Embedding material and method suitable for embedding earth pressure cell

Abstract

The invention discloses an embedding material and method suitable for embedding an earth pressure cell. The embedding material comprises, by weight, 0.08-0.12 part of cement, 0.16-0.28 part of bentonite, 4.6-4.8 parts of fine sand and 1.5-1.6 parts of water, and the above raw materials are mixed evenly to prepare the embedding material. The method for embedding the soil pressure cell through the above embedding material includes the following steps that firstly, mud protection wall drilling is conducted on a site where the earth pressure cell needs to be embedded, and the calibrated earth pressure cell and a support are put into a drilled hole; then a grout outlet of a grout pouring pump is connected with a hard long pipe through a soft pipe, the hard long pipe is inserted in the drill hole, a lower pipe opening of the hard long pipe goes deep into the bottom of the drill hole, and low-concentration grout is used for replacing high-concentration grout; and then the grout outlet of thegrout pouring pump is connected to the hard long pipe through the soft pipe, the grout pouring pump is started, the embedding material begins to be injected, and the hard long pipe is gradually elevated in the embedding material injecting process till the drill hole is filled with the embedding material.

Description

technical field [0001] The invention belongs to the technical field of rock and soil construction, and in particular relates to a landfill material suitable for embedding earth pressure cells and an embedding method thereof. Background technique [0002] In the construction of urban subway stations or high-rise buildings, the site is narrow and the environmental boundary conditions are complex and diverse. The excavation of deep foundation pit directly affects the safety quality, construction period and cost of the whole project. Modern deep foundation pits often use composite retaining forms such as ground connection walls, hanging wall row piles, steel sheet piles, and deep mixing pile impervious walls to prevent damage to surrounding buildings and various pipelines caused by damage to the undisturbed soil outside the foundation pit. safe use. The change of earth pressure at different depths of the retaining structure and pit wall interface is a must-measure item for ris...

AI Technical Summary

Problems solved by technology

[0003] One is that there is no effective earth pressure cell embedding method. At present, the method of drilling a lateral earth pressure cell is as follows. Drill a hole in the soil behind the wall, and then put the earth pressure cell with a fixed rate into the drill hole. If the hole is good, then fill it with fine sand. This method requires secondary drilling, which is very difficult to fill with fine sand, and the construction cost is relatively high. In addition, the drilling will cause the surrounding soil to have a soil arch effect, which will cause the surrounding soil The internal stress of the body is redistributed, and the earth pressure acting on the arch or on the arch is transmitted to the arch foot and the surrounding soil, resulting in inaccurate test results

[0004] Second, there is a lack of a material suitable for earth pressure box landfill. The remaining space of the buried hole of the original earth pressure box is small, and the mud in the drill hole makes it impossible to directly or pump backfill fine sand. Therefore, it is necessary to improve the landfill material Properties, 1) It needs to have sufficient pumping fluidity within 1 inch pipe diameter, 2) It needs to have easy drainage and rapid strength growth characteristics, 3) It cannot form a structure, and its strength should not be too low, which will affect the earth pressure box. Strength, strength characteristics should be close to fine sand, 4) low cost

According to the survey, no one has used other landfill materials in the original borehole of the pressure box

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