Comparative investigation of laboratory and field compaction techniques for designing roller compacted concrete pavements (RCCP)

Abstract

ABSTRACT The disparity in the compaction mechanism associated with optimum moisture content determination & specimen fabrication process in the laboratory and actual pavement construction leads to either underestimation or overestimation of Roller Compacted Concrete Pavements (RCCP) performance. Hence, in this investigation, different techniques to design RCCP, such as modified Proctor (MP), vibratory hammer (VH), vibratory table (VT), and gyratory compactor (GC), are studied and compared with the field specimens (FS); the considered fresh, mechanical, and functional properties are dry density, compressive strength, flexural and indirect-tensile strength, elastic modulus, water absorption, porosity, and abrasion & skid resistance. The laboratory results indicated that the compaction mechanism greatly affects the fresh and mechanical characteristics of RCCP. Further, it was observed that the strength properties are sensitive to the cohesion between the particles, which in turn, depends on the compaction type used to compact the RCCP. Compared with the field slab, only MP could produce comparable properties; other techniques manifested either higher or lower fresh and mechanical properties, except flexural strength. Although GC could simulate the field compaction mechanisms, it cannot mimic field properties, which necessitates further optimisation of gyratory compaction parameters (angle, pressure, and gyrations) to represent the actual pavement properties. Moreover, to achieve the field properties, the considered compaction methods shall impart a degree of compaction near to theoretical maximum constituent density.