柔支腿对门式起重机挠度的影响

在工程实际应用中，针对检测砝码重量不足的情况下，评估起重机结构的安全可靠性是检测中急需解决的问题.主梁挠度是起重机整机试验中最重要检测指标，因此，定量地掌握结构参数对主梁挠度的影响尤为重要.对于大跨度大吨位门式起重机，以往的解析计算都没有考虑一刚一柔支腿对主梁挠度的影响.文中针对通用大跨度大吨位门式起重机建立数学模型，在考虑主梁弯矩和支腿弯矩的耦合作用下，基于变分原理求得了门架结构主梁跨中挠度的解析解.然后设计实验模型，在WEW-600B型试验机上进行实验.实验数据表明，门架结构挠度的解析解较原有的计算方法，计算精度有很大提高，为门架结构的设计和检验提供了理论依据.

The Effect of Rigid-soft Legs on Mid-span Deflection in Gantry Cranes

In practical application, when the test weight is insufficient, it is urgent to solve the safety and reliability problems of crane structure. The deflection value is one of the key inspection indices of crane girder under rated loading in overall test. Therefore, it is very important that the influence of structure parameters on the mid-span deflection is quantified. For large-span and heavy-duty gantry cranes, the effect of rigid-soft legs on mid-span deflection was not considered in the past. So a mathematical model was established for universal large-span and heavy-duty gantry cranes. Considering the coupling effect of the bending moment of girder and legs, the analytical solution was derived and obtained on the basis of the variational principle. Then, the experimental model was designed and experiments were performed on the WEW-600B type testing machine. The experiment data show that the analytical solution of the gantry-frame structure deflection is more accurate than the pre-existing calculation method, which provides an analytical tool for the design and inspection of gantry structures.