Strengthening of concrete members using steel plates is a well known and an extensively applied technique. Fibre reinforced polymer (FRP) composites have been established as an alternative method for rehabilitation and strengthening of concrete structures. In this project, reinforced concrete (RC) beams had been externally strengthened with glass fibre reinforced polymer (GFRP) sheets. In order to investigate the load capacity and member failure by altering the number of bonded layers (two or four), a series of static tests was carried out. Results show that, by the use of U-jackets, the deflection is reduced and the load capacity of the member is increased up to four times compared with the conventional RC beams. Two failure modes were observed; failures of the GFRP close to the mid-span area (when 2-layers GFRP had been used) and a shear failure between the GFRP sheet and the concrete surface at the end of the beams (when 4-layers were used).

研究了配有工字钢的型钢混凝土柱一普通钢筋混凝土梁及配有工字钢的型钢凝土柱及型钢混凝土梁节点受力性能。介绍了三种节点共六个试件承受低周反复荷载的试验，第一种节点是型钢混凝土柱与普通钢筋混凝土梁节点，按发生节点核心区剪切破坏设计；第二种是型钢混凝土梁柱节点，按发生节点核心区剪切破坏设计；第三种是型钢混凝土梁柱节点，按发生梁铰型破坏设计，每组试件各两个试验结果表明，发生梁铰型破坏的型钢混凝土粱柱节点耗能性能最好．

对型钢与混凝土的粘结性能进行了试验研究。分析了型钢与混凝土的粘结机理, 探讨了混凝土强度等级等因素对粘结性能的影响, 给出了粘结应力分布模式, 并建立了粘结极限荷载的计算公式, 结论对工程实际有一定指导意义

More and more isolators are widely used all over the world. For a structure with isolator between base and super-structure, it is suitable to take only the first-mode in consideration for the super-structure, the structure become a 2-DOF system, and its damping and stiffness matrices are non-symmetrical. The equation of motion cannot be decoupled by the mode-superposition method. A complex-mode method is proposed and analytic expressions are obtained under earthquake excitation in the paper. Base on above analytic expressions suggested by authors, an isolator index β(the ratio of the standard deviation of the displacements at the top of super-structure), an optimal design process and some useful data are achieved. All of these are meaningful in practice projects.

The flocculation procea can be described by flocculation kinetics．A silica pa rticle SuY,pensi(in was coag ulated with inorganic coagulants，and the flocculation kinetics was studled through easuring and anaIyzing the vari-ation of particle number during the floceuiation process The resuIts show that the flocculation kinetics；Ire lnfIu enced by the flocculation time. coagulant dosages and coagulant kinds，erc The flocculation process follows the first-order reaction in the beginning phase for about 10min; within the later time the flocculation process does NOT foBow the first-order reaction any nlore．With increasing coagulant dosage the floeculation rate inerease，and with the larger dosages the flocculation process goes on rapidly，deviating from the first-order reaction．The effective co-agulants Can improve the flocculation rate．