Kajian Sambungan Pencoran Beton

The casting of concrete mixes in the formwork should be done continously in oder to produce homogenous concrete structures. The implementation of the concept sometime is not possible due to restriction of materials, equipments, and climate antisipation such as drying shrinkage. Due to the reasons above, the casting of concrete mixes are done segmentally but allowing a special treatment at the casting stop (between fresh and hardened concrete), i.e. by making the surface rough, covering the surface with cement paste, or by giving a bonding agent. The research was conducted to investigate the flexural and shear strenght of beam specimens made with casting stop placed at the middle of the span. The investigation was run by making cylinder specimens for compressive strength test and beam specimens for flexural and shear strength test in four types, i.e. ( I ) without casting stop, (2) with casting stop and Sikatop 77D as a bonding agent, (3) with casting stop and cement paste as a bonding agent, and (4) with casting stop and no bonding agent. All specimens were tested in 28 days of old. The results showed that the casting stops decreased flexural and shear strength of 2-10% and 5-23% respectivelly. Nevertheless, the value of the strengths resulting from the investigation were greater than that written in SNI-03-2847- 1992. Furthermore it could be concluded that there will be no effect in the design of concrete structures due to the casting stops as long as the casting and compacting of concrete mixes are done perfectly