基于回归正交试验的隧道支护刚度影响因素分析

Analysis of Factors Influencing the Stiffness of Tunnel Support Based on Regression Orthogonal Test

摘要:

通过正交试验设计与多元线性回归的方法建立回归模型,分析不同支护刚度影响因素的敏感性和对支护刚度起到的利弊作用,得到关于支护刚度的一次回归方程,通过调整支护参数,计算并优化隧道支护刚度。针对喷混凝土厚度、喷混凝土强度、长锚杆长度、锚杆环向间距、锚杆纵向间距、钢架纵向间距对支护刚度的影响,采用L₂₅(5⁶)正交表展开一次回归正交试验,获得各参数的常数和各项偏相关系数,构建多元线性回归方程,开展极差分析和方差分析,运用SPSS软件对试验结果进行分析,并将剩余的支护刚度影响因素代入回归方程中进行验证分析。研究结果表明:该多元线性回归分析模型的预测精度较高,平均相对误差为1.14%,因素喷混凝土强度、喷混凝土厚度水平的显著性参数F值大于F_0.001,对支护刚度起到决定性作用;钢拱架的纵向间距的F值大于F_0.025,其对支护刚度影响较为显著;锚杆的环向间距、锚杆的纵向间距的F值大于F_0.1,这两个因素对支护刚度的影响一般显著;长锚杆的长度对支护刚度的值影响不显著。

Abstract:

A regression model was established through orthogonal experimental design and multiple li-near regression methods to analyze the sensitivity of different support stiffness influencing factors and their advantages and disadvantages in terms of supporting stiffness. A first-order regression equation regarding the supporting stiffness was obtained. By adjusting the supporting parameters, the tunnel supporting stiffness was calculated and optimized. Regarding the influence of sprayed concrete thickness, sprayed concrete strength, long anchor rod length, anchor rod circumferential spacing, anchor rod longitudinal spacing, and steel frame longitudinal spacing on supporting stiffness, a first-order orthogonal regression experiment was conducted using the L25(56) orthogonal table, and the constant values of each parameter and the partial correlation coefficients were obtained. A multiple linear regression equation was constructed. Through range analysis and variance analysis, the test results were analyzed using SPSS software, and the remaining influencing factors of supporting stiffness were substituted into the regression equation for verification and analysis. The research results show that the prediction accuracy of this multiple linear regression analysis model is high, with an average relative error of 1.14%. The significant parameters F values of factors such as sprayed concrete strength and sprayed concrete thickness level are greater than F0.001, which play a decisive role in supporting stiffness; the F value of the longitudinal spacing of the steel arch frame is greater than F0.025, and its influence on supporting stiffness is relatively significant; the F values of the circumferential spacing and longitudinal spacing of the anchor rod are greater than F0.1, and these two factors have a generally significant impact on supporting stiffness; the length of the long anchor rod has no significant influence on the value of supporting stiffness.