Experimental Research On Pressure Bearing Capacity Of Reinforced Stone Columns By Extended Section Method

As a traditional building structure,the stone structure is a form of residence often used in coastal areas of China.However,the poor integrity of stone masonry is one of the main weaknesses of stone-structured houses.In view of the lack of vertical bearing capacity in stone masonry structure,this paper adopts the method of expanding section to strengthen the masonry column,and uses reinforced concrete surface layer reinforcement method and steel mesh cement mortar surface layer reinforcement method as the research obj ect.(1)The research on domestic and foreign methods of reinforcement of stone masonry columns is searched.The related literature shows that the research on stone masonry structures in China focuses on the constitution of materials,the state of reinforced surface layer under pressure,and the failure mechanism of stone masonry components;The foreign research on stone masonry structures focuses on the mechanical properties of stone,the effect of stone masonry mortar joints,aspect ratio,and integrity on the structure.For the dry-laid laying masonry,there are few studies on the masonry columns,and the utilization factor of the materials in the calculation formula of the bearing capacity of the reinforcement members is not given.(2)Research on the reinforcement method of reinforced concrete surface layer,and three pieces of reinforced concrete surface reinforcement reinforced by masonry columns and columns were constructed to carry out vertical bearing capacity test.The effect of reinforcing ratio of longitudinal reinforcement steel reinforcement and vertical force loaded eccentricity on the reinforcement effect was studied.The test results show that the ultimate bearing capacity of the strengthened members is increased by 103.87%and 258.42%respectively compared to the unstiffened stone masonry.When the component is broken,the stressed steel bars in the reinforced surface layer undergo buckling failure.After regression analysis,this paper proposes that when the reinforced concrete surface reinforcement member axial bearing capacity,its strength of reinforced concrete and concrete should be multiplied by a reduction factor of about 0.7.(3)Research on reinforcing method of steel mesh cement mortar surface reinforcement method,making three pieces of reinforced concrete mortar surface reinforcement reinforced stone masonry column member,and carrying out vertical load carrying capacity test.The effect of reinforcing ratio of longitudinal reinforcement steel reinforcement and vertical force loaded eccentricity on the reinforcement effect was studied.The test results show that the ultimate bearing capacity of the strengthened members is increased by 43.07%and 143.52%,respectively,compared to the unstiffened stone masonry.When the component is broken,the stressed steel bars in the reinforced surface layer undergo buckling failure.After the regression analysis,this paper proposes that when the reinforcement strength of the reinforcement member of the steel mesh cement mortar is carried out in the axial direction,the reinforcing strength of the steel bar and the mortar should be multiplied by a reduction factor of about 0.5 and 0.25.(4)The finite element analysis software ABAQUS was used to analyze the parameters of the reinforced concrete surface reinforcement method.The separate model was used to establish the material rock,gaskets reinforced surface and steel mesh,and the accuracy of the finite element model was verified by comparison with the test results.The other factors affecting the bearing capacity of the post-reinforced masonry columns are verified.The results show that:increasing the strength and thickness of the reinforced surface,and increasing the number of gaskets between the stones can increase the vertical bearing capacity of the components.