Abstract:
In order to discuss the design rationality of the overall construction scheme for the super-long highway tunnel with auxiliary adit, and accurately control the construction period and cost, the principles of construction with the help of auxiliary adit are discussed, the auxiliary construction efficiency and construction cost per linear meter by using shaft are calculated, the designed water inflow volume for shaft in case of adverse grade construction is estimated, and it comes the following conclusions: (1) it is necessary to use auxiliary adit to assist the construction of tunnels with distance of blind heading more than 5,000 meters or tunnel length larger than 10,000 meters, and the ventilation shaft should be given a priority as an auxiliary adit if it is set for operation ventilation; (2) the auxiliary construction by vertical shaft (inclined shaft with rail) is expensive and its lifting capacity is limited, the trackless in? clined shaft, parallel adit or cross passage should be chosen preferably regarding the auxiliary construction of tunnels and the slope should be controlled within 12.3%; (3) on the basis of predicted water inflow volume and the assumption of homogeneous aquifer, the calculation method of designed water inflow volume during construction and the rational allocation of drainage facilities are given.
TANG Xie1 LIN Guojin1,
2 HE Jia1 WANG Jun1
.Design and Practice of Auxiliary Construction Scheme for Micangshan Tunnel Using Ventilation Shaft[J] MODERN TUNNELLING TECHNOLOGY, 2020,V57(4): 12-19