陆水水利枢纽二号副坝闸墩裂缝成因分析及缺陷处理方案

Cause analysis of cracks on No.2 auxiliary dam pier of Lushui Hydropower Complex and defect treatment Scheme

陆水水利枢纽2号副坝闸墩出现斜向裂缝,对枢纽工程的安全可靠运行产生不利影响。依据《水工混凝土结构设计规范》,对闸墩进行结构强度及配筋复核计算。采用有限元计算,从受力角度进一步分析闸墩斜向裂缝产生的原因。计算结果表明:弧形工作闸门下游侧附近受闸门支座推力及温升荷载长期反复作用,加之闸门支座扇形钢筋延伸长度不满足规范要求,是导致泄洪闸闸墩部位混凝土产生斜向裂缝的主要原因。从裂缝成因、施工条件、工程造价等方面综合考虑,提出了采用化学灌浆和粘贴钢板的处理方案,有效控制了裂缝发展。研究成果可为类似工程裂缝成因分析和缺陷处理提供参考。

Diagonal cracks appeared on No.2 auxiliary dam pier of Lushui Hydropower Complex,which exerted adverse effect on the safety and reliable operation of the dam.Based on the Code for Design of Hydraulic Concrete Structures(SL191-2008),we performed the structural strength and reinforcement calculation of the pier.The finite element method was adopted to further analyze the causes of the cracks from the perspective of force action.The analysis showed that the major cause for the diagonal cracks were:the downstream side of the arc-shaped working gate was under the dual influences of thrust of gate support and the rising temperature for a long time;the extension length of the fan-shaped steel bar on the gate support does not meet the requirements.Considering the causes of cracks,construction conditions,and engineering cost,we proposed the treatment scheme of combined chemical grouting and pasting steel plate.The analysis results can provide references for identifying the crack cause and defects treatment for other similar projects.