Scientists have recently started looking for new ecologically friendly and sustainable materials. Construction materials are among the numerous widely employed materials, and it is normally acknowledged that they have an apparent detrimental influence on the environment. Thus, the contribution of this paper is to describe the palm frond natural fibers' effect on concrete's mechanical characteristics. Since concrete is a brittle material, the goal of this research is to increase the tensile strength of concrete by using organic fibers (palm frond fibers), a waste product. In order to determine the ideal percentage of fibers, the following percentages were tested: 0.25, 0.5, 0.75, and 1% by volume of concrete. On dry density, compressive strength, and tensile strength, the impacts of fibers were investigated. The density of concrete decreased with increasing fiber ratios. The compressive strength slightly decreased, while the splitting strength significantly improved. According to the results, the best amount of palm frond fibers that can be add to concrete is 0.75% by volume.
This study aims to improve different properties of sustainable self-compacting concrete SCC containing treated and modified polyethylene terephthalate PET fibers. For this purpose, gamma ray surface treatment and geometric modification were utilized for the used PET fibers. Concrete fresh properties include slump flow, T500mm, L-box and sieve segregation while mechanical properties include compressive, split tensile strength, flexural strength, static modulus of elasticity and impact strength. Further, physical properties and related durability properties comprise dry density, ultrasonic pulse velocity, porosity and water absorption. The results obtained demonstrated that the treatment and the modification used for the PET fibers slightly reduced the fresh properties of produced sustainable SCC (slump flow, T500 mm, L-Box and sieve segregation). However, they were within the limits of the SCC specification as reported in EFNERC guidelines. Further, concrete hardened properties in terms of compressive strength, splitting tensile strength, flexural strength, modulus of elasticity, impact strength, ultrasonic pulse velocity, decrease in the dry density, decrease in porosity and water absorption increased significantly.
This research paper is an attempt to reuse plastic waste fibre resulting from plastic sections industry as an additive to concrete matrix. The relationship between fibre volume fraction and mechanical properties of concrete and re-inforced concrete tiles was investigated. Three volume fractions of fibre ( 0.5 % , 1 % and 1.5 % - by volume of concrete ) were used through the experi-mental program. Tests’ results proved a slight decrease in concrete compres-sive strength as plastic fibre was added compared with the reference mix. Flexural behaviour of concrete tiles was enhanced as adding fibres. Adding fibre to Concrete results in a negligible reduction in concrete density. Fibre with high volume fractions improved Splitting tensile strength compared to the reference mix.
The impact resistances of concrete slabs have a different volume fraction replacement of waste plastic aggregate has been examined in this study as a fine aggregate as: 0% (reference), 10%, 20% and 30%. These tests include the splitting tensile, density, compressive strength. Also, the (ultrasonic pulse velocity tests) was carried out. Repeated falling mass was used in order to carry out the low-velocity impact test in which a 1300 gm steel ball was utilized. From a height of 2400mm, the ball falls freely on concrete panels of (500×500×50 mm) with a network of waste plastic aggregate. As per the results, a prominent development was seen in the mechanical properties for mixes involving polyethylene aggregate up to 20% as compared to the reference mix. A significant development was seen in low-velocity impact resistance of all mixes involving waste plastic fine aggregate as compared to reference mix. As per the results, the greater impact resistance at failure is offered by the mix with (20%) waste plastic aggregate by volume of sand than others. The reference mix increased by (712.5%).
The presented work investigates the effect of addition admixture (cement kiln dust) to concrete as a partial replacement of cement weight. Cement kiln dust was added by (10,30,50)% of cement weight.Four mixes were selected, three of them contain cement kiln dust (CKD) and one reference mix without any admixture for ages (7,28,90) days. Compressive strength ,flexural strength, ultra-sound velocity (UPV), slump, splitting tensile strength and static modulus of elasticity were tested.The test results indicated that the use of (CKD) led to significant decreasing in concrete strength in general and this decreasing increases with the increasing of (CKD), for example at 28 day the compressive strength of reference concrete (A) was 35 MPa, while the compressive strength of (B,C,D) contain (10,30,50)%CKD were (28,25,22) MPa respectively.