Flexural Behavior Of RPC Material And Composite Beams

Reactive powder concrete(RPC)is a new type of composite material with good compressive,bending,crack resistance and durability.In modern engineering,due to the increasing progress of science and technology,ordinary concrete strength has been unable to meet the requirements of modern,beautiful and durable buildings.Therefore,the use of reactive powder concrete(RPC),which has good mechanical properties,has been put on the agenda for building construction and use,and scholars at home and abroad have also made some research on RPC.At the same time,compared with the traditional steel structure and concrete structure,the new composite structure has been widely used by many researchers because of its excellent mechanical properties.In the bridge system,the steel-concrete composite beam has the characteristics of high bearing capacity,high stiffness and low cost.It can give full play to the mechanical properties of steel beam and concrete and make its structure use reasonably.Therefore,both at home and abroad.Scholars are also steadily carrying out research on the mechanical properties of steelconcrete composite beams.It can be seen from the above that both reactive powder concrete and composite beams have superior mechanical properties,so applying the mechanical properties of reactive powder concrete to steel-concrete composite beams can give full play to the material characteristics and further improve the performance of components.At the same time,most of the traditional shear connectors are studs,and the latest Twin-PBL shear connectors at home and abroad have more advantages.The application of Twin-PBL shear connectors in Steel-Reactive powder concrete composite beams can be a research direction because of its strong shear resistance.To sum up,the main research contents of this paper are as follows:(1)Measure the compressive strength and flexural strength of reactive powder concrete.(2)Through a single variable test,the effects of water-binder ratio,fly ash,silica fume and aggregate ratio on the compressive strength and flexural strength of reactive powder concrete were analyzed,and RPC with better physical and mechanical properties was obtained.(3)Through the experimental study of three kinds of steel reactive powder concrete composite beams,the crack development and failure process of studs,Twin-PBL shear connectors,single web and double web composite beams are studied.The load-deflection curve,end load-slip curve and load-strain curve of composite beams along the height of cross section are obtained.(4)The test results of composite beams are analyzed.Based on the test data and reasonable mechanical assumptions,the bending capacity of Steel-Reactive powder concrete composite beams is calculated and compared with the test results,which is in good agreement.