论文部分内容阅读
隧道支护结构开裂现象是工程界普遍关注的课题,根据工程实例,采用现场监控量测资料阐述了明洞与支护开裂的位置,结合隧道的周边位移和拱顶下沉随时间和施工进度的变化趋势,得出不良地质情况和严重偏压是明洞与支护开裂的主要原因。依据现场处理措施得出施作仰拱和对隧道埋深较浅侧进行小导管注浆加固能有效地抑制支护结构裂纹发展。采用变分方法与Bishop条分法相结合定性分析得出偏压隧道薄弱部位及产生偏压的原因。通过数值分析获得明洞的第一主应力分布状态,解释裂缝出现于拱顶与偏压侧拱肩之间的原因;数值分析获得的隧道周边位移和拱顶下沉与现场监测结果具有相同的发展趋势;断面离隧道洞口越近,周边位移向外扩展值越大,表明洞口处为隧道最薄弱部位。
Cracking phenomenon of tunnel support structure is a common concern in engineering. According to engineering examples, the location of open hole and support cracking is explained by on-site monitoring measurement data. Combined with the surrounding displacement of tunnel and the settlement of dome with time and construction progress The trend of change, come to bad geological conditions and serious bias is the main reason for Myeong-dong and support cracking. According to the on-site treatment measures, it is concluded that the use of inverted arch and the shallow conduit on the shallow side of the tunnel for grouting reinforcement can effectively suppress the crack growth in the support structure. The variational method and the Bishop method are used to analyze the weak parts of the tunnel and the causes of the bias. The distribution of the first principal stress of Myeong-dong is obtained by numerical analysis, and the reasons for the cracks appearing between the vault and the side arch are explained. The numerical results show that the circumferential displacement of the tunnel and the vault settlement have the same Development trend; the cross section of the tunnel is closer to the tunnel entrance, the larger the value of the outward displacement of the surrounding displacement is, indicating that the tunnel entrance is the weakest part of the tunnel.