ECONOMIC VIABILITY AND COMPRESSIVE STRENGTH OF ROLLER COMPACTED CONCRETE PAVEMENT (RCCP)

Carmel  B. Sabado-Burlat,

ECONOMIC VIABILITY AND COMPRESSIVE STRENGTH OF ROLLER COMPACTED CONCRETE PAVEMENT (RCCP)

Abstract:

The pavement industry is one of the areas where sustainability must be practiced. Roller Compacted Concrete (RCC), a zero-slump concrete, is a new engineering material here in the Philippines having the same basic ingredients as conventional concrete but of different mix proportions. It is constructed without forms and reinforcement. Fresh RCC mix is dry enough to support a roller while being compacted and wet enough to accommodate complete hydration of cementitious materials. The foremost objective of this study is to determine the compressive strength of RCC slab when compacted by a 68-kg soil compactor. Soil Compaction Analogy Method (ASTM D-1557) was used in determining the maximum dry density (MDD) and optimum moisture content (OPC). A compaction pattern is observed with 5 passes of the compactor in each direction. Three (3) RCC slabs (0.91 x.70 x.15 m) were constructed, and water cured for 3 days, 14 days, and 28 days respectively. Properties of crushed ¾” aggregates, rounded ½” aggregates, natural sand, and cementitious materials (Portland Type 1 and Fly ash) were all tested prior to using it in the experiment. A total of 18 core samples were extracted from the 3 slabs, six for each slab. The cores were then tested for compressive strength determination following ASTM C39 Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens. Initial results showed that the strength attained by RCC is 32% higher than the designed strength developed by DPWH for the 3-day maturity and 47% higher for the 14-day maturity time. It is recommended that the observation of the maturity of concrete be extensive and to be observed for a longer period of time to evaluate further its characteristics and behavior. Lastly, an in-depth study of the economic viability of RCC pavement as a substitute to Portland cement concrete pavement and a comparison in terms of cement content, construction time, and production unit cost must be conducted.