Research On The Flexural Behavior Of Textile Reinforced Concrete Plate

Textile Reinforced Concrete(TRC)is a novel kind of composite construction material consisting of a fine-grained concrete matrix and high-performance textile made of various fibers,such as alkali-resistant(AR)glass,carbon or polymer fibers.TRC exhibits several advantages,including excellent load bearing capacity,durability,ductility,and corrosion resistance.However,the utilization of fiber textile is low,and the fiber textile-concrete interface is easy to debond during the application of this material.Accordingly,this paper tries to obtain better properties of basalt textile reinforced concrete(BTRC)plate by applying prestess on the textile and meanwhile,adding steel fibers in the concrete.The corresponding experimental cases are established to explore the flexural behaviors of BTRC plate.The following results can be obtained:(1)The three-point bending tests were conducted to investigate the effects of various textile layers,steel fibers volume contents and prestress levels on the flexural behaviors of BTRC plate.With the increase of the textile layers,the flexural strength and toughness of BTRC plate are improved.Prestress on the textiles improves the first crack stress and the post-cracking flexural stiffness,but decreases the ultimate deflection of BTRC plate,while no obvious change occurs for the flexural strength.Adding steel fibers in matrix is revealed to positively affect the first crack stress,flexural strength and toughness of BTRC plate,and the effect of steel fibers on the flexural strength is more prominent after applying prestress on the textiles.Moreover,the increase of textile layers and steel fibers contribute to the crack pattern characterized by more and finer cracks;however,prestress on the textile reduces the crack number and increases the crack spacing.(2)The theoretical calculation formula of flexural bearing capacity of multilayered TRC plate is proposed.The cracking stress and flexural strength of BTRC plates from different cases are calculated,which agrees well with the experimental results.In addition,the deflection of BTRC plate is calculated by effective moment of inertia method,and further,the corresponding fleuxral stress-deflection curve of BTRC plate is obtained.(3)The corresponding 3D finite element model is established to conduct parameters analysis on flexural behavior of BTRC plate.The model effectively simulated the strain-hardening behavior after cracking of BTRC plate after cracking.The flexural stress-deflection curves of multi-layer BTRC plates obtained by finite element simulation agree well with the experimental ones.Meanwhile,the damage evolution curve of the BTRC plate under flexural loading is obtained by simulation analysis.With the increase of the prestress level,steel fiber volume content and length,the development of damage slows down.(4)A 2D finite element model of TRC plate is established,and cohesive element,which can simulate cracks and fracture,is introduced into the model to successfully simulate the multi-cracking property of BTRC plate under flexure.In addition,the stress distribution along the bottom fiber bundle is obtained.After adding the steel fibers,the stress increment on the fiber bundle at the crack decreases,thus the stress inhomogeneity is reduced,and additionally,the crack spacing is reduced.