水利水电技术（中英文）

为有效改善水轮机蜗壳外围混凝土的应力和变形防止混凝土开裂以及机组基础板和座环上环板处的变形防止机组运行时产生过大的振动,丰满水电站重建工程厂房水轮机蜗壳弹性垫层采用了性能更为优越的天然软木技术方案。本文应用有限元法从蜗壳及其外包混凝土应力应变的角度研究了弹性垫层铺设方式、浇筑厚度对弹性垫层的影响,并对垫层材料的厚度和弹性模量进行优化计算。研究选用的最佳方案为:弹性垫层材料采用聚氨酯软木,厚度为2 cm,环向从距机坑里衬1.0 m处到蜗壳腰线下15°,平面范围从蜗壳进口处开始铺设至蜗壳270°,位于边缘的单位垫层材料厚度向外渐变为1 cm厚。机组运行试验测试的结果表明,弹性垫层的优化计算很成功,确保了机组和厂房的稳定运行。

In order to effectively improve the stress and deformation of the concrete around the hydro-turbine spiral case to prevent concrete cracking as well as the deformations at the foundation slab and the upper-ring plate of the seat ring of the hydropower unit for avoiding excessive vibration during the operation of the hydro-turbine unit, a technical scheme of the natural cork wood with more superior performance is adopted for the elastic cushion of the hydro-turbine spiral case in the powerhouse for the reconstruction project of Fengman Hydropower Station. The effects from the cushion laying mode and the concrete placing thickness on the elastic cushion are studied with finite element method from the aspects of the stress-strain of the spiral case and its encased concrete, while the optimal calculations of the thickness and the elastic modulus of the cushion material are carried out as well. The optimal selected scheme is that the polyurethane cork is adopted as the elastic cushion material with the thickness of 2 cm and the circumferential direction from 1.0 m away from the inner lining of the turbine pit to 15° below the spiral case waistline, of which the laying plane range is from the inlet of the spiral case to 270° of the spiral case, while the thickness of the unit cushion material at the edge gradually changes toward to 1 cm. The testing of the experimental operation of the hydropower unit shows that the optimization calculation of the elastic cushion is quite successful, thus the stable operations of the hydropower unit and the power house are ensured.