基于自适应最小二乘法的混凝土楔入劈拉试件最大荷载与裂缝扩展的优化设计

摘要

A mathematical model of maximum load and crack propagation in the concrete wedge-splitting specimens was proposed.This model based on least square principle and model reliability was verified by cross validation method.Crack length was proved more sensi-tive in the fracture process than crack-mouth opening displacement and initial crack-mouth opening displacement was ignored in this study. Compared with the fracture experimental results,the root mean square accuracy of the optimal design is 93.9%.Thus the optimal function can be used to monitor specimens security and design maximum load.%以混凝土楔入劈拉试件为研究对象，运用最小二乘原理，建立了最大荷载与裂缝扩展之间的数学模型，并通过交叉检验方法验证了模型的可靠性。研究结果表明：裂缝扩展长度的变化远比裂缝口张开位移的变化对试件的破坏更敏感，初始裂缝口张开位移的影响可以忽略不计。与断裂试验的实测结果相比较，本模型均方根精度达到93.9%。利用该模型，可以监测构件安全并对最大荷载进行优化设计。