foundation low strain detection device. Background technique [0002] Large-diameter cast-in-situ piles are widely used because of their high bearing capacity and low construction noise. They are usually excavated manually or drilled into holes and poured into piles underground or underwater. The quality is affected by the construction process, especially the concrete pouring. It is difficult to control due to the influence of various factors such as working procedures, so the quality problems of pile foundations generally exist, such as too thick sediment, uneven pile body (local mud, segregation, honeycomb, etc.). Therefore, before proceeding to the next process, the quality and integrity of the concrete body of the pile must be inspected and evaluated,...

AI Technical Summary

Problems solved by technology

However, the existing low-strain dynamic measuring instrument is not suitable for use in deep water. On the one hand, when using the dynamic measuring instrument for detection, two people are generally required to cooperate. One person presses the probe on the pile head, and the other hand The hand hammer or power hammer hits the top of the pile to generate a stress wave, and another person initially judges whether the curve is qualified through the display of the pile detector connected to the probe, and records the corresponding pile number, and then uses special software to further analyze the data; On the other hand, in the deep water high pressure environment, the use of artificial diving for low-strain operations is not only high in labor costs, complicated and difficult to operate, but also the probe of the dynamic tester will seep into the water under the high pressure of deep water, resulting in a decrease in the sensitivity of the probe, and the low-strain curve knocked out Distorted messy, poor results

Expensive labor costs, high difficulty of detection and poor detection effect severely limit the application of low-strain dynamic detectors in marine and river-sea pile foundation detection

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