对水工钢闸门主梁高度的确定多以经验公式为主,理论不完善,未全面考虑截面形式与支座位置对梁高影响的问题,依据现行钢闸门设计规范,以满足强度、刚度、稳定性和几何构造要求为约束条件,以主梁和竖向隔板总用钢量最小为目标函数,分别建立单轴、双轴对称截面下的简支式和双悬臂式主梁梁高的优化模型。采用半解析法推导出简支式和双悬臂式主梁的最优梁高理论公式。通过与已建工程对比,结果表明:推导的最优梁高公式计算的梁高均与实际工程中的梁高接近,且公式有进一步优化的空间;通过减小隔板高厚比与主梁腹板高厚比可达到降低梁高的目的。该理论公式一方面可应用于工程实践,另一方面也可为完善规范提供理论基础。

At present, there are several problems in determining the height of main beam in hydraulic steel gate, including a large number of empirical formulas, imperfect theories, and ignorance of influences of section form and support position. According to design code of steel gate, with requirements of strength, stiffness, stability and geometric structure as constraint conditions, we take minimum steel amount of main beams and vertical baffles as objective function, and establish optimization models for beam height of simple support and double cantilever’s girder under conditions of uniaxial and biaxial symmetrical sections. Theoretical formulas of optimal girder height are derived by semi-analytical methods. Through comparing with built projects, we find that girder heights calculated by the theoretical formulas in this paper are close to those in practical projects, which still can be optimized. Furthermore, we can decrease beam height through reducing height-thickness ratios of partition and web of main beam. The theoretical formulas can be applied to engineering practice, and also provide a theoretical basis for improving specification.