A study of durable and reliable reactive powder concrete containing rice husk fibers

Natural fibers have seen a surge in popularity over the past decade as a direct response to the growing number of people who are concerned about the environment. The use of natural fibers has many advantages, including their low cost and their little impact on the environment. Rice husk is a byproduct of milling rice and is frequently regarded as a waste product by many people. However, it has a number of possible applications, one of which is the use of its natural fibers in the production of bio-composites. In this paper, experimental work was carried out to study the effect of Rice Husk Fibers with a volume fraction of one percent on the properties of Reactive Powder Concrete (RPC), utilizing various temperatures curing for four hours due two days after hardening the sample directly, and the optimal temperature that will give the highest strength will be adopted to study the effect on some mechanical properties. Rice Husk Fibers were added to the RPC mixture at a volume fraction of one percent. These characteristics include the compressive strength, dry density, and slump of the material. According to the findings, the compressive strength of the RPC grew by 7.4%, while the dry density reduced by 0.69 % after being heated to 60 °C for 28 days. On the other hand, the RPC's workability decreased by 5.62 % when compared to the reference mixture

The Effect of Different Curing Temperatures on Properties of Reactive Powder Concrete Reinforced by Micro Steel Fibers

Reactive Powder Concrete (RPC) is a type of high-performance concrete that is known for its exceptional strength and durability also RPC is one of the new composite materials that allow for the most efficient use of materials, which benefits the concrete industry economically. Additionally, it improves environmental sensitivity. The main objective of this paper is the determine some characteristics of RPC, such as (compressive strength and fresh density) after exposure to different curing temperatures (60, 120, and 200) oC for 4 hours due two days. This study involves many variables such as micro steel fibers content with 1% by vol. of reactive powder concrete samples as well as elevated temperature. It was discovered that the optimum temperature that was used after conducting the tests was 60 Celsius, as it gave the best results for the mechanical properties of RPC, which were adopted in the rest of the tests. The value of fresh density increased by about (1.95%) and compressive strength increased by about (33.3%) at 60 oC for the age of 28 days in contrast to the reference mixture

Effect of internal curing on performance of self-compacting concrete by using sustainable materials

This paper is devoted to investigate the effect of internal curing technique on the properties of self-compacting concrete. In this study, self-compacting concrete is produced by using limestone powder as partial replacement by weight of cement with percentage of (5%), sand is partially replaced by volume with saturated fine lightweight aggregate which is thermostone aggregate as internal curing material in three percentages of (5%, 10%, 15%) for self-compacting concrete, and the use of two external curing conditions which are water and air. The experimental work was divided into three parts: in the first part, the workability tests of fresh self-compacting concrete were conducted. The second part included conducting compressive strength test and modulus of rupture test at ages of (7, 28 and 90) days. The third part included doing the shrinkage test at age of (7, 14, 21, 28) days. The results show that internally cured self-compacting concrete has the best workability and the best properties of hardened concrete which include (compressive strength, modulus of rupture) of externally cured self-compacting concrete with both water and air as compared with reference concretes. Also, the hardened properties of internally cured self-compacting concrete with percentage of (5%) with thermostone aggregate is the best as compared with that of percentages (10% and 15%) in both external curing conditions. In general, the results of shrinkage test have shown reduction in shrinkage of internally cured self-compacting concrete as compared with reference concretes and this reduction increases with increase in the thermostone aggregate content-within-self-compacting-concrete