PVA Fiber Cement Stabilized Gravel Road Use Performance Study

Traffic development in our country,the people to the call of the road for im proving road is more and more is also high.At present,the cement stabilized m acadam is main of semi-rigid base material in highway construction of our count ry,it has high strength,stiffness big,strong integrity,good water stability and fr ost resistance and resistance to the fatigue of driving performance good character istic,therefore,has been widely applied to highway,city roads and airport road.But for cement stabilized macadam of semi-rigid pavement at the grass-ro ots level also has some shortcomings,such as low tensile strength,large brittlene ss,low flexible,under the effect of temperature drop and water reducing external cause to produce contraction,lead to the generation of cracks,the reflection to the pavement surface,destroyed the integrity and continuity of the pavement,mo re serious is that road surface water into the pavement structure,road surface cr acks even deep soil base,leading to premature pavement structure damage.This paper combined with the traffic investment group co.,LTD in anhui province scientific research project "the study of PVA fiber reinforced cement sta bilized macadam base,in view of the high grade highway damage status of crac king on the base of the cement stable macadam mixture,on the basis of investi gation and study of existing research results at home and abroad,selecting appro priate type polymer,poly(vinyl alcohol)(PVA)fiber.Through a lot of theoretica l analysis,laboratory test and field test,research doped polyvinyl alcohol(PVA)fiber in the dry shrinkage of the cement stabilized gravel base material deformati on,temperature shrinkage deformation and modulus of resilience and splitting str ength and splitting fatigue physical mechanics performance and polyvinyl alcohol(PVA)fiber mixing amount and adding length,etc.The relationship between the influencing factors and change law,and based on this research doped polyvinyl alcohol(PVA)fiber cement stabilized gravel base of fatigue life.Through the study:1)mixed with polyvinyl alcohol fibers,the material of the cement stable macadam mixture,unconfined compressive strength were the improvement of the different degree,but the increase amplitude are small.And with the increase of age,strength is also constantly improve,with the increase of pva fiber length,its strength has increased significantly.2)mixed with polyvinyl alcohol fibers,compressive modulus of resilience of cement stabilized macadam material can be reduced.And cement stabilized macadam material mixed with polyvinyl alcohol fibers with poly(vinyl alcohol)fiber mixed with the compressive modulus of resilience of linear downward trend,showed the polyvinyl alcohol fibers to reduce the material of the cement stable macadam mixture,the compressive modulus of resilience is effective.3)mixed with polyvinyl alcohol fibers can improve the flexural tensile strength of cement stabilized gravel material.And with the length increase of pva fiber,the effect is more apparent.4)drying shrinkage test results show that adding polyvinyl alcohol fiber cement stabilized gravel materials in different instars of average dry shrinkage coefficient is smaller than age period of ordinary cement stabilized crushed stone material,and can dry shrinkage crack resistance coefficient are older than age period of ordinary cement stabilized crushed stone material,shows that mixed with polyvinyl alcohol fibers to improve the drying shrinkage performance of cement stabilized gravel base has a great influence;5)dry shrinkage coefficient of the test results with the test in the process of water loss rate is larger,the filtration rate is small,average dry shrinkage coefficient is small,also affect the test results.