This experimental study is focused on the performance of appropriate grout/mortar for pre-placed aggregate concrete (PAC) incorporating superplasticizer in the mortar mixture regarding the flowability and strength of grout or mortar. Twenty-one samples of specimens were prepared. The parameter tests consist of water-cement ratios, cement sand ratios and variation dosages of superplasticizer. To examine the flowability/fluidity of grout or mortar, the flow cone test was applied. The flow cone test result indicated that there were three proportional grout that can meet the requirement for fluidity according to ASTM C-939. The compressive strength of specimens was tested. It was concluded that the composition of grout with containing the percentage of 0.7% by weight of cement of superplasticizer as chemical admixtures at a water-cement ratio of 0.6 and a cement-sand ratio of 0.5 is the proper composition of grout for pre-placed aggregate concrete (PAC).

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Self-compacting concrete is an innovative concrete technology with higher flowability properties by adding the mineral admixtures such as superplasticizers and not necessary to vibrate concrete. The banana fibers were used in this investigation because banana fiber is an environmentally friendly material with good properties compared to synthetic fiber. The experimental test consisted of two phases of research, i.e., preliminary research, which had the aim to investigate the appropriate percentage of superplasticizer in the mixed composition of self-compacting concrete. The percentages of superplasticizers were 0.7%, 1%, and 1.4%. The second phase of research on the effect of additional banana fiber on self-compacting concrete was carried out, examining workability, compressive strength, and the splitting tensile strength of concrete. In this research, the percentages of fiber were 0.12%, 0.3%, and 0.5% of the cement weight, and evaluated the effect of fiber treatment. The treated fibers mean that the fiber is immersed in NaOH solution or named as a delignification process. The hardened concrete specimen was used for determining the mechanical strengths, such as the compressive strength and split tensile strength tests. The test results found that the optimum value for superplasticizer dosage was 0.7% of cement weight, which can fulfill the whole criteria of fresh concrete and hardened SCC concrete. Furthermore, the specimen with the adding banana fiber of 0.12% by cement weight and treated fiber indicated a decrease in workability. Compared to the control concrete, it inversely increased compressive strength up to 44.36% and tensile strength up to 17.78%.

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