为研究采用波纹钢新型结构进行公路隧道竖井支护设计的技术与经济可行性,首先,探讨波纹钢在隧道初期支护、加固衬砌、保温套衬以及作为通风导洞中隔墙的应用特点,明确其在隧道竖井支护中的应用可能性。然后,基于鹦哥岭隧道的工程地质条件,通过理论计算与数值模拟相结合的方法对钢波纹管结构进行力学性能验证。基于结构承载力理论开展手算校核,重点分析混凝土轴心抗压强度和土压力合力;依据荷载-结构模型原理,使用ABAQUS有限元构建考虑土体-结构相互作用的钢波纹管三维数值模型,分析模拟实际工况下的力学响应,提出基于波纹钢的竖井支护设计方案。最后,详细阐述波纹钢竖井支护的施工工艺,并对比传统设计方案,进行成本效益分析。研究结果表明: 1)波纹钢应用于隧道竖井支护具有良好的技术可行性,其构件在地层结构中安全可靠; 2)波纹钢支护造价虽比传统方案增加10%,但显著提高了结构强度和承载能力,增强了变形适应性; 3)波纹钢支护有效封堵了围岩涌水,缩短了施工周期,施工效能提升显著,具有综合经济优势。
Herein, the technical and economic feasibility of
corrugated steel support structure for highway tunnel shafts are examined.
First, the application characteristics of corrugated steel in the primary
support of tunnel, reinforcement lining, thermal insulation lining, and
partition wall of ventilation guide tunnel are discussed, clarifying the
application possibility of corrugated steel in the support of tunnel shafts.
Then, based on the engineering geological conditions of the Yinggeling tunnel,
the mechanical properties of corrugated steel structure are verified using
theoretical calculations and numerical simulations. Based on the theory of
structural bearing capacity, the manual calculation is conducted, and the axial
compressive strength of concrete and the resultant force of earth pressure are
analyzed. Additionally, based on the principle of load-structure
model, ABAQUS finite element is employed to construct a three-dimensional numerical model of corrugated steel considering soil-structure interaction. Subsequently, the mechanical response under
actual working conditions is analyzed and simulated, thus proposing a design
scheme of support of shaft using corrugated steel. Finally, the construction
technology of support using corrugated steel is described in detail, and the
cost-benefit of this approach is compared with the
traditional design scheme. The research results show the following: (1) The
corrugated steels are technically feasible in primary support of tunnel shaft,
exhibiting safe and stable state in stratum. (2) Although the cost of the
corrugated steel support is 10% higher than traditional scheme, but the structural
strength, bearing capacity, and
deformation adaptability are much higher. (3) The corrugated steels effectively
seal surrounding rock water gushing, shorten construction period, and improve
construction efficiency, exhibiting good comprehensive economic benefits.