Method for judging reinforcement stability of long pipe shed in tunnel intrusion contact zone

Abstract

The invention relates to a method for judging the reinforcement stability of a long pipe shed in a tunnel intrusion contact zone, and belongs to the field of tunnel foundation construction. The distance z from the ground of the intrusion contact zone to a tunnel vault, undrained shear strength cu of a soil body in the intrusion contact zone, thickness dz of the long pipe shed after grouting, diameter d1 of a steel pipe of the long pipe shed, wall thickness delta, shear strength cp of the long pipe shed, shear strength cc of a grouting body, average shear strength cc and p of the long pipe shedand the grouting body after weighted averaging according to area, shear capacity Kj of the long pipe shed, perimeter L of a cross section of the grouting body of the long pipe shed, length Ld1 of a shorter side of the long pipe shed embedded in a surrounding rock on the inner side of the intrusion contact zone, length Ld2 of a shorter side of the long pipe shed embedded in the surrounding rock onthe outer side of the intrusion contact zone, shear strength t1 between the grouting body of the long pipe shed and the surrounding rock on the inner side of the intrusion contact zone, shear strength t2 between the grouting body of the long pipe shed and the surrounding rock on the outer side of the intrusion contact zone, and reinforcement carrying capacity K of the long pipe shed are determined in sequence, and the reinforcement stability of the long pipe shed in the tunnel intrusion contact zone is judged to avoid slump of the intrusion contact zone.

Description

technical field [0001] The invention relates to a method for judging the reinforcement stability of a long pipe shed in a tunnel intrusion contact zone, belonging to the field of tunnel foundation construction. Background technique [0002] In the contact zone between volcanic rock and sedimentary rock, due to strong intrusive extrusion and thermal erosion, there is often an intrusive contact zone at the contact position. The intrusive contact zone is often in the shape of fragments, sandy soil or clay, with low strength and high water content. When the tunnel is excavated through the intrusion contact zone, if the intrusion contact zone is not reinforced, disasters such as landslides and water inrush are prone to occur. Among various reinforcement methods, the reinforcement of the long pipe shed is one of the commonly used measures. The long pipe shed is penetrated, and then the tunnel is excavated after grouting in the long pipe shed, which can greatly improve the stabili...

AI Technical Summary

Problems solved by technology

The bearing capacity of the long tube shed includes two types: shear bearing capacity and tensile bearing capacity. If one of them fails to meet the requirements, the long tube shed will be damaged, resulting in slumping of the intrusive contact zone above.