Compressive Strength And Economic Viability Of Roller Compacted Concrete (Rcc) Pavement Containing Pulverized Sand And Fly Ash
In the Philippines, roller compacted concrete (RCC) is a new engineering material having the same basic ingredients as the conventional concrete but of different mix proportions. With the used of fly ash as partial replacement of cement in the construction of RCC pavement not only increased its workability and strength but also attributed RCC in utilizing industrial residuals and reducing the use of non-renewal resources. This study determined the compressive strength of RCC slab when compacted by a 68-kg soil compactor and compared theoretical direct costs of RCC from conventional concrete pavement. The construction of RCC slab was based on the Soil Analogy method suggested by the American Concrete Institute (ACI). Modified Proctor test was used in determining the maximum dry density (MDD) and optimum moisture content (OPC). Three (3) RCC slabs (0.91 x.70 x.15 m) were constructed and water cured. A total of 18 core samples were extracted from the 3 slabs, six cores for each slab. The cores were then tested for compressive strength determination following ASTM C39. The obtained compressive strength of 3 days curing time is 18.44 MPa, while for 28 days curing duration is 27.85 MPa (4039.78 psi). The results of testing the compressive strength of cored samples were 28-62% higher than the designed strength of portland cement concrete (PCC) pavement. From 3 days to 28 days of curing, the strength increased to 40.65%. In the estimation of direct costs, 33.53% can be save when using roller compacted concrete in the construction of pavements, instead of conventional portland cement concrete. Therefore, roller compacted concrete pavement is an economical and sustainable pavement alternative for portland cement concrete pavement secondary roads.
Index Terms� Roller Compacted Concrete Pavement, Compressive Strength, Vibratory Compaction, Sustainable Pavement.