Study On Durability Of The Cross-tensioned Pre-stressed Concrete

The cross-tensioned prestressed concrete pavement is a new type of cement concretepavement, which uses double-slant pre-stressed steels, which makes the pavement haveprestressing effect in both longitudinal direction and transverse direction, and it improves thebearing capacity effectively, reduces the number of transverse crack, enhances thecompactness of cross-tensioned prestressed concrete and prolongs the life. Thecross-tensioned prestressed concrete is the major components of the new type of cementconcrete pavement, whose durability has an significant effect on the durability and economyof cross-tensioned prestressed concrete pavement, so this research studys on the durability ofthe cross-tensioned prestressed concrete.Basing on the relevant research results at home and abroad, according to characteristicsof cross-tensioned prestressed concrete, this research puts forward to changing the durabilityof cross-tensioned prestressed concrete by adding fly ash and waste asphalt mixture. First, thisstudy optimizes raw material and determines the reference mixing ratio; then studying thepermeability resistance performance, frost resistance performance and abrasion resistance ofthe concrete with different dosage of fly ash and waste asphalt mixture, proposing the bestmixing ratio basing the durability, and establishing corresponding model to carrying out asimulation of chloride ion penetration infiltration with best mixing ratio through MATLAB.Its durability can be significantly improved by mixing the fly ash, but excessive or too smallmixing amount is not obvious for improving durability, tests shows that the optimum mixingamount is20%; waste asphalt mixture has a perceptible improvement in impermeability andfrost resistance, but has an adverse affect on abrasion resistance, tests shows that the optimumdosage is20%. The chloride ion penetration simulations indicate that the resistancing tochloride ion penetration life of the cross-tensioned prestressed concrete with best mixing ratiois far longer than the design life. Through studying durability of the cross-tensionedprestressed concrete durability, not only providing technical support for cross-tensionedprestressed concrete durability design, but also playing an important role in recycling ofindustrial residue and waste materials.