Abstract: In conventional design, anchor bolt spacing and length are invariable along the arch wall of a largespan and large crosssection tunnel, increasing cost and causing waste. Numerical simulations and site monitoring are used to study the stress variation characteristics of anchor bolts and the final stress state of each part during partial excavation of a shallowburied fourtrack railway station tunnel on LiupanshuiZhanyi railway with a large span and large crosssection, as well as the characteristics of axial force distribution of systematic anchor bolts. The following conclusions are drawn: (1) the axial force of a systematic anchor bolt varies with its location, and the axial force of a systematic anchor bolt is the greatest at the sidewall, followed by the arch shoulder, and the smallest at the crown; (2) inequable support parameters can be used according to the characteristics of axial force of a bolt; (3) the use of inequable support parameters in a largespan and large crosssection tunnel can help in reducing cost and construction time.

Key words: shallowburied fourtrack railway station tunnel, systematic anchor bolts, inequable support parameters, numerical simulation, anchor bolt axial force