铁路隧道混凝土衬砌爆破振动安全判据

Blasting vibration safety criterion of railway tunnel concrete lining

根据应力波理论,依照极限拉应力准则、极限剪应力准则及莫尔判据,对爆炸应力波体波对隧道衬砌结构的影响进行研究,确定基于隧道衬砌结构安全的爆破振动速度判据模型。结合紧邻隧道上方的土石方开挖爆破工程实际,对爆破振动速度判据进行求解。研究结果表明:爆破应力波体波对隧道混凝土衬砌结构破坏效应中P波占主导地位,爆破振动作用下隧道结构首先产生拉伸破坏,隧道衬砌爆破振动速度安全判据为14.51 cm/s。研究结果与爆破安全规程一致,为隧道结构安全标准的确定提供了科学依据。

According to stress wave theory, ultimate tensile stress criterion, ultimate tensile stress criterion and Mohr＇s criterion, the influences of blasting stress body-wave on tunnel concrete lining were studied, and the model of blasting vibration velocity criterion which is based on the safety of tunnel lining was established. Through the excavation blasting project adjacent to tunnel top, the blasting vibration velocity criterion was solved. The results indicate that the damage effect of blasting stress body-wave on tunnel concrete lining is mainly caused by P-wave; the lining is firstly produce tensile damage under the action of blasting vibration; the blasting vibration safety criterion of tunnel lining is 14.51 crn/s. The results are consistent with the safety regulations for blasting and provide scientific support for establishing the safety standard ofttmnel structure.