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保压蜗壳的计算方法在很大程度上影响了结果的精度和对结构受力特性的判断。为深入了解结构的受力特性。本文从施工流程出发,考虑保压缝隙的非均匀性和接触关系,实现了保压蜗壳的施工过程全仿真,并通过算例和理论分析,验证了算法(SUA)对保压缝隙模拟的有效性和准确性。该算法应用于糯扎渡水电站保压蜗壳的施工过程模拟,研究了非均匀保压缝隙的形成机理和接触界面的接触性态,并对外围混凝土应力做了细致分析。结果表明,初始保压缝隙具有非均匀和局部非张开特性,其主要导致原因是结构的非对称性,因此钢蜗壳与外围混凝土之间正好即无缝隙也不传力的理想状态不可能存在。座环上环板、机墩根部和蜗壳进口端腰部混凝土拉应力较大,是裂缝萌生的危险区域。此外,应力对比分析表明,简化算法和仿真算法应力分布规律基本一致,简化算法应力偏小,对结构配筋不利,仿真算法更加符合实际情况。两种算法混凝土环向应力在蜗壳腰部和底部吻合度较高,蜗壳顶部误差次之(个别地方误差达80%),而在座环上、下环板附近相差甚远。
The method of calculating the pressure-holding volute greatly affects the accuracy of the results and the judgment of the mechanical properties of the structure. In-depth understanding of the structure of the force characteristics. In this paper, starting from the construction process, considering the non-uniformity and contact relationship of the pressure-retaining gap, the full simulation of the construction process of the pressure-retaining scroll was realized. The numerical simulation and the theoretical analysis proved that the algorithm (SUA) Validity and accuracy. This algorithm is applied to simulate the construction process of the pressure retaining scroll of Nuozhadu Hydropower Station. The formation mechanism of non-uniform pressure-retaining gap and the contact state of the contact interface are studied. The stress of the surrounding concrete is analyzed in detail. The results show that the initial pressure-retaining gap has non-uniform and local non-open characteristics, which is mainly due to the asymmetry of the structure. Therefore, it is impossible for the ideal state between the steel volute and the surrounding concrete to have no gap and no force exist. Ring ring on the seat ring, the root of the pier and the entrance of the volute waist concrete tensile stress larger, is the danger of crack initiation zone. In addition, the stress contrast analysis shows that the stress distribution laws of the simplified algorithm and the simulation algorithm are basically the same, and the stress of the simplified algorithm is small, which is unfavorable to the structural reinforcement. The simulation algorithm is more in line with the actual situation. The hoop stress of the two methods is higher at the waist and the bottom of the volute, and the error of the top of the volute is the second (with an error of 80% in some places). However, there is a big gap between the ring and the lower ring plate.