Experimental Investigation of Wheel-Load Induced Strain Responses in Roller Compacted Concrete Pavements

A recently completed study at the Pavement Research Facility of Louisiana showed that, thin roller compacted concrete (RCC) pavements has great potential to be used for low to medium volume roadway applications where a large amount of heavy and/or overweight trucks are often encountered. However, the existing RCC pavement design procedures are solely empirically-based and only applicable for heavy industrial pavement’s thickness design. The objective of the current study is to develop a mechanistic-empirical (M-E) based RCC thickness design procedure through the evaluation of cracking mechanism and joint performance of RCC test sections under accelerated pavement testing. Two 203-mm thick RCC pavement sections were constructed for this study: one section built over a 216-mm soil cement base and the other over a 305-mm cement treated soil base. Each section was instrumented with one fiber optic strain plate, over which 16 fiber optic strain gages and 3 temperature gages were embedded. Those sensors were positioned apart on the plate to measure wheel load-induced transverse and vertical strains at two critical positions (i.e. the top and the bottom of the RCC layer). This paper documents an investigation of the strain responses on RCC pavements under the APT loading with regard to different load positions, levels, repetitions and temperatures. The measured strains were then used to compare, verify and calibrate a developed finite element model, which will eventually be used for the RCC fatigue performance and thickness design.