Evaluation of Structural Behavior of Precast Prestressed Concrete Pavement with Finite Element Analysis

Abstract

A full-scale precast prestressed concrete pavement (PPCP) system was constructed and evaluated under actual traffic load conditions to develop the design guideline under Florida conditions. This test section showed good load transfer efficiency and riding quality. However, information was lacking about its structural response and potential performance. A three-dimensional finite element model was developed for stress analysis of PPCP under critical loading conditions. The developed three-dimensional model was calibrated by using deflection data obtained with a falling weight deflectometer. The model was used to perform a parametric analysis to determine the effects of critical loading location, concrete modulus, coefficient of thermal expansion of concrete, loss of prestress force, and subgrade stiffness under typical Florida conditions. Results of the parametric study indicate that the maximum stresses in the concrete increased significantly as the concrete modulus and coefficient thermal expansion increased. Because of the increase in flexural strength associated with the increase in elastic modulus of the concrete, an increase in elastic modulus of the concrete results in a decrease in the computed stress-to-strength ratio under critical load–temperature conditions. The PPCP system that was evaluated appeared to have a good predicted pavement performance with a computed stress-to-strength ratio of less than 0.5, with up to an additional loss of 20% of prestress force in the longitudinal and transverse directions. Variations in the base and subbase properties were found to have a minimal effect on the maximum induced stresses in concrete. This finding indicates that the PPCP system is appropriate for a wide variety of subbase and subgrade conditions.

Bending mechanical properties research on prestressed airport concrete pavements

“…In cast-in-place prestressed concrete pavements, sometimes the prestressed reinforced bar is set at a position slightly below the mid-level the pavement thickness. 6 Further, for the assembling-type (prefabricated) pavement slabs, the stresses imposed in the links during transportation, hoisting, assembling and so forth also need to be considered. This means that by applying an eccentric prestress on an assembling-type concrete pavement slab may cause instability in the above links thereby damaging the slab.…”

“…Before using a mold, a 20 mm diameter round hole has been drilled at the centroid of a square template on each end, so that a thin‐wall steel tube also 20 mm in diameter can run through the axis of the entire beam and a narrow passage can be reserved for the tensioned reinforced bar. In cast‐in‐place prestressed concrete pavements, sometimes the prestressed reinforced bar is set at a position slightly below the mid‐level the pavement thickness . Further, for the assembling‐type (prefabricated) pavement slabs, the stresses imposed in the links during transportation, hoisting, assembling and so forth also need to be considered.…”

“…Instead, the posttensioning method has been used to apply prestress on the beam specimens. Referring to the 1–2 MPa prestress inside ordinary prestressed concrete pavement, an anchor shank tension meter has been used in the test process to exert pressures of 1, 2, 3, and 4 t (metric ton) on the base plates, so as to impose prestress of 0.44, 0.89, 1.3 3, and 1.78 MPa on the beams. A total of five groups of beam specimens (three in each group) have been prepared.…”

“…According to several studies, when meeting the minimum thickness requirement of 20 cm, the thickness of prestressed concrete pavements can be reduced to 40–60% of the ordinary concrete pavements while their life span expand five times longer. So, this technique can effectively enhance the fatigue resistance of concrete pavements …”

“…effectively enhance the fatigue resistance of concrete pavements. [5][6][7][8] Besides being used for the construction of high-grade concrete pavements, the prestressing technique can also be combined with the assembling-type pavement technique for both the quick repair of local pavements and the quick overall construction of emergency airport pavements. The emergency airport pavements are of particular practical significance for the transport of humanitarian relief goods after a disaster, the construction of frontline airfields in a war, and the building of permanent airfields under other unfavorable conditions.…”