预应力先张法加固钢筋混凝土框架梁的方法

根据粘钢加固和碳纤维加固时存在二次受力,往往由于变形和裂缝过大使得加固材料不能发挥作用,体外预应力加固与原结构协同工作能力差且不便装修等问题,提出了采用先张法加固钢筋混凝土框架梁的一种新方法.这种方法的主要思路是:在柱内植锚件,通过张拉加固角钢或钢板使加固钢达到与梁内钢筋几乎同步的应力状态,然后粘结加固钢,当粘结达到设计强度后放松加固钢,使锚接力变为加固钢板与梁受拉边沿的粘接力,这样梁二次受力后即可实现梁内钢筋与加固钢板同步工作.同时,给出了这种方法的计算理论和施工技术,并在加固工程中进行了应用.

Strengthening method for R.C. framed beams with prestressed pretension

Because there is secondary force action with the strengthening methods of both steel-adhesion and carbon fiber consolidation, the strengthening materials cannot well function due to excessive deformation or cracks and, in addition, the coordinative working ability of external prestressed strengthening and the original structure is poor and the installation and repair are also inconvenient. Therefore, a new method is advanced to be adopted for strengthening of R.C. framed beams with pretension. The idea of this method lies in that as follows: An anchor block is embedded into the column, and the strengthening steel and the reinforcing bar within the beam are made to work under cynchronous stress by means of drawing the strengthening steel angle or plate. Then, the strengthening steel is adhered and, when the adhesion has consolidated to be of designed strength, the strengthening steel is loosened, making the anchoring force turn to be the adhesive between the strengthening plate and tension side of the beam so that, when the beam is subjected to secondary force action, the reinforcing bar within beam and strengthening steel plate can work cynchronously. The theoretical computation and constructional technique related to this method is also presented and applied to the strengthening construction.