Experimental Study On Flexural Behavior Of HRB400 Reinforced CF40 High Performance Steel Fiber Reinforced All-lightweight Concrete T Beam

SFRELAC has excellent properties such as light weight,high strength,heat insulation,good durability,and strong earthquake resistance.It has broad application prospects in long-span bridge structures,high-rise buildings and maritime engineering.At the same time,it is also an ecological and environment-friendly building material.With the implementation of sustainable development strategy,its advantages are more prominent.At present,the research on lightweight aggregate materials has been relatively mature,but most of the research on lightweight aggregate components are only small components,and bending is very important in the component,but the research results of its mechanical properties can not meet the new needs in the current application of SFRELAC.Therefore,it will be a subject of great theoretical significance and practical value to conduct experimental research on the mechanical properties of SFRELAC members.In this paper,five groups of steel fiber SFRELAC with h=700mm and length of 4000mm were designed by changing the volume ratio of different steel fibers.Test and data results show that:(1)SFRELAC beams are generally similar to normal fiber concrete when they are bent.The control section of concrete under bending still follows the basic assumption of plane section.(2)steel fiber has a high effect on the bending capacity of SFRELAC beams,and its bearing capacity increases as the volume ratio of steel fiber increases.(3)the development of SFRELAC beams is similar to that of RC beams in that steel fibers can increase the cracking moment of SFRELAC beams,and the average crack width of SFRELAC beams decreases with the increase of the volume ratio of steel fibers,and a calculation formula for appropriate SFRELAC beams is established.(4)under the same load level,SFRELAC beam deflection was lower than that of ordinary light aggregate concrete beam,and the deflection gradually decreased with the increase of the volume ratio of steel fiber,steel fiber can improve the stiffness of light aggregate concrete beam,and a suitable short-term stiffness formula was established.