Influence of moisture on Resilient Deformation behaviour of Unbound Granular Materials

This study investigated the influence of moisture on the Resilient Deformation (RD) properties of Unbound Granular Materials (UGMs). A typical UGM used in pavement constructions with three different grain size distributions were tested with a range of moisture contents using Repeated Load Triaxial tests (RLTTs). From the European standard, the procedure for the study of the RD behaviour was used where each stress path is applied for 100 cycles. Additionally, the Multi-Stage (MS) loading procedure for the study of the permanent deformation behaviour were used where each stress path is applied for 10,000 cycles, to compare the results using the two test procedures. Results showed that resilient modulus (MR) generally decreased with increase in moisture, where the finer grading was more affected. However, for the MS RLTTs, after a large number of load applications, some increase in MR with increasing moisture was observed. This happened when the moisture content increased up to close to the optimum; above the optimum, MR always decreased. This may be due to Post-Compaction (PC) aided by moisture in MS RLTTs where a large number of load cycles were applied.

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6
Oct

Open seminar with Mistra SAMS international scientific advisory...

Mistra SAMS international scientific advisory panel (ISAP) is visiting Stockholm, and the program will host an open seminar where the panel members will give talks in their area of expertise.
19-20
Oct

ERPUG 2017

The five year anniversary of  European Road Profile Users' Group (ERPUG) Forum will take place at Ramboll head quarter, Copenhagen, Denmark October 19-20, 2017. 

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2017-05-02

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2017-05-02

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