Experimental Study On RC Beams Reinforced With Embedded Pre-stressed Fiber Mesh

TRM(Textile Reinforced Motar)reinforcement technology is a reinforcement form with fiber mesh and high-strength mortar as the basic material.In this paper,based on the model test,the pre-stressed TRM reinforced concrete structure was studied aiming at the low strength utilization rate of TRM.Firstly,the optimal failure mode was discussed with the reinforcement quantity and the pre-stress level as the variables,and then,combined with the model test,the short-term and long-term pre-stressed TRM stress loss was measured.Furthermore,the test of 4 pre-stressed TRM reinforced positive cross-section model beam was completed,and the parameters affecting the reinforcement effect were studied to explore the optimal method of pre-stress level determination.Finally,the numerical simulation analysis of the test beam was carried out.Through the above research,the following conclusions are obtained:(1)The main factors causing the pre-stress loss are: deformation of the active reinforcement system,slippage of the fiber in the anchorage,stress relaxation of the fiber,shrinkage and creep of the concrete,curing speed of the mortar,loss of the device such as disassembling the sensor.Summarizing the pre-stress loss rate of the reinforcement method at each stage,this paper finally concluded that the pre-stress loss rate of the reinforcement method is 13.5%-14.1%,and mainly occurs in the tensile stages;(2)The reinforcement method of this paper can increase the cracking,yielding and ultimate load of the test beam.Under the condition of the same pre-stress level,increasing the reinforcement amount can improve the yielding and ultimate load,and increase the structural stiffness.When the reinforcement amount is the same,much more pre-stress can increase the cracking load;(3)The pre-stress level has a significant effect on the failure form,cracking load,yield load and ductility.The crack width of the beam strengthened by TRM is reduced while the crack number is increased.As the increase of pre-stress level,the ductility of the strengthened beam is reduced;(4)The test beam is reinforced by the optimum prestress level,and the reinforcement effect is optimized synthetically.Combined with the model test,the paper considered the pre-stress loss and gave the method to determine the optimal pre-stress level;(5)The error between the calculated result of the simulation analysis method proposed in this paper and the measured value is within 10%,which proves that the simulation method is reasonable and reliable;...