Effects of Hybrid Polypropylene-Steel Fiber Addition on Some Hardened Properties of Lightweight Concrete with Pumice Breccia Aggregate

Abstract

Lightweight concrete application in construction field is growing rapidly in these recent years due to its advantages over ordinary concrete. In this paper, pumice breccia which can be found abundantly in Indonesia is proposed to be utilized as the coarse aggregate. In spite of its benefits, lightweight concrete exhibits more brittle characteristics and lower tensile strength compared with normal concrete. On the other hand, fiber addition into concrete has become widely used to improve its tensile properties. Furthermore, the utilization of hybrid fiber in a suitable combination may potentially improve the mechanical properties of concrete. This paper experimentally examines the effects of hybrid polypropylene-steel fiber addition on some hardened properties of pumice breccia aggregate lightweight concrete. Five groups of test specimens with fixed volume fraction of polypropylene fiber combined with different amounts of steel fiber were added in concrete to investigate the density, compressive strength, modulus of elasticity, splitting tensile strength, and the modulus of rupture of the concrete mixtures. Test results indicate that hybrid fiber addition leads to significant improvement to the compressive strength, modulus of elasticity, splitting tensile strength, and the modulus of rupture of the pumice breccia lightweight aggregate concrete and meet the specification for structural purposes.

M12 Monofilament Tipi Polipropilen Lif Takviyeli Betonların Özellikleri

“…In similar studies in the literature, it was reported by researchers that the compressive strength results of PP fiber reinforced concrete were obtained in a similar way and that the low strength of the fibers in compression decreased the compressive strength of the concrete [2,4,5]. Widodo et al used steel fiber along with PP fiber to increase compressive strength and achieved better results in compressive strength by balancing the density difference [19]. When flexural test results were examined, it was found that there was a more negligible improvement in the flexural strength of fiber reinforced concrete compared to concrete without fiber addition.…”

“…According to to the researchers, the increasing fiber rate in the concrete mixtures, flexural strength and compressive strength was increased by addition of fibers to concrete. In similar studies carried out around the world, the production of M24 type PP fiber reinforced magnesium-phosphate cement composites for quick repair applications [14], dynamic properties of concrete slabs reinforced with M19 type PP fiber by 0.1% and 0.5% [15], comparison of the properties of reinforced concrete which changes depending on PP fiber dimensions [18], effects of the use of PP-Steel fiber on the hardening properties and impact resistance of concrete [19,20], usability of PP fiber with recycled aggregate 483 [21], effects of PP fibers on the properties of reinforced concrete structures [22][23][24], effects of inorganic additives and surface modified PP fibers on rheological, thermal, thermomechanical and mechanical properties of concrete [25], effect of PP fibers on the burning property of concrete [26], determination of an ideal PP fiber ratio for improving compressive and flexural strength of concrete [27], statistical analysis of PP fiber reinforced concrete [28], reinforcing of concrete and cement mixtures with M5, M10, M15, M24 type PP fibers [29] were investigated.…”

“…In the literature reviews, it was indicated by researchers that the properties of fibrous concrete significantly differed depending on fiber geometry (monofilament or film), fiber content, fiber length and diameter, tensile stress, slenderness ratio, and that impact resistances should be examined for different types of aggregate and fibers [1,3,13,15,29,30]. In the literature, it was determined that the studies carried out with M12-type fibers were limited [18,20,23,26], fibers with a diameter of 18 µ [19,26] and 22 µ [20,23] were mostly studied, and there was no study on the effect of intensely used M12 type PP fiber with a diameter of 32 µ [3,12] on the mechanical properties of concrete. In this study, it was aimed to examine changes occurring in the mechanical properties and micro-structures of concrete by adding M12 monofilament type PP fiber with a diameter of 32 µ and a density of 0.905 g/cm 3 to concrete at different ratios, and to determine the ideal microstructures, and to determine the ideal amount of fiber to increase the impact resistance of concrete when M12 type PP fiber with a diameter of 32 µ was used.…”

Behavior of high performance artificial lightweight aggregate concrete reinforced with hybrid fibers

“…Lightweight aggregate concrete containing mono and triple fiber showed higher splitting and flexural strengths when compared with double hybrid fibers. Widodo et al [8] examined the effect of hybrid polypropylene-steel fiber on properties of lightweight concrete made of pumice breccia as coarse aggregate. Monofilament Polypropylene with 12 mm length and 18 μm diameter and macro hooked end steel fiber with 60 mm length and 0.75mm diameter were used.…”

Evaluating Mechanical Properties of Macro-Synthetic Fiber-Reinforced Concrete with Various Types and Contents

“…Prathap and Siva Reddy [19] conducted an experiment on the elastic modulus by changing the steel fiber content in fiber-reinforced concrete and reported that by increasing the fiber content, the elastic modulus would be increased. Widodo et al [20] investigated the effect of adding the compound (polypropylene and steel) fibers on mechanical properties of concrete and reported that adding the compound fibers would lead to the increase in compressive strength, elastic modulus, tensile strength, and modulus of rupture by 22, 24, 222, and 187%, respectively.…”