吸力式桶体基础结构钢筋骨架失稳研究

Instability study on reinforcement skeleton of suction bucket foundation structure

连云港徐圩防波堤工程吸力式桶体基础(SBF)为大尺寸混凝土薄壁结构,施工中钢筋骨架容易发生失稳。基于特征值屈曲理论和有限单元法,研究钢筋骨架高度、边界约束条件、钢筋直径等因素对骨架稳定性的影响。计算发现,底部约束和侧向支撑可以显著提高稳定性;仅增加竖向钢筋直径不能保证稳定性提高;采用边界类型IV得到的稳定系数满足规范要求。提出钢筋骨架防失稳施工方案,实际工程验证了其可行性。

Owing to large-size dimensions of the Suction Bucket Foundation（ SBF） applied by Xuwei breakwater in Lianyungang, the reinforcement skeleton tends to lose stability during construction. Based on the eigenvalue buckling theory and finite element method, we studied the influence of the reinforcement skeleton＇ height, the boundary constraint, and the diameter of bar on the stability of reinforcement skeleton. It is found that, using the bottom boundary constraint and the lateral support can greatly improve stability; the increase of bar＇s diameter cannot guarantee more stable; the stability coefficient calculated according to boundary condition IV can meet requirement of the national standard. Additionally, construction method is presented to ensure the stability of the reinforcement skeleton, which has been proved effectively in practice.