The mechanized excavation of tunnels generally requires the injection of a grout material between the segmental lining and the ground. This material has an important role for the support system and governs the segmental lining loading, also because of the significant evolution of its mechanical characteristics over time. In this work, an accurate experimentation on the two-component material was conducted. Normally, hand mixing is performed in laboratory to test the mechanical performance of the two-component mix-design. In this paper an innovative instrumentation able to mix appropriately the components was used in order to obtain samples truly representative of the real site conditions. Laboratory compression tests performed on these samples allowed to accurately quantify the evolution of the strength and stiffness of the filling material during the setting time. In order to properly take into account the evolution over the time of the mechanical behaviour of the filling material and of the support system more generally, a new procedure was developed and illustrated in the work. The analysis procedure is based on the convergence-confinement method and is able to describe in some detail the reaction line of the support system during its loading. Due to the presence of the filling material, which improves its mechanical characteristics over time, the reaction line assumes a curved shape. The intersection with the tunnel convergence-confinement curve allows to determine the radial loads acting on the support system and to design the support system to ensure the stability of the tunnel. The innovative procedure was then applied to a real case of a tunnel excavated in Northern Italy, confirming the validity of the main project data adopted for segmental lining and filling material. A sensitivity analysis on the same case allowed to detect how some aspects of the support system loading have an influence, not only on the final radial load acting on the segmental lining, but also on the final stress state induced inside the filling material.

隧道的机械化开挖通常需要在分段衬砌和地面之间注入灌浆材料。这种材料对于支撑系统起着重要作用，并且控制分段衬砌的载荷，这也是由于其机械特性随时间的推移而发生的显着变化。在这项工作中，对两组分材料进行了精确的实验。通常，在实验室中进行手动混合以测试两组分混合设计的机械性能。在本文中，使用了一种能够适当混合各成分的创新仪器，以获取真正代表实际工况的样品。对这些样品进行的实验室压缩测试可以准确地量化凝固时间期间填充材料的强度和刚度的变化。为了更适当地考虑填充材料和支撑系统的机械性能随时间的变化，开发了一种新的方法并在工作中进行了说明。分析过程基于收敛约束方法，能够详细描述支撑系统在加载过程中的反应线。由于填充材料的存在，随着时间的流逝改善了其机械特性，因此反应线呈现弯曲的形状。与隧道会聚约束曲线的交点可以确定作用在支撑系统上的径向载荷，并设计支撑系统以确保隧道的稳定性。然后将创新程序应用于意大利北部开挖的隧道的实际案例，确认了分段衬砌和填充材料所采用的主要项目数据的有效性。通过对同一案例的敏感性分析，可以检测到支撑系统负载的某些方面如何产生影响，不仅对作用在分段衬里上的最终径向负载有影响，而且还影响了填充材料内部引起的最终应力状态。确认用于分段衬砌和填充材料的主要项目数据的有效性。通过对同一案例的敏感性分析，可以检测到支撑系统负载的某些方面如何产生影响，不仅对作用在分段衬里上的最终径向负载有影响，而且还影响了填充材料内部引起的最终应力状态。确认用于分段衬砌和填充材料的主要项目数据的有效性。通过对同一案例的敏感性分析，可以检测到支撑系统负载的某些方面如何产生影响，不仅对作用在分段衬里上的最终径向负载有影响，而且还影响了填充材料内部产生的最终应力状态。