Construction method and structure for reinforcing unloading pit bottom above tunnel foundation pit

• Main Authors: LIN MEIHONG, WEN CHENGYONG, YING ZONGQUAN, WANG XUEGANG, WANG HAIYANG
• Format: Patent
• Language: Chinese; English
• Published: 26.07.2024
• Subjects: EMBANKMENTS; EXCAVATIONS; FIXED CONSTRUCTIONS; FOUNDATIONS; HYDRAULIC ENGINEERING; SOIL SHIFTING; UNDERGROUND OR UNDERWATER STRUCTURES

The invention discloses an unloading pit bottom reinforcing construction method and structure above a tunnel foundation pit. The method comprises the steps that foundation pit support structures are constructed on the two sides of a to-be-excavated range of a foundation pit above an existing tunnel; soil body excavation is carried out in the to-be-excavated range of the foundation pit, vertical supports are arranged while excavation is carried out, and after soil body excavation is carried out, back pressure construction is carried out on the area where soil body excavation is completed; when excavation is conducted to the bottom of the designed foundation pit, grating reinforcement is conducted on soil on the periphery of the existing tunnel through cement mixing piles, so that a cement mixing pile grating body is formed; a drainage layer is arranged above the cement mixing pile grating body, and meanwhile a cushion layer is laid; a structural bottom plate is poured on the cushion layer; and an anti-pulling