Resumen de Anti-fatigue optimization of mining dump truck frame joint with discrete design variables
XiaoKui Ma, ZhengQi Gu, ZhengTong Han, ChengJi Mi, Xingzhong Jin
Weld of mining dump truck (MDT) frame is prone to fatigue damage due to the unreasonable local structure of cavity with stiffeners. However, there are considerable limitations in the engineering implementation of both size and topology optimization of the frame. Therefore, a discrete optimization method for the structure composed of cavity with stiffeners like MDT frame joint is proposed. Considering the possible early failure, the joint with failure-prone welds is extracted from the frame as the research object. The structural stress of every node on the weld line defined by the Verity method is analyzed and the structural stress spectrum of each weld node is obtained. Then, the ground structure of the frame joint is established with every possible stiffener so the joint structure can be defined by the birth or death status of every stiffener. The constraint of joint mass is transformed into the constraint of the number of stiffeners to improve the optimization model for feasibility and efficiency. By the utilization of the multi-island genetic algorithm (MIGA) without gradient information, the anti-fatigue optimization of MDT frame joint with discrete design variables is realized. Under the premise of maintaining manufacturability, the minimum fatigue life of the welds on the optimized frame joint increases significantly while the weight of the joint is lessened.
