Testing method for simulating soil cutting effect indoors by using high pressure jet grouting technology

Abstract

The invention discloses a testing method for simulating a soil cutting effect indoors by using a high pressure jet grouting technology, comprising the steps of: putting an onsite soil sample into test equipment; sequencing rotating speeds and lifting speeds to be checked, selecting a first group of rotating speeds and lifting speeds, switching on a power supply, sequentially starting the test equipment, wherein a pore water pressure sensor generates a pressure signal during the testing process, and the signal is received and recorded by a pressure monitoring system, and the first group of tests is finished after a jet grouting rod rotates a circle; discharging water in the soil after the first group of tests is finished, digging out a soil body, keeping the pressure and the flow rate and repeating the groups of tests; and drawing the average value of pore water pressure data during the testing process of the groups to a graph. The method disclosed by the invention can monitor the change conditions of the soil cutting effect of high pressure water under different rotating speeds and lifting speeds of the jet grouting rod in real time so as to obtain the rotating speed and the lifting speed under the optimal soil cutting effect and reasonably select jet grouting construction parameters.

Description

technical field [0001] The invention relates to a test method in the technical field of construction engineering, in particular to a test method for indoor simulation of the soil-cutting effect of high-pressure rotary spraying technology. Background technique [0002] With the continuous development of my country's infrastructure construction, high-pressure rotary grouting construction technology has been widely used in underground engineering, such as the protection piles around the foundation pit, the reinforcement of the entrance and exit holes of the shield machine, etc. The high-pressure rotary grouting construction technology is to use drilling rigs and other equipment to drive the drill spray rod into the formation, and then the high-pressure cement slurry enters the drill spray rod from the slurry inlet on the drill spray rod through the high-pressure grouting hose, and is installed on the drill spray rod. The nozzle sprays out the cut soil, and at the same time rota...

AI Technical Summary

Problems solved by technology

The construction parameters of high-pressure rotary spraying technology mainly include injection pressure, flow rate, rotation speed, lifting speed, etc. Whether the selection of these construction parameters is reasonable or not has a crucial impact on the treatment effect of the formation. Unreasonable selection of construction parameters will not only waste construction resources , it is more likely to bring poor foundation treatment effect, thus causing engineering accidents

[0003] Among the construction parameters of high-pressure rotary grouting, the selection of rotation speed and lifting speed is not only related to the speed of construction efficiency, but also related to the effect of foundation treatment. However, there is no unified consideration for the two in the construction design of high-pressure rotary grouting technology. Regulations or methods are basically based on engineering experience, so the uncertainty is relatively high

The domestic research work on the influence of the change of the drilling and spraying rod rotation speed and lifting speed on the effect of foundation treatment is still in its infancy, and there is still a lack of reasonable selection of the drilling and spraying rod rotation speed and lifting speed in the high-pressure rotary grouting construction. The results of the research on the best soil cutting effect

[0004] In order to carry out in-depth research on the influence of the rotation speed and lifting speed of the drilling spray rod on the formation treatment effect of the high-pressure rotary grouting technology, in order to meet the requirements of obtaining a reasonable rotation speed and lifting speed in the actual construction of high-pressure rotary grouting, and to achieve reasonable For the purpose of allocating construction resources, it is necessary to have an indoor test method for simulating the soil cutting effect of high-pressure rotary spraying construction technology. At present, the existing technology is still blank in this field.

Images