Impact of temperature curling, loading, and structure on critical edge and stress-based load transfer efficiency of rigid airfield pavement

The objective of this study is to analyze the effect of temperature induced Portland. Cement Concrete (PCC) slab curling and loading, on both critical edge stresses and stress-based load transfer efficiency (LTE(S)) at the joint. This study focuses on the structures of Construction Cycle 6 (CC6) at the National Airport Pavement Testing Facility (NAPTF) located at the William J. Hughes Tech Center in Atlantic City, NJ. The Federal Aviation Administration's Finite Element Analysis program FEAFAA was used to analyze temperature effects on critical stresses and LTE(S) at the joints for CC6 structures. The current FAA design procedure assumes constant LTE (S) of 25% at the joints and does not directly consider temperature slab curling effects. Recent studies on LTE(S) recommend that the ambient temperature be considered in design of rigid pavements. Previous studies have also shown that the seasonal and daily temperature variations as well as the temperature differentials at the top and bottom of the PCC slab can affect the critical edge stresses at the joint and the LTE (S) of the pavement. In this study, three modulus of rupture (MOR) values of the PCC layer 500, 750 and 1000 psi (3.45, 5.17, 6.9 MPa), which correspond to an elastic modulus (E) of 3800ksi, 5700ksi, and 7600ksi (26.2, 39.3, 52.4 GPa), over two different support structures, a bituminous stabilized base (500ksi, 3.45 GPa) and Econocrete stabilized base (700ksi, 4.83 GPa), were evaluated. The critical edge stresses and LTE (S) values under a 16.7 square in. single wheel load at two different load magnitudes (50 and 100kips (223 and 445 kN)) and varying temperature gradients (-1.0°F/in. to +1.0 °F/in. (-0.22°C/cm. to +0.22°C/cm.)) were analyzed. This finite element analysis has shown that edge stresses and load transfer efficiency due to temperature curling and loading are sensitive to the stiffness of the PCC layer. As the MOR and E increase the pavement becomes more susceptible to these temperature effects. However, this effect becomes less significant as the load on the slab increases. Stabilized base type was found to have a negligible effect on edge stresses and LTE (S).

Language

  • English

Media Info

  • Pagination: pp 59-68
  • Monograph Title: Bearing capacity of roads, railways and airfields: proceedings of the ninth International Conference on the Bearing Capacity of Roads, Railways and Airfields: Trondheim, Norway 25-27 June 2013. Vol 1-2

Subject/Index Terms

Filing Info

  • Accession Number: 01596505
  • Record Type: Publication
  • Source Agency: Swedish National Road and Transport Research Institute (VTI)
  • ISBN: 9788232102853
  • Files: ITRD, VTI
  • Created Date: Apr 21 2016 12:20PM