考虑围岩破坏条件时优化小净距隧道最小净距的研究

Study on Super-small Interval in Optimized Small Interval Tunnel with Surrounding Rock Damage

小净距隧道由于不受地形条件以及总体线路线型的限制,较连拱隧道有施工工艺简单、造价较低等优点,越来越受到青睐。用有限单元法对小净距隧道不同中柱厚度进行数值模拟,通过格里菲斯破坏判据以及德鲁克-普拉格判据,拟合出最大拉应力及各判据屈服函数与净距的拟合曲线,在保证其稳定的基础上,对小净距隧道最合理净距做出分析。

Construction technology of small internal tunnel is more favorable because of its simple and economy than double-arched tunnel without limitation on topographical condition and line type. Numerical simulation was made on the thickness of mid-pillars in small internal tunnel with finite element method; fitting curve of maximum tensile stress, yield function criteria and small interval was obtained through Griffith damage criteria and Drucker - Prager criteria. And analysis was made on most reasonable interval of small interval tunnel.