Material And Engineering Application Research For Basalt Fiber Lean Concrete Base Course

Basalt fiber reinforced concrete is a new high performance cement compositematerials of great development internationally in recent years. Basalt fiber is toenhance concrete material’s resistance and tensile strength mainly, to reducestructure shrinkage deformation by the temperature’s change . By the early of thestress role, concrete and basalt fiber bear the stress role together, but the former bearthe temperature stress or load stress mainly. When the micro cracks happened in theconcrete , the fiber acrossing the cracks bear the stress mainly. But as the basecourse material, the study about basalt fiber chopped strand +lean concrete isvery little at home and abroad. The lean concrete mixed with basalt fiberchopped strand whether can improve the performance of the lean concrete, improveto what extent, also the fiber size and dosage is the worth studying problem; Inaddition basalt fiber reduce lean concrete reflection crack is is a key research of thelean concrete base course when useing.The paper baseing on the testing road of Ningdao highway (DaoXian section) inHunan province, combining domestic and foreign research, study mainly from thefollowing aspects of the basalt fiber lean concrete materials:1. The research on raw materials properties of basalt fiber. To introduce thebasalt fiber chemical composition, performance characteristics, the productionprocess, and to analyse of the physical and mechanical properties of fiber.2. To elect the reasonable dosage scope and optimum dosage of the basalt fiber.Through the five kinds of different dosage of basalt fiber lean concrete and not byadding basalt fiber lean concrete materials for the compressive strength, flexural,impact resistance test, to study and determine the reasonable dosage scope andoptimum dosage of the basalt fiber. In lean concrete base course, the reasonabledosage scope of basalt fiber chopped strand is 3-6 kg/m~3, the optimum dosage of thebasalt fiber is 4.8 kg/m~3.3. The paper study the influence of the basalt fiber to the workability of leanconcrete, the experimental results show that the basalt fiber will make the slump oflean concrete descend 20mm or so.4. The paper study the influence of the basalt fiber to the static concretecompressive of lean concrete, the experimental results show that, comparing with specimens which not by adding basalt fiber, the compression modulus is increased.but with the increase of the dosage of the fiber, the static compression modulus value‘s change range is not too much ,that is to say ,it improved the resistance of leanconcrete material elastic deformation of ability mixed the fiber, but the influence ofthe basalt fiber to lean concrete is not big.5. Through the construction of the entity project, to summarize constructiontechnology and methods of the basalt fiber lean concrete. And to set the 5m and 10mlongs cutting seam spacing of the testing road, mean to contrast its crackingperformance of entity verifies. the late stage observation of the testing road resultsshow that the basalt fiber is good at enhanceing lean concrete material’s resistancemainly, reduceing structure shrinkage deformation by the temperature’s change ,and reduceing the cracks of reflection.The last through the economic performanceevaluation of the entity engineering, to provide certain practical experience for thepromotion of the basalt fiber lean concrete base course materials in our country’shighway.