嵌贴CFRP筋抗剪加固RC深T梁优化方法

Optimized Schemes on Shear Strengthening of Deep T-Cross-sectional RC Beams with Surface Embedded CFRP Bars

深T梁因其极限承载力主要受剪力控制,易发生脆性剪切破坏进而造成结构破坏。因此,如何掌握梁内力流分布,并采用相应的加固措施提高现役梁的抗剪承载力以减少结构垮塌就成为当前研究的热点。表层嵌贴CFRP筋加固技术因其包裹性好、整体粘结性能优、施工效率高且不增加结构自重等优势正在兴起。借鉴‘拉-压杆’模型,数值分析研究深T梁的内力流分布规律,并据此制定出简单及优化等2种加固方案,构建相对应的2组实验深T梁并实施验证性实验。比对有关深T梁在加固前后的理论分析、数值模拟及验证性实验成果中的抗剪承载力及裂缝宽度等关键参数,最终获证所选用的2种加固方案分别使得深T梁的抗剪承载力提高了45%、65%,充分说明了本文所依据的原理及制定的加固方案有效、可行,能够指导工程实际。

Due to its ultimate bearing capacity mainly controlled by the shear force,the deep T beam is prone to brittle shear failure and cause structural disaster.How to scientifically figure out the distribution of internal force flow in beams and adopt corresponding reinforcement measures to improve the shear capacity of active beams and reduce structural disasters has become a hot research topic.Surface embedded CFRP reinforcement technology is emerging as a result of its advantages of good encapsulation,excellent overall bonding performance,high construction efficiency and no increase in the weight of the structure.Based on the model of"tension and compression bar",the distribution law of internal force flow in deep T beam was studied numerically,and two reinforcement schemes,namely simple and optimized,were developed accordingly.Two groups of corresponding deep T beams were constructed and verified experiments were carried out.By comparing the key parameters such as shear capacity and crack width in the theoretical calculation,numerical simulation and confirmative experimental results before and after the reinforcement of deep T beam,the results show that the two presented reinforcement schemes increases the shear capacity of deep T beam by 45%and 65%,which fully demonstrates the feasibility of the proposed reinforcement schemes and their principle.Based on the above research results,an invention patent has been applied to complete the corresponding reinforcement theory and technology and to guide the engineering practice.