冻土隧道的保温隔热层参数设计新方法

目前几乎所有冻土隧道设计都会采用保温隔热层避免冻融作用发生,但是在保温隔热层的参数选取时,保温隔热效果是主要考虑的因素,而对其成本考虑较少。为了使保温隔热层既能防止冻融作用的破坏,又能节约成本,以优化理论为基础,结合扩展内点罚函数及冻土隧道特点,建立了保温隔热层的数学优化模型,期望该模型能够达到此目的。以大坂山K0+785断面和风火山隧道K0+835断面为例,验证了该数学模型不仅能用于季节性冻土隧道,而且也能用于多年冻土隧道。优化结果不但能够防止冻害发生,而且还能产生较大的经济效益。由此可见该数学优化模型及求解方法可以为冻土隧道工程中的保温隔热层参数的合理选取提供指导。

A New Method on the Parameters Design of Heat Preservation and Insulation Layer in Frozen Tunnels

The insulating layers are usually used in the frozen tunnels to avoid the occurrence of freezing and thawing currently. However, the insulating effect is the most important factor and the cost is often paid little attention. In order to prevent freeze-thaw damage and save costs a mathematical optimization model about insulating layer is built by optimization theory, extended interior penalty function and frozen characteristics and it is expected to achieve the goal. It is shown that the mathematical optimization model could be applied to seasonal frozen tunnel and permafrost tunnel method after the K0+785 section of Dabanshan tunnel and the 0+835 section of Fenghuoshan tunnel are optimized by it. In addition, the optimization results could not only prevent the frozen damage but also obtain a large amount of economic benefits. Thus it can be seen the mathematical optimization model and solution method could provide guidance for the rational selection of insulating layer parameters when the insulating layer is used in the frozen tunnels.