Study On Cross-tensioned Prestressed Concrete Pavement

Portland cement concrete pavement (PCCP) possesses both advantages, such as highstrength, good stability, proper cost, good sight on night riding etc, and disadvantages as toomany transverse joints, Joints are weakest parts of the porland cement concrete pavement, thedeterioration ofen happens at the transverse joints. The problem could be solved by theprestressed concrete pavement to eliminate transverse joints, But traditional prestressedconcrete pavement is often used by the way of longitudinal prestressed; this longitudinalprestressed concrete pavement can not solve the longitudinal cracking problems under theload. This study put forward the new concept of cross-tensioned prestressed concretepavement (CPCP), the pavement takes advantage of the compressive strength of concrete ismuch larger than tensile strength, the post-tensioned strands can be arranged diagonally,introducing compressive stresses in the concrete slab to improve the capacity of concrete,eliminate transverse joints, improve the driving comfort. Oblique force can produce twodirection prestress, it is suitable for the the force condition of pavement. At present, researchon cross-tensioned prestressed concrete pavement is blank in China and foreign countries.Systemic research on cross-tensioned prestressed concrete pavement is done in the paper.1. The finite model of cross-tensioned prestressed concrete pavement is first built in thepaper based on ANSYS. the concrete slab, the prestress tendon, the subgrade finite elementmodel are established, The prestress tendon and the dealing model of friction of slab bottomcorresponding to the condition of CPCP are put forward.2. Based on mechanical model of the cross-tensioned prestressed concrete pavement, thepavement numerical simulation is done, prestress loss is predicted by the formula and finiteelement simulation, the influence of prestress tendon acting position, friction coefficient，slabthickness，the angle and distance of prestress tendon, diameter are analyzed, tension sequenceis determined. In addition, anchorage zone is designed.3. A full scale model test was carried out indoor based on theoretical analysis, the resultsshow that stress distribution in the slab is consistent with the theoretical value. It is provedthat cross-tensioned prestressed concrete pavement is feasible.4. The influence factors on load stress and temperature stress are analyzed, this can provide the evidence for pavement structure design. The effect of a series of factors isdiscussed.5. Based on theoretical analysis and full scale model test, the test road was constructedinternationally, construction technology and construction process are put forward, and testroad is observed. The test results and service condition after completion show that the roadreaches design requirements, construction technology is feasible.6. Econmy property of different structure of cross-tensioned prestressed concretepavement, steel fiber concrete pavement and the traditional concrete pavement is evaluated bylife cycle cost analysis method. The result indicates that cross-tensioned prestressed concretepavement can prolong service life, decrease the cost of travel time prediction, vehicletraveling and accident, keep high service capacity during period of time and decrease time lifecycle greatly in project standard periods.