预应力混凝土管桩后注浆器的研制与应用

Development and application of after grouting device for prestressed concrete pipe pile

针对目前预应力混凝土管桩后注浆器仅能单独实现桩底或桩侧注浆、结构形式不合理等问题,进行了后注浆器的设计与优化,并将研制的后注浆器应用于工程。设计了3种结构形式的注浆器,通过分析将要达到的注浆效果和结构形式,优选结构一进行优化。利用ANSYS有限元分析软件,优化了结构一的配筋率,验算了注浆通道的强度和刚度。通过现场应用表明,研制的注浆器性能稳定可靠,能够显著提高单桩竖向抗压极限承载力,对提高管桩性价比具有很好的效果。相比于其他注浆器,该注浆器首次实现由压力控制桩底—桩侧联合注浆,能够防止浆液回流,确保桩底、桩侧的注浆量。

To solve the problems that the after grouting devices could only achieve pile bottom grouting or pile side grouting and the structure was irrational,the design and optimization of after grouting device were put forth,and then were used in engineering. 3 kinds of after grouting devices were designed. Structure one was chosen to be optimized by analyzing the effect of grouting and the structure of the form. Reinforcement ratio of structure one was optimized by using finite elements analysis software ANSYS. In addition,the strength and rigidity of the injection channel were checked by the same way. The field application showed that the device performance was stable and reliable. The ultimate vertical bearing capacity of a single pile could be significantly improved. This device also had good effects on improving the performance price ratio of the pile. Compared to other after grouting devices,this device could realize the control of pile end and pile side grouting by pressure control for the first time,which could prevent slurry return and ensure pile end and pile side grouting quantity.