Study On Durability Properties Of PVA Fiber Reinforced Cementitious Composite Containing Nano-particles

In recent years,great attention has been paid to PVA fiber reinforced cementitious composites due to its ductility and high toughness and the characteristics of strain hardening and multiple cracking.And a large amount of researches have been carried out at home and board.Nano material has shown great potential applications in many fields as a new material with the unique nano effect.As research continuing and cost falling,nano materials have expanded into the actual project.However,in the present study,the research on the durability performance of PVA fiber reinforced cementitious composites containing nano-particles are rare.Through a large number of experiments,this paper shows the effect of the durability performance influenced by the PVA fiber volume fractionand the types and dosages of nano-particle.The main contents are as follows:(1)The preparation theory of PVA fiber reinforced cementitious composites containing nano-particles was analyzed,and 15 series of mix proportion were determined.he influencing rule of the PVA fiber volume fraction and the nano-particles content on the work-ability of PVA fiber reinforced cementitious composites containing nano-particles was obtained though the test of slump spread.(2)With 28 d as test age,the freeze—thaw resistance was studied by the tests of beam specimens which size is 100mm×100mm×400mm.The influencing rule of the PVA fiber volume fraction and the nano-particles content on the freeze—thaw resistance of cementitious composites were obtained.(3)With 28 d as test age,the carbonation resistance was studied by the tests of the cube specimens which size is 100mm×100mm×100mm.The influencing rule of the PVA fiber volume fraction and the nano-particles content on the carbonation resistance of PVA fiber reinforced cementitious composites were obtained.(4)With 28 d as test age,the permeability resistance was studied by the tests of Ellipse specimens which size is 175 mm on the bottom,185 mm at the end and 150 mm high.The influencing rule of the PVA fiber volume fraction and the nano-particles content on the permeability resistance of cementitious composites were obtained.(5)With 1d as test age,the crack resistance was studied by the tests of tablets pecimens which size is 900mm×600mm×20mm.The influencing rule of the PVA fiber volume fraction and the nano-particles content on the crack resistance of cementitious composites were obtained with analyzing the test results by the evaluation method for the crack resistance of the cement mortar crack resistance test method.