Properties of Coir Fibre and Kenaf Fibre Modified Asphalt Mixes

ARO-THE SCIENTIFIC JOURNAL OF KOYA UNIVERSITY

Cracking in the flexible pavement is a serious problem that reduces the service life of the roads pavement unless they are treated with great care. Since flexible pavement is very weaker in tension than in compression, it is usually necessary to consider the tensile stresses and some type of additives to improve asphaltpavement performance, and one of the most effective ways of improving asphalt pavement performance is to reinforce asphalt mixtures by incorporating natural fibers. The main objective of this study is to use palm fiber, which is locally available, in hot mix asphalt mixtures. To achieve this objective, the Marshall test and indirect tensile strength test were conducted on four asphalt mixtures with different types of natural fibers (Coconut, Corn, Palm, and Sisal), added in varying percentages 0.1, 0.2, 0.3, 0.4, and 0.5% and different lengths of fiber 0.5, 1, 1.5, and 2 cm. Based on the analyzed results, it can be concluded that the use of palm fiber increased the Ma...

IOP Conference Series: Materials Science and Engineering

The enhancement of mechanical properties and long term performance of hot mix asphalt (HMA) should be considered as a goal in order to achieve a transport infrastructure really sustainable. However, this issue becomes a difficult task, if conventional HMA are used. In fact, performance of conventional HMA, usually presents poor long term performance and functional distresses related to high and low temperatures, which in turn implies higher maintenance costs and superior carbon footprints. To overcome this weaken, bitumen industry has been developing new polymer modifiers, additives to improve HMA behaviour. One of the techniques most used in developed countries to enhance HMA behaviour is the use of modified bitumen. Modifying the bitumen, and then producing modified HMA requires specific equipment and facilities that may be time-consuming, expensive and hard to manage. For instance, to warranty a successful modifying process, storage and handling of the modified bitumen are issues very complex to handle. On the other hand, producing a polymer modified HMA by adding polymers and additives directly during the bitumen/aggregate mixing process may offer very interesting advantages since the economical, production and sustainability standpoint. This paper aimed to determine the feasibility of the incorporation of fibres and plastomeric polymers into different types of HMA by means of the "dry process" (to add polymers during the mixing of aggregate and bitumen in the HMA plant) to produce polymer modified mixes. Thus, laboratory tests including Marshall Stability, Indirect Tensile Stiffness Modulus, repeated load test and Indirect Tensile Strength test were performed to assess the effect of the inclusion of fibres and plastomeric polymers on mechanical and volumetric properties of selected mixes. Results showed that the modification of bituminous mixtures following the "dry process" could be used to improve the performance and long term properties of HMA.

Civil Engineering and Architecture, 2023

With large natural asphalt deposit sits in its soils, Indonesia should not worry regarding the availability of the pavement material in the near future. However, this natural asphalt, called Buton Asphalt, has some deficiency in terms of its ability to sustain crack. Therefore, it should be modified with material resisted to cracking. One of such materials is palm sugar fiber. The objective of this research was to investigate the effect of adding palm sugar fiber to the hot mix Buton-asphalt mixture based on the Marshall characteristics. The sugar palm fiber was varied at 0.2-0.4% of the mixture weight at 0.5-1.5cm fiber length. The mixture preparation conformed to the 2018 Bina Marga Specifications. The result showed that the mixture's optimal sugar palm fiber content was 0.2% of the mixture weight with a length of 0.5 cm. Adding sugar palm fiber increased Marshall stability up to 3.11% and Marshall Quotient by 15.56%. VMA and VIM also increased to 7.97% and 33.76%, respectively. The Marshall flow, however, decreased to 13.07%. The result indicates that adding sugar palm fiber to the mixture improved the mixture's performance. Therefore, for future use, it is recommended to add this fiber as the modifier. As for future research, other types of fiber such as coconut fiber should also be investigated for its potential use in Buton Asphalt mix.

Using of fibers is not a new phenomenon; the technique of fiber-reinforced bitumen began as early as 1950. Fiber reinforcement refers to incorporating materials with desired properties within some other materials lacking those properties [1]. The principal function of the fiber is to provide additional tensile strength in the resulting composite. This could increase the amount of strain absorbed during the fatigue and fracture process of the mixture [2]. Fibers are sometimes added to stabilize the binder during mixing and placement. An additional benefit of using fibers is that fibers have been shown to allow increased asphalt binder contents and thus increase film thicknesses thereby increasing durability [5]. Asphalt cement modifiers have been used in pavement technology to enhance pavement performance and reduce different types of pavement distress, of which, rutting, low temperature cracking, fatigue cracking, stripping, and hardening are the most common failure. The present project investigate the usability of mineral fibers in order to resist the stresses occurring at the surface layer of pavement, which are directly subjected to the traffic effects. For this purpose four different types of mineral fibers (steel , aluminium , copper and tin), four different fiber rates (1% , 1.5% , 2% , 2.5%) by total weight of mixture, with varying lengths of mineral fiber (0.5 ,1.0 ,1.5 ,2.0) cm, and four different thickness (0.2 , 0.4 , 0.7 , 0.9) mm were used in this study. All specimens have been tested by Marshall method. The results indicated that adding (1.5%) of the copper fiber by the total weight of mixture, with (0.5 cm) length and (0.4 mm) thickness increase Marshall stability by (34%) as compared with the conventional mix.

