Experimental Research On Flexural Performance Of The RC Beams Strengthened With HPF

High performance ferrocement (HPF) technology is a new method to reinforcethe concrete structure and masonry structure. Depending on the fine properties of thematerials and the fine cohesion of the boundary agent, both the ferrocement layerand the original bodies work harmoniously as a whole. In order to put this methodinto practice, research team was set up in civil engineering department of HunanUniversity, which has taken on several research projects in this field. By means oftest and theoretical research on the full-scale beams under secondary load, this thesiswill make valuable contributions to the past achievements, and provide full andaccurate experiments and theory to practice projects and the compilation of《Technical Specification for Strengthening Concrete Structure with FerrocementMotor》of China Association for Engineering Construction Standardization.Firstly, based on the test of 4 full-scale beams, the influence on strengthenedbeams of the ultimate capacity, strain of steel, concrete and ferrocement are studied,according to the varieties of the first load. Formulas are proposed for thestrengthened beams about ultimate capacity based on the test and theoreticalresearch.Based on the crack and deflection data of 4 control beams and 10 strengthenedbeams, the varieties of tendency of crack and stiffness are analyzed. Formulas areproposed for the interval and width of cracks and stiffness of section, and the testvalues and the formula values are compared.Analysis the yield and ultimate capacities in the form of analytic formula,including the affects of aspect steels. Nonlinear finite element methods is employedto simulate the process of the loading test, in order to testify the effectivity ofstrengthening method ,and the test values are compared with the results of model.Lastly, the construction technology and methods for the quality control areproposed. The application of formulas is illustrated through a project example, forthe sake of the spread of this technology applying in practice project.