Concrete Beams Strengthened with Jute Fibers

Nowadays, the reinforcement of concrete with natural fibers can consider being an effectual scheme to achieve the global demand for sustainable development. Due to sustainability, bio degradability, and environmental friendly, natural fibers are preferred as compared to synthetic fibers. The present study investigated the effect of width and thickness of jute fiber strips on the mechanical properties of reinforced concrete beams (RC beams). The experimental program consisted testing of twenty-four RC beams (150*150*1000 mm) comprised of four groups. The first group consisted of three reference RC beams, the second group consisted of three RC beams strengthened longitudinally with carbon fiber strip (CFRP) of 15 cm width, the third group included nine RC beams strengthened longitudinally with one layer of jute fiber strips (JFRP) having variable width, 5, 10, and 15 cm, and lastly the fourth group which was same as the third group except using double layer of jute fiber strips. Generally, the results showed that toughness, ultimate flexural strength, and load carrying capacity of RC beams strengthened with JFRP were increased with the increase of the strip width and thickness. On the other hand, ductility and stiffness were decreased with the increase of the strip width. Test results showed that load carrying capacity was improved by 5.56 and 11.1% for one layer of jute fiber strips of 5 and 15 cm width respectively as compared with the reference specimens. On the other hand, the load carrying capacity was improved by 3.95 and 8.75 % for two layers of jute fiber strips of 10 and 15 cm width respectively as compared with the one layer strengthened specimens. Concerning the CFRP strengthening, the load carrying capacity was improved by 77.76% as compared with the reference specimens.

Mechanical performance of fibers in hot mix asphalt: a review

The use of fibers in hot mix asphalt (HMA) has become a much more attractive alternative for the con-struction of road pavements. Numerous studies have shown that the incorporation of fibers in the mix-ture improves fatigue resistance, permanent deformation and stiffness. The aim of this paper is to presenta review of the mechanical impact of fibers in HMA by analyzing their reinforcement effect in a qualita-tive and quantitative manner. Fiber properties and characterization tests on fiber-modified bitumen arediscussed. Quantities, blending procedures and performance of bituminous mixtures with different typesof fibers are presented. Results of mechanical improvement are displayed. Based on the current researchresults, depending on the properties and the type of mixture in which they are used, each type of fiberseems to improve certain parameters more than others. Coconut fibers and waste fibers are describedas environmentally friendly alternatives

Brittle Materials in Mechanical Extremes

The goal of the Special Issue “Brittle Materials in Mechanical Extremes” is to spark a discussion of the analogies and the differences between different brittle materials, such as ceramics and concrete. The contributions to the Issue span from construction materials (asphalt and concrete) to structural ceramics to ice. Data reported in the Issue were obtained by advanced microstructural techniques (microscopy, 3D imaging, etc.) and linked to mechanical properties (and their changes as a function of aging, composition, etc.). The description of the mechanical behavior of brittle materials under operational loads, for instance, concrete and ceramics under very high temperatures, offers an unconventional viewpoint on the behavior of such materials. While it is by no means exhaustive, this Special Issue paves the road for the fundamental understanding and further development of materials

Effect of using Fibre on the Durability of Asphalt Pavement

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

Achievements and Prospects of Functional Pavement

In order to further promote the development of functional pavement technology, a Special Issue entitled “Achievements and Prospects of Functional Pavement” has been proposed by a group of guest editors. To achieve this objective, the articles included in this Special Issue are related to different aspects of functional pavements, including green roads to decrease carbon emissions, noise, and pollution, safety pavements to increase skid resistance through water drainage and snow removal, intelligent roads for monitoring, power generation, temperature control and management, and durable roads to increase service life with new theories, new design methods, and prediction models, as highlighted in this editorial

International Conference on Civil Infrastructure and Construction (CIC 2020)

This is the proceedings of the CIC 2020 Conference, which was held under the patronage of His Excellency Sheikh Khalid bin Khalifa bin Abdulaziz Al Thani in Doha, Qatar from 2 to 5 February 2020. The goal of the conference was to provide a platform to discuss next-generation infrastructure and its construction among key players such as researchers, industry professionals and leaders, local government agencies, clients, construction contractors and policymakers. The conference gathered industry and academia to disseminate their research and field experiences in multiple areas of civil engineering. It was also a unique opportunity for companies and organizations to show the most recent advances in the field of civil infrastructure and construction. The conference covered a wide range of timely topics that address the needs of the construction industry all over the world and particularly in Qatar. All papers were peer reviewed by experts in their field and edited for publication. The conference accepted a total number of 127 papers submitted by authors from five different continents under the following four themes: Theme 1: Construction Management and Process Theme 2: Materials and Transportation Engineering Theme 3: Geotechnical, Environmental, and Geo-environmental Engineering Theme 4: Sustainability, Renovation, and Monitoring of Civil InfrastructureThe list of the Sponsors are listed at page 1

