Analysis of influence zone division of adjacent construction of underwater tunnel based on Hoek-Brown criterion

Compared with normal tunnels, the problem of the adjacent construction of the underwater tunnel is more complicated. The empirical method of influence zone division of adjacent tunnel construction has great uncertainty so far, thus it’s meaningful for construction and design of tunnels to calculate the influence zone accurately and theoretically. Based on Hoek-Brown nonlinear yield criterion, considering the factor of seepage water, the stress state of surrounding rock and soil of underwater tunnel is calculated through elastic-plastic theory, furthermore the influence zone division method of adjacent construction of underwater tunnels is proposed, and combined with one engineering project, the calculation results are applied and compared by numerical simulation test. The conclusions show that: the derived calculation formula can be used to get demarcation radius among strong influence zone, weak influence zone and non-influence zone of adjacent construction of underwater tunnel by using the computer program. The conclusions can be applied to guiding the underwater tunnel supporting design and construction.