Self-Compacting Concrete (SCC) is a pioneering concrete that can gush beneath its own load, filling the formwork, and achieving full consolidation while maintaining sufficient cohesion to handle the concrete without segregation or bleeding issues. To develop EPS- fiber reinforced SCC, waste materials such as Expanded Polystyrene Beads (EPS) and waste plastic fibers (Polyethylene terephthalate (PET)) were incorporated. This study investigated the response of SCC to the incorporation of different ratios of PET fibers (0.35%, 0.5%, and 0.75%) and 10% of EPS particles and its impact on fresh and mechanical properties of SCC mixtures. Five SCC mixtures were designed, including the reference mixture, 10% EPS mixture, and three volume fractions (Vf) of PET mixtures. Test results indicated that EPS particles had an optimistic effect on fresh properties and a slight negative effect on mechanical properties. While PET fibers revealed a slight negative impact on fresh properties, they also improved mechanical properties. The highest and lowest values in fresh properties tests, including slump flow, T50, V-funnel, L-box, and sieve segregation were (780mm for (E %10) mix, 5.4 seconds for (0.75% f) mix, 19 second for (0.75% f) mix, 0.85 for (E %10) mix, and 10.77% for (R) mix), respectively and (670mm for (0.75% f) mix, 1.8 second for (E %10) mix, 6 seconds for (E %10) mix, 0 for (0.75% f) mix, and 3.28% for (0.5% f) mix), respectively. While, the highest and lowest values in mechanical properties tests, including density, ultrasonic pulse velocity (UPV), compressive strength, and splitting tensile strength were (2305 kg/m3 for (R) mix, 4.2 km/s for (R) mix, 48 MPa for (0.5% f) mix, and 3.66 MPa for (0.5% f) mix), respectively and (2170 kg/m3 for (0.5% f) mix, 4.03 km/s for (0.75% f) mix, 31 MPa for (E %10) mix, and 2.33 MPa for (E %10) mix), respectively
This study was conducted to examine the impact of plastic fibers (WPFs) in an effort to improve some of the features of self-compacting concrete (SCC) using Iraqi raw materials. Waste polyethylene terephthalate fibers (waste PET fibers) from used beverage bottles were added. Some tests were carried out to determine the effects of adding WPFs on the fresh properties of new concrete, while additional tests examined the mechanical properties of hardened concrete. Because of this, self-compacting concrete blends were created with a constant water-to-binder ratio of 0.32 and a binder content of 525 kg/m3. The designated plastic fiber percentages contents were 0%, 0.5%, 0.75%, and 1% of mix volume. Self-compacting concrete mixtures' fresh characteristics were assessed for slump flow diameter, T50 slump flow concurrently, V-funnel flow concurrently, and L-box height ratio. The 28-day density, compressive strengths and flexural strength of self-compacting concretes were also measured. The use of plastic waste fibers had a slight effect on reducing the density of the produced concrete and a negative effect on the fresh properties. The compressive strengths were improved by using WPFs, with the maximum improvement equal to (11.065%) when compared to those made from the reference mix
This paper presents and discuses some properties of self-compacting concrete SCC containing optimum contents of different types of cement replacement materials CRMs like fly ah, silica fume and limestone powder. The purpose is to evaluate the performance of SCC mixtures to choose the best one for strengthening purposes of corroded reinforcement concrete beams. In a preliminary work, the theoretical optimum contents of the above materials were specified using statistical program (Minitab) and they were verified experimentally. This verification based on checking fresh properties such as slump flow, T500, L-box and segregation resistance as well as compressive strength. The optimum contents of CRMs: 14% fly ash, 19% limestone, 18% silica fume plus fly ash and 11% silica fume were selected and studied. Compressive, tensile, and flexural strengths were examined, as well as the modulus of elasticity, water absorption and porosity (which reflect the related durability properties) were examined. Test results show that the optimum verified theoretical percentage of a combination of fly ash and silica fume, at 18% by weight of cement with a fixed water-binder ratio of 0.33 showed the best overall performance. It was deduced that this SCC mix gave the highest mechanical properties and the lowest porosity and water absorption. For example, the compressive strength increased by 36.25% as compared to SCC mix containing limestone powder. Further, the porosity and water absorption decreased by 120.8% and 164% respectively as compared to the above same SCC mix. Thus, it could be used for strengthening purpose of corroded RC beams.
This study presents an experimental research of Self-Compacting Concrete (SCC) properties containing waste plastic fibers (WPF). Adding waste plastics which resulting from cutting PET bottles as fibers to SCC with aspect ratio (l/d) equal to (28). To illustrate the effects of WPFs on the SCC, the current study was divided into two parts, the first part shows the effect of adding plastic fibers on the properties of fresh SCC, which include the ability flow, spread, passing and resistance to segregation, and the second part to evaluate the properties of hardened (mechanical) destructive and non-destructive, which include compression strength, flexural strength and ultrasonic pulse velocity test. One reference concrete mix was conducted and eight mixes contain WPF has been producing self-compacting concrete mixers containing a different volumetric ratio of plastic fibers (Vf) % percentages (0.25, 0.5, 0.75, 1, 1.25, 1.5, 1.75, 2) %. Three cubes samples were prepared for testing the compressive strength, three prisms were prepared for the test modules of rupture, one cylinder were prepared testing the modulus of elasticity. The experiments show that adding plastic fibers to SCC leads to an increase in the compression strength and modulus of rupture at 28-day as follows (42.30)% and (73.12)% respectively for mix ratio (1.5)% in comparison with the reference mix, which represent the best ratio of fibers, as such the results of testing the fresh concrete containing waste fibers showed that adding these fibers led a reduction in workability for SCC.