浅埋偏压小净距隧道加速度响应规律试验与数值模拟研究

Tests and numerical simulation for acceleration response laws of a shallow buried small spacing tunnel with asymmetrical pressure

为了获得浅埋偏压小净距隧道在地震作用下的加速度响应规律,采用振动台试验与数值模拟相结合的方法,以双向大瑞波(DR-XZ)作为加载波,研究了在不同加速度激振峰值作用下浅埋偏压小净距隧道的加速度响应规律,探讨了非偏压与偏压对浅埋小净距隧道加速度响应的影响。研究结果表明:在双向加载波水平方向上隧道的右半拱加速度响应较为强烈,竖直方向上拱顶与拱脚处加速度响应较为强烈;相对比隧道在加载波的水平方向上加速度响应,竖直方向上隧道加速度响应较为剧烈;地震波的激振方向对隧道加速度响应有较大的影响;隧道测点加速度响应变化趋势受上覆岩层的厚度、中岩柱及岩质边坡等因素影响;振动台试验值与数值模拟值之间的误差在合理的范围内,且两者变化趋势较为相似,验证了振动台试验的合理性与数值模拟结果的可靠性;相对于偏压隧道,非偏压隧道的加速度响应规律性较强,偏压对隧道加速度响应的影响作用较强。

In order to obtain dynamic response laws of a shallow buried small spacing tunnel with asymmetrical pressure under earthquake action,the combination method of shaking table tests and numerical simulation was used to study acceleration response laws of the tunnel under the acceleration excitation of the bi-direction Da Rui wave（ DR-XZ）with different peaks. The effects of asymmetrical pressure and symmetrical one on the acceleration response of the shallowburied small spacing tunnel were explored. The results showed that in the horizontal direction of the bi-direction loading wave,the acceleration response of the right half arch of the tunnel is stronger; in the vertical direction of the load wave,the acceleration response of the arch top and arch foot is more severe; compared with the acceleration response of the tunnel in the horizontal direction of the bi-direction loading wave,its acceleration response in the vertical direction is more severe; the excitation direction of seismic wave has a bigger influence on the acceleration response of the tunnel; the tunnel acceleration response change trend is affected by the factors of overburden thickness,middle rock pillar,rock slope and so on; the errors between shaking table test data and numerical simulation ones are in a reasonable range,both data change trends are similar,the rationality of shaking table test data and the reliability of numerical simulation ones were verified; compared with a tunnel with an asymmetrical pressure,the regularity of acceleration responses of a tunnel with a symmetrical pressure is more obvious,the asymmetrical pressure has a stronger effect on tunnel＇s acceleration responses.