The Research On Interfacial Bond Behavior Of RC Structure Reinforced By HPF And Construction Technology Of The HPF

High performance ferrocement (HPF) technology is a new method to reinforce the reinforced concrete(RC) structure, by which a kind of high performance composite mortar and reinforcing steel bar mesh are used to repairing and strengthening the RC structure. The latest study proves that HPF technology is an efficient method to reinforce RC structure, which can obviously increase the load-bearing capacity, stiffness, crack-resisting behavior, so it will be applied widely in construction reinforcement industry. The bonding quality of new repairing layer to old concrete interface is the key to this kind of reinforcement work. Therefore, the research on bonding quality of adhesion between HPF and concrete has important theoretical meanings and profound significance. The research is carried out by the support of Hunan Science and Technology Department and Changsha Science and Technology Bureau.The main archivements of this dissertation are described as follows:Firstly the research is made on splitting tensile behavior of adhesion between high performance composite mortar and concrete. The splitting section arises in the adhesive section and the splitting destruction shape is summarized when the adhesive section is processed with three methods. Prominent property analysis of influential factors of splitting tensile strength shows cement-mortar strength is more prominent than the process of adhesion section and concrete strength is less. The test results show the splitting tensile strength increases with the raise of concrete strength and high performance composite mortar strength, and proper surface roughness of old concrete contributes to the adhesive behavior of high performance composite mortar and concrete. The model of the relationship between the splitting tensile strength and composite mortar strength is set up according to the test results.Secondly the research is made on tensile behavior of high performance cement-mortar to concrete through core-drilling and pull-stripping test. The destruction shape arises in the adhesive section in the test when the adhesive section is processed with three methods, the proper roughness of adhesion section improves the tensile strength. Prominent property analysis of influential factors of tensile strength shows interface cementitious agent is more prominent than composite mortar strength and concrete strength is less. The test results show the tensile strength increases with the raise of concrete strength and high performance cement-mortar strength. The mechanism of interface cementitious agent and high performance composite mortar to the tensile behavior is analyzed with details.Thirdly the shear experiment is done on the RC blocks reinforced by HPF, which includes testing of 10 blocks strengthened with pins and 3 control specimens without pins.It issues of the pin's diameter, strength and amount to the bonding behavior. The result of the experiment shows that the pin benefits to improve the bonding quality and ductility. The three chosen factors of the pin influence the bonding behavior of the RC structure reinforced by HPF, and primary and secondary relations between these factors are determined using the mathematical mode in grey degree of incidence in grey theory. On the basis, some advices are presented to improve the bonding quality.Finally based on the latest and related codes and the successful works reinforce by HPF, the thesis provides the proper construction workmanship of the HPF technology besides the system method of controlling and inspecting the construction quality, which contribute to the enhancement of construction quality and the wide use of the HPF technology.