Application of WSS construction method in shield end reinforcement of water-rich sand layer

Abstract

The invention provides an application of a WSS construction method in shield tool changing reinforcement of a water-rich sand layer. A WSS construction method grouting technology is characterized in that an underground drill rig is used for deep- hole grouting and reinforcement and solution-type grout composed of a solution A and a solution B is used firstly for back grouting and soil body drainage, so that soil body impermeability can be enhanced; and after completion of the back grouting construction of a whole reinforcement body with application of the solution-type grout composed of the solution A and the solution B, turbid-type grout composed of the solution A and a solution C is used for forward grouting and soil body solidification, so that physical natures of the original soil body can be changed and compressive strength of the soil body is increased. Finally, a soft soil layer (which is mainly composed of sandy soil, gravelly clayey soil and sand layers) becomes a soil body with the high impermeability, the high compressive strength and high stability. Hence, concrete grouting inspection and tool replacement become more convenient.

Description

technical field [0001] The invention relates to the shield technology, in particular to the application of a WSS construction method in the reinforcement of the end of the shield in the water-rich sand layer. Background technique [0002] The traditional shield end reinforcement methods include stirring pile method, rotary spraying pile method, stirring + rotary spraying pile method, SMW pile method, sleeve valve pipe grouting method, manual hole digging pile method, etc. The more commonly used reinforcement methods are stirring pile method Pile method, rotary spray pile method, mixing + rotary spray pile method. For water-rich sand layers, the most commonly used method is the jet jet pile method. [0003] In the construction of Longjing Station in the shield section of Shenzhen Metro Line 7 7301-1 undertaken by our company, the original design plan was to use single-row double-pipe jet grouting piles ￠600@450 for reinforcement. The reinforcement range and depth of penetrat...

AI Technical Summary

Problems solved by technology

[0007] 3. Judging from the current situation of shield tunneling on Shenzhen Metro Line 7, the use of high-pressure rotary grouting piles for reinforcement will cause a large amount of water and mud gushing, and the risk is relatively high

[0008] 4. The cost is high, the verticality deviation control of the pile driver is difficult, the water stop control between the piles is poor, and it is not suitable for the upper soft and lower hard strata

Images