Usman Ali
, Zakir Ullah, Muhammad Bilal, Sana Ullah
The strength and performance of the subgrade are evaluated by its resilient modulus (MR) for the design of flexible pavement. The MR is routinely assessed using the cyclic triaxial test by conducting as per the American Association of State Highway and Transportation Officials (AASHTO). Since the triaxial test facility is not widely available and expensive, the proposed study intends to develop an MR relationship with CBR. For this purpose, eight disturbed soil samples were gathered from the Potohar region of Pakistan. The non-destructive test for MR measurement utilizing a new sonic viewer was performed before and after carrying out the CBR. The travel times of the compression (Vc) and shear (Vs) waves were also measured to calculate MR before and after each soaking period. A new empirical correlation between MR and CBR was developed using the ultrasonic pulse velocity (UPV) approach. This correlation was then evaluated by comparing it to past MR and CBR relationships, resulting in a strong agreement. Moreover, another excellent correlation was found between MR and compression wave velocity (Vc). It was also observed that larger compaction effort (blows/layer) influenced the linear increase in MR, Vc, and Vs values. Finally, UPV for predicting the MR of loamy soils for pavement design was more cost-effective and accurate than the conventional techniques which are complex and time taking.
Usman Ali Zakir Ullah Muhammad Bilal Sana Ullah “Prediction of Resilient Modulus of Subgrade Loamy Soils Through Wave Propagation T Vol. 11 Issue 09 PP. 188-196 September 2024. https://doi.org/10.34259/ijew.24.1109188196.
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