American Journal of Science and Learning for Development, 2023

In this study, the researchers investigated the effects of using a locally available fiber called Sisal fiber as a stabilizer in Stone Matrix Asphalt (SMA) and as an additive in Bituminous Concrete (BC). The composition of a bituminous mixture typically includes coarse aggregate, fine aggregate, filler, and binder. Hot Mix Asphalt (HMA) refers to a bituminous mixture where all the constituents are mixed, placed, and compacted at high temperatures. SMA is a type of HMA that is gap graded, while BC is a Dense Graded mix (DGM) also known as Bituminous Concrete. SMA requires stabilizing additives such as cellulose fibers, mineral fibers, or polymers to prevent the drainage of the mix. The researchers aimed to study the impact of adding Sisal fiber, a naturally available fiber, as a stabilizer in SMA and as an additive in BC. To prepare the mixes, the researchers followed the aggregate gradation specified by MORTH (Ministry of Road Transport and Highways). The binder content was varied from 4% to 7%, and the fiber content ranged from 0% to a maximum of 0.5% of the total mix. In the preliminary study, fly ash was found to yield satisfactory Marshall Properties, so it was used in subsequent mixes. Using the Marshall Procedure, the Optimum Fiber Content (OFC) for both BC and SMA mixes was determined to be 0.3%. Similarly, the Optimum Binder Content (OBC) for BC and SMA was found to be 5% and 5.2% respectively. The BC and SMA mixes prepared at these optimum levels were then subjected to various performance tests, including Drain Down test, Static Indirect Tensile Strength test, and Static Creep test, to evaluate the effects of fiber addition on mix performance. The study concluded that the addition of Sisal fiber improves the mix properties, such as Marshall Stability, Drain Down characteristics, and indirect tensile strength, for both BC and SMA mixes. It was also observed that SMA performed better than BC in terms of indirect tensile strength and creep characteristics.

Construction and Building Materials

This research aims to examine the impact of using natural and synthetic fibres as reinforcing materials, on the mechanical properties and water susceptibility of cold mix asphalt (CMA) including indirect tensile stiffness and resistance to rutting, cracking and moisture damage. Four different types of fibres were used: glass as a synthetic fibre, and hemp, jute and coir as natural fibres. Various samples of CMA, with and without fibres, were fabricated and tested. Traditional hot mix asphalt (HMA) was also used for comparison. The results indicate a significant improvement in the indirect tensile stiffness modulus, for all fibre-reinforced CMA mixtures, over different curing times. The improved tensile behaviour represents a substantial contribution towards slowing crack propagation in bituminous mixtures, while scanning electron microscopy analysis confirmed the fibre shape and surface roughness characteristics. The improved performance of the reinforced mixtures with both natural and synthetic fibres, facilitated a substantially lower permanent deformation than traditional hot and cold mixtures at two different temperatures (45 and 60°C). When using glass and hemp fibres as reinforcing materials, there was 2 a significant improvement in CMA in terms of water sensitivity. Resistance to surface cracking was also improved when fibres were incorporated. Based on the test results, 0.35% fibre content by mass of dry aggregate and 14mm fibre length are recommended to achieve the optimum performance output for indirect tensile stiffness.

Using the fibre additives with a uniform distribution in asphaltic concrete mixture is a well-known technique for improving the mechanical properties and durability of asphalt pavement. The purpose of this study is to investigate the effect of preparing fibre and production of the properties of bitumen and asphalt concrete mixture. In this study, a dense-graded aggregation, mineral fibres (asbestos) and synthetic fibres (polyester and nylon) were used. Laboratory studies were done by comparing different rheological properties, mechanical and moisture susceptibility of mixtures of fibres. Results of the penetration and softening point on mixtures of bitumen – fibre show that fibres improve the mixed rheological properties and stiffening effect of fibre properties. The results of Marshall Tests indicate that adding fibres reduces the strength in Marshall and results in the slight increase in the percentage of optimum bitumen content and asphalt percentage of air voids in comparison with typical fibre. The results of the indirect tensile tests showed that the addition of fibres, depending on the percentage of fibres significantly improves the durability of the mixture.

2024

showed that the optimum properties of the HMA were reached by adding 0.4% CF to the HMA. Marshall stability was increased by 48%, the flow was decreased by 23%, and in addition, rut depth was reduced by 50%. The unit weight and the percentage of air voids in the mix were maintained and, along with other mix properties, are preserved within acceptable limits. Moreover, the indirect tensile strength has increased by 88.6%. Furthermore, moisture susceptibility reached 88%. Therefore, the addition of 0.4% CFs improved the performance of HMA at a high temperature of 60°C, which is close to the paving temperature in Iraq, by reducing the rutting of the asphalt mixture, which is considered the most dangerous tiling problem in Iraq. By improving the performance characteristics of asphalt mixture, the durability of the pavement will increase, and the riding will be more comfortable.

Stone Matrix Asphalt (SMA) is a gap graded mix which consists of 70−80% coarse aggregate, 8−12% filler, 6.0−7.0% binder, and 0.3 percent fiber. SMA was first used in Europe and later, other countries had adopted the use of SMA for pavements like Germany and US etc. The problem with SMA is drain down during transportation and laying. To reduce the draindown of SMA, stabilizing additives like chemical and natural additives are used. In this present study, the fibers used for Grade-I (MORTH) and Grade-II (IRC) mixes. This research is to check the feasibility of fibers as stabilizing additives in which the flow values and stability values were analyzed by performing Marshall Stability test. Various percentages such as 5.5%, 6%, 6.5% and 7% of bitumen are selected for this study. Draindown test is initially performed to find the optimum fibre content and finally to find the optimum bitumen content. The test results for both grade-1 and grade-2 mixes by the use of fibres reduced the drain down value and maximum stability value for both grade-1 and grade-2 mixes is obtained for coir fibre when compared with pineapple fibre.