The California Bearing Ratio (CBR) is one of the most widely used tests in pavement and road design. It measures the load-bearing capacity of subgrade and base course materials, providing the key input data for flexible pavement thickness design to Austroads and Main Roads WA guidelines. Western Geotechnical Laboratory Services (WGLS) provides accredited CBR testing to AS 1289.6.1.1 and WA 141.1, available in both Soaked and Unsoaked configurations. Soaked CBR testing simulates worst-case moisture conditions and is required for most MRWA pavement designs. Unsoaked CBR is used where subgrade moisture is expected to remain stable. Both test variants are available from our NATA-accredited laboratory in Welshpool, Perth, with fast turnaround to support project schedules across Western Australia.
