Currently, Texas recommends at least a 200 mm thick layer of Stone-Filled Hot-Mix Asphalt (SFHMA) mix as the main structural load-carrying layer in a perpetual pavement (PP) structure. To ensure adequate rutting resistance, the SFHMA mix-design characteristic typically consists of a moderately low asphalt-binder content (about 4.2%) and coarse aggregate gradation with a 25 mm nominal maximum aggregate size. However, perpetual pavements are relatively a new concept to Texas with limited experience or documented literature including the modulus properties and performance history; in particular for the rut-resistant SFHMA mixes. The objective of the work presented in this paper was therefore to evaluate and characterize the modulus properties of the SFHMA layers (mixes) based on laboratory dynamic modulus (DM) testing. Analysis of the results based on eight field in-service PP projects indicated that the SFHMA mixes are generally very stiff mixes with high moduli values averaging 8 000 MPa at 25 °C, 10 Hz; which is structurally essential for adequate rutting resistance. The laboratory DM test results were also well corroborated by field falling weight deflectometer (FWD) and multi-depth deflectometer (MDD) surface deflection measurements; which also indicated that the mixes are considerably less temperature sensitive with very marginal pavement surface deflections less than 1 mm even under high summer temperatures of around 42 °C. Summarily, the findings of this study indicated that the structural design moduli for the Texas SFHMA mixes (for perpetual pavements) should be in the range of about 6 000 to 8 000 MPa instead of the current specification range of 3 500 to 5 000 MPa, at 25 °C.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Characterizing the Modulus Properties of Texas Perpetual Pavements Based on Laboratory Dynamic Modulus Testing


    Contributors:

    Conference:

    Sixth International Conference of Traffic and Transportation Studies Congress (ICTTS) ; 2008 ; Nanning, China



    Publication date :

    2008-07-17




    Type of media :

    Conference paper


    Type of material :

    Electronic Resource


    Language :

    English






    Perpetual Pavements Design Criterions

    Cui, P. / Sun, L. / Zhang, L. et al. | British Library Conference Proceedings | 2007


    Perpetual Pavements Design Criterions

    Cui, Peng / Sun, Lijun / Zhang, Li | ASCE | 2007


    Significance of Confined Dynamic Modulus Laboratory Testing for Asphalt Concrete

    Zeiada, Waleed Abd-Elaziz / Kaloush, Kamil E. / Biligiri, Krishna Prapoorna et al. | Transportation Research Record | 2011