Research On Mechanical Properties Of Joints Of Permanent Formwork Composite Structures With Ribbed Fiber Reinforced Concrete Used In Google Dictionary

Ribbed fiber concrete permanent formwork is a new type of precast formwork,which is made of concrete mixed with fiber.The formwork is equipped with fine steel reinforcement,and the inner surface of the formwork is ribbed by certain technology.This kind of formwork is simple to make,convenient to install and has excellent mechanical properties.This research group has studied the force of such formwork composite plates,beams and columns.The test results show that the ribbed permanent formwork has a constraint on post-pouring concrete,and can delay the development of cracks and improve the bearing capacity of components.When this kind of formwork is popularized in engineering,the mechanical behavior of the ribbed permanent formwork should also be analyzed.In order to study the seismic performance of the composite frame beam-column joints of ribbed permanent formwork under the action of low cyclic repeated loads,two specimens of composite beam and column joints of ribbed formwork and one specimen of cast beam and column joints were made.By analyzing the failure characteristics in the process of loading,including the hysteresis curves,skeleton curves,ductility and energy dissipation capacity,strength degradation,can get the following conclusion: ribbed formwork composite seismic performance of beam-column joints was slightly better than the concrete beam-column joints,lies in the strength of the ribbed formwork higher toughness,better to have bound effects on core concrete,specimens of stiffness degradation slower,ductility and energy dissipation ability is stronger.The finite element software ABQUS was used to simulate the mechanical behavior of the specimen under repeated load,and the simulated value was compared with the sample value.The simulated value was basically consistent with the test value and within the error range.According to the results of the model analysis,both the superimposed beam and column joints of the ribbed permanent formwork and the cast beam and column joints are subjected to beam end bending failure,which is ductile failure.In the equivalent plastic strain PEEQ analysis of the joint model,it can be seen that the ribbed permanent formwork has a good binding effect on the core concrete and can delay the plastic deformation of the composite joints.On the basis of experimental analysis,the mechanical mechanism of the core concrete restrained by ribbed permanent formwork is simplified,and the calculationformula of beam end flexural bearing capacity considering the constraint of ribbed formwork is put forward.The calculated values are consistent with the experimental values,which can provide a basis for the application of ribbed permanent formwork.