Bitumen and Its Modifier for Use in Pavement Engineering

This chapter focuses on bitumen specifically. This chapter consists of several parts that can be mentioned, including the history of the appearance of bitumen and the types of constituent elements, as well as its mechanical properties and chemical structure and its thermal sensitivity. In all parts, the effects of bitumen on asphalt are discussed. In the following sections, the bitumen modification mechanism, polymer modifiers, and their behavior on the bitumen resistance to asphalt failures are also discussed. This chapter is very suitable for students and researchers interested in improving polymerization asphalt and bitumen and will help them to carry out research and concepts

Innovative Materials for Construction

Most of the typical materials employed in today’s constructions present limitations, especially concerning their durability, in either common or severe environmental conditions, and their impact on the environment. In response to these issues, academic and industrial efforts around the world have been devoted to developing new smart materials that can provide efficient alternatives, improve the energy efficiency of buildings, or can upgrade, repair, or protect existing infrastructures. Different and wide technological innovations are, therefore, quickly fostering advancements in the field of construction materials. A new generation of materials (bricks, cement, coatings, concrete, FRP, glass, masonry, mortars, nano-materials, PCM, polymers, steel, wood, etc.) is gaining a prominent position in modern building technology, since they can overcome various limits and flaws of conventional materials employed in constructions, without neglecting the smart applications of pioneering materials in ancient constructions and historic buildings. Even though the adoption of innovative materials in the construction field has been a successful route in achieving enhanced performance, or even new and unexpected characteristics, some issues have not been completely solved. On top of them, the cost/performance ratio of novel solutions, since their introduction must be convenient, without compromising quality. Other concerns are related to their sustainability, with eco-friendly options, possibly exploiting recycled materials or by-products from other productions, being the most desirable solution. Finally, the use of materials or systems that are unconventional in this field raises the need to update or develop new specifications and standards. This special issue aims at providing a platform for discussing open issues, challenges, and achievements related to innovative materials proposed for the construction industry

INTEGRATED COMPUTATIONAL AND EXPERIMENTAL EVALUATION OF ELECTROMAGNETIC ENERGY-INDUCED SELF-HEALING PERFORMANCE OF ASPHALT COMPOSITES

The objective of this doctoral research is to investigate the electromagnetic energy induced self-healing effect of modified asphalt mixture material by developing computational and experimental characterization tools. More than 90% of the pavements in United States are constructed by asphalt mixture. The durability of pavement decreased by distresses has significant impact on maintenance costs. The asphalt mixture has self-healing capability because the asphalt could flow and fill the microcracks if enough external energy can be transmitted to the asphalt mixture system. However, the self-healing capability of asphalt is limited based on the climatic condition and traffic volume. Therefore, it is necessary that a new method named electromagnetic-induced healing needs to be used to accelerate the self-healing process of the asphalt mixture. In this research, different materials were added into asphalt to produce the modified asphalt binder samples and modified asphalt mixture samples, including steel wool, carbon fiber, graphite flake and exfoliated graphite nanoplatelets (xGNP). Some relative asphalt binder tests were conducted to evaluate the performance of modified asphalt, including rotational viscosity, light absorbance, aging and thermal conductivity. Some other tests were employed to evaluate the performance of the asphalt mixture, including disk-shaped compact tension test, dynamic modulus test, and rutting test. Three EM-induced healing approaches were utilized to investigate the induction healing effect of the asphalt mixture material, including the longwave radiation, visible/near-infrared light and microwave healing, respectively. In addition, a multi-phase triangle-shaped finite element bilinear cohesive zone model (CZM) was developed to simulate the fracture behavior of the original and strength recovered asphalt mixture samples during the cyclic fracture-induction healing tests. The digital image correlation (DIC) method was used to analyze the crack displacement variation of the fracture samples. The relative strain ratio was incorporated to determine the recovered fracture energy for the simulation model. The experimental results indicated that three added materials all could increase the healing effect of the asphalt mixture samples. The favorable numerical results compared with the experimental results indicated that the finite element bilinear CZM with defined crack path can be used to predict the recovered fracture strength after fracture-induction healing cycles