独立式石箍窑洞地震模拟振动台试验及数值模拟

Shaking table test and numerical simulation for free-standing stone cave dwelling

以山西省静乐县的某独立式石箍窑洞为原型,制作1/4缩尺的三跨试验模型,对其进行了地震模拟振动台试验,分析了地震作用下窑洞模型的破坏过程及破坏形态。在试验研究基础上,采用ABAQUS软件建立独立式石箍窑洞的有限元模型,将模拟得到的动力特性、动力响应和地震损伤结果与试验结果进行了对比分析,验证了有限元模型的合理性,进而基于对原型结构的有限元模拟,分析了覆土厚度、拱跨数和拱矢跨比对窑洞模型受力性能的影响。结果表明:独立式石箍窑洞在地震作用下主要发生砂浆灰缝开裂破坏,开裂最严重的部位为洞口拱顶和侧墙与背墙的连接处;有限元模拟结果与试验结果吻合较好,能够较好地反映地震作用下窑洞模型的受力性能;窑洞模型的纵墙刚度大于横墙,加速度和位移响应随输入峰值加速度的增大不断增大;随着覆土厚度变薄和拱矢跨比减小,窑洞模型的抗震性能增强,但拱跨数对窑洞模型的抗震性能影响较小。

Taking a free-standing stone cave dwelling in Jingle county,Shanxi province as the prototype,the 1/4 scale test model with three spans was manufactured and carried out by shaking table test.The failure process and failure pattern of cave dwelling un⁃der earthquake action were analyzed.Based on the test,the finite element analysis(FEA)model of free-standing stone cave dwell⁃ing was established by using ABAQUS.The dynamic characteristic,dynamic response and seismic damage,which were obtained by simulation,were compared with test results to verify the rationality of the FEA model.And then the FEA models of prototype structures were established,and the influence of soil thickness,number of arch spans and rise span ratio on the mechanical perfor⁃mance of cave dwelling was analyzed.The results showed that the main failure of free-standing stone cave dwelling under earth⁃quake action was the cracking of mortar joint,and the most serious cracking failure occurred at the vaults of cave dwelling entrance and the connection between side walls and back wall.The simulation results agreed well with the test results,which can better re⁃flect the mechanical performance of cave dwelling under earthquake action.The stiffness of longitudinal wall was larger than that of horizontal wall.The acceleration and displacement responses of cave dwelling increased with the increasing of input peak accelera⁃tion.As the decreasing of soil thickness and rise span ratio,the seismic performance of cave dwelling could be improved,but the in⁃fluence of number of arch spans was insignificant.