某梁结构静动联合加载疲劳研究试验件设计与分析

目的解决工程结构在交变静载荷和动载荷联合作用下的疲劳寿命预估难题。方法拟设计一梁结构试验件,方便施加静力与动载荷,并具有合适的疲劳寿命,用于静动联合加载下疲劳寿命预估研究。并采用名义应力法计算出静载荷作用下结构的寿命,采用频域法计算动载荷单独作用下结构的寿命,再以线性损伤累积理论为基础,以载荷块为单位来计算静动载荷联合加载下的寿命。结果初步给出试验载荷,得到静动载荷联合加载下危险点的寿命为1225 s。试件在1 h之内失效,满足设计要求。结论通过该方法,可以用来校核试件的实际寿命,以设计试件。

Design and Analysis of Test Pieces for Static and Dynamic Combined Fatigue of a Beam Structure

Objective To solve the difficult problem of estimating fatigue life of engineering structure under joint action of alternating static and dynamic loads. Methods A beam structure test piece was designed to facilitate the application of static and dynamic loads, and have a suitable fatigue life for fatigue life prediction under static and joint load. The nominal stress method was used to calculate the life of the structure under static load. The frequency domain method was used to calculate the life of the structure under dynamic load alone. Based on the linear damage accumulation theory, the static load combined load was calculated in units of the load block. Results The test load was given initially. The service life of static and dynamic load under combined loading dangerous point of was 1225 s. Specimen failure was within 1 h, and met the design requirements. Conclusion The method can be used to check the actual life of the specimens, in order to design specimen.