The shrinkage cracking behavior in reinforced reactive powder concrete walls

الملخص EN

In this study, the reduced scale wall models were used (they are believed to resemble as much as possible the field conditions) to study the shrinkage behavior of reactive powder concrete (RPC) base restrained walls.

Six base restrained RPC walls were casted in different length/height ratios of two ratios of steel fiber by volume in Summer.

These walls were restrained by reinforced concrete bases to provide the continuous base restraint to the walls.

The mechanical properties of reactive powder concrete investigated were; compressive strength between (75.3 – 140.1) MPa, splitting tensile strength between (5.7 – 13.9) MPa, flexural tensile strength (7.7 – 24.5) MPa, and static modulus of elasticity (32.7 – 47.1)GPa.

Based on the observations of this work, it was found that the cracks did not develop in the reduced scale of the reactive powder concrete (RPC) walls restrained from movement at their bases for different L/H ratios (2, 5, and 10) and for two ratio of steel fiber (1% & 2%) during 90 days period of drying conditions.

Moreover, the shrinkage values increase toward the edges.

Based on the results of this work, the increase in the maximum shrinkage values of walls with 1% steel fiber were (29%, 28%, 28%) of the maximum shrinkage values of walls with 2% steel fiber of length/height ratios of (2, 5, and 10) respectively.

The experimental observation in beam specimens showed that the free shrinkage, tensile strain capacity and elastic tensile strain capacity (at date of cracking) of beams with 1% steel fiber were higher than the beams with 2% steel fiber by about (24%), (45%) and (42%) respectively