Some Investigations on Cracking of the Tunnel in Cold Region

寒区隧道裂缝的一些调查

基本信息

批准号：
12555131
负责人：
MIKAMI Takashi
金额：
$ 6.02万
依托单位：
HOKKAIDO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2002
项目状态：
已结题

项目摘要

The project is summarized as follows :(1) Temperature can be defined from homogeneous spatial processes by means of a linear transformation, and the design temperature for tunnel heat insulator can be interpolated by Semi-Variogram using a stochastic algorithm. A comparison of the estimated design temperature and the observed temperature of actual data shows that the proposed method yields very good results.(2) The periodic changes of atmospheric temperature can be transformed to a moving mean value and narrowing amplitude due to distance from the entrance of the tunnel.(3) It is found that data mining procedure using neural network is useful for finding the cause of cracks in the tunnel lining.(4) A numerical method is developed for analyzing for the one-dimensional moving boundary problem in semi-infinite region. The method is useful for determining the depth of the frozen ground behind tunnel lining. A comparison with other solutions suggests that the proposed method provide satisfactory accuracy.(5) In order to investigate the mechanics of thermal cracking in the tunnel lining, heat transfer and stresses are determined using the two-dimensional finite element method and employing interface element for the heat insulator. A concrete model including ageing effects and time-dependent properties is adopted. It is made clear that the elastic modulus of concrete in early ages and thermal conductivity of concrete are sensitive to thermal cracking.

该项目的总结如下：（1）可以通过线性转换从均匀的空间过程来定义温度，并且可以使用随机算法通过半变量图来插值隧道热绝缘子的设计温度。比较估计的设计温度和实际数据的观察到的温度表明，所提出的方法会产生非常好的结果。（2）可以将大气温度的周期性变化转换为移动的平均值和移动的平均值和幅度狭窄，这是由于距隧道入口的距离。（3）发现，使用神经网络的数据挖掘程序可用于在the nection for in the Is n tunnel linn tunnel linn linn line linn linn linn linn。（4）。半无限区域的一维移动边界问题。该方法可用于确定隧道衬里后面冷冻地面的深度。与其他溶液的比较表明，所提出的方法提供了令人满意的精度。（5）为了研究隧道内衬中热裂纹的机制，使用二维有限元方法确定热传递和应力，并采用界面元素作为热绝缘子。采用了包括衰老效应和时间相关特性的具体模型。可以清楚地表明，早期混凝土的弹性模量和混凝土的导热率对热裂纹敏感。