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Ongoing studies show that an effective demand for using natural fibers as a substitution of an artificial fiber in fiber-reinforced composites formation has increased their applicability in an industrial area worldwide. The hydrophobic nature of natural fiber makes week adhesion among the cellulose fiber and matrix components; these problems are usually encountered in fiber-reinforced composites production. To overcome such a limitation of a cellulose fiber, specific physical and chemical treatment strategies were advised by researchers around the world for surface modification of natural cellulose fibers. One of the most basic and efficient surface modification approaches adopted today by the researchers was alkali treatment, widely used in natural fiber composites formation. This technique effectively improved the Mechanical property of natural cellulose fiber, such as tensile strength and flexural properties, while the impact strength result was reduced.

Currently, researchers are more focusing on eco-friendly materials, sustainability, and low consumption of energy during the stage of handling, low initial cost, have appropriate mechanical properties and biodegradable and less susceptible to health hazards are the main challenge facing in the present day across the world especially to developing new materials that would improve the industrial supplies for making lightweight materials. Therefore; natural cellulosic fiber one, of effective strategies to substitute artificial fibers for its own benefits when compared and mainly concentrating to reinforce polymer matrices by natural cellulosic fiber due to their decomposable characteristic in nature. This an overview mainly discussed on commonly available natural fiber property such as physical property, chemical composition analysis, surface morphology analysis such as thermal stability analysis (TGA), Fourier Transform Infrared (FTIR) analysis and Scanning Electron Microscopy (SEM) to be adopted in order to characterized natural fiber and impact of treating natural fibers by appropriate chemical on certain properties was discussed by supporting literature. In addition to this the significance of characterization of natural fiber briefly discussed and this an overview will helps other researcher’s source for natural fiber composite studies in future studies.

Concrete crack is one of the main problems observed in concrete technology due to drying shrinkage. Incorporating fibers in concrete production is one of the mechanisms implemented to mitigate cracks. Nowadays, investigators concentrate on different techniques to replace human-made fiber with existing natural fibers for fiber-reinforced composite material. Utilization of natural fiber has an initiation for the development of eco-friendly materials by reducing damages caused by human-made materials and saving nonrenewable resources. Natural fibers are readily and abundantly available, sustainable, and biodegradable, with low cost and low density, and have superior specific properties. Nevertheless, there are some limitations of natural fiber compared to human-made fiber. Consequently, significant energy was applied to alter natural fiber’s surface and morphology using physical, chemical, and biological treatment techniques to overcome the limitation. The primary intention of surface treatment is to modify the bond between the fiber surface and the polymer matrix. However, based on this literature review, there were no specific treatment techniques to be followed to select the best one from the others as criteria. It should include all parameters to consider starting from the stage from the cradle to the grave, cost of chemicals, transportation, and labors, including energy consumption and effluent energy. Additionally, their environmental effect also investigated in detail to compare each other.

An advanced design classification system for bicycle paths, based on geometric features and force equilibrium, can pave the way for improved bicycle safety, accident prevention and the development of design guidelines. A design and classification system does exist for bicycle paths, but the number of accidents has led to ambivalence about its validity and effectiveness. In addition, a universally accepted classification system has not yet been approved or adopted. This paper presents a unique set of design parameters, analytically developed based on formulas that consider the physical characteristics and dimensions of individual bicycles. The proposed design system is based on theoretical trigonometric derivations. The model was validated with the real-world geometry of the transportation infrastructure of the city of Antwerp, Belgium. The conclusions of this study are useful for evaluating the effectiveness of bicycle paths during the design stage without the necessity for real-world experiments. The results will thus be valuable for stakeholders working on policy frameworks, bicycle safety and riding comfort.

Continuously reinforced concrete pavement (CRCP) is characterized by the absence of transverse contraction joints and the presence of longitudinal and transverse reinforcement. The continuous longitudinal reinforcement holds the transverse cracks, caused by the longitudinal shrinkage of concrete, tightly together and thus provides long term performance with minimal maintenance cost. Field investigations on recently constructed CRCP's in Flanders region of Belgium indicated horizontal cracking in the vicinity of the longitudinal reinforcement under the transverse cracks which eventually causes the punch-out distress at the edge of the pavement slab. This paper shows the results of a finite element (FE) study to investigate the effect of varying longitudinal reinforcement on the risk of horizontal cracking in CRCP under typical Flanders conditions. For this purpose, a (3D) FE model of CRCP is developed using a FE package Diana 10.2. The varying longitudinal reinforcement with a most narrow spacing of 125mm in the outer region of the pavement slab is applied while keeping the same CRCP reinforcement ratio. A comparison is made with the conventional longitudinal reinforcement spacing (170mm). Development of concrete stress in the vicinity of the longitudinal reinforcement is plotted against the different longitudinal steel spacing. Findings show that the stress in concrete near longitudinal reinforcement is significantly reduced up to maximum 17% when the narrow spacing is used. In addition, the steel stress in the longitudinal reinforcing is reduced up to maximum 31.75% in the outer region of the pavement slab.

Since 1970, continuously reinforced concrete pavements have been used in Belgium. The standard design concept for CRCP has been modified through several changes made in the design parameters to eliminate the cluster of closely spaced crack patterns, since these crack patterns lead to the development of spalling and punch-out distresses in CRCPs. Despite adjusting the longitudinal reinforcement ratio, slab thickness, and addition of asphalt interlayer, the narrowly spaced cracks could not be effectively removed. The application of transverse partial surface saw-cuts significantly reduced the probability of randomly occurring cracks in the reconstruction project of the Motorway E313 in Herentals, Belgium. The field investigation has also indicated that the early-age crack induction in CRCP is quite susceptible to the saw-cut depth. Therefore, the present study aims to evaluate the effect of different depths and lengths of the partial surface saw-cut on the effectiveness of crack induction in CRCP under external varying temperature field. For this purpose, the FE software program DIANA 10.3 is used to develop the three dimensional finite element model of the active crack control CRCP segment. The characteristics of early-age crack induction in terms of crack initiation and crack propagation obtained from the FE model are compared and discussed concerning the field observations of the crack development on the active crack control E313 test sections. Findings indicate that the deeper saw-cut with longer cut-lengths could be a more effective attempt to induce the cracks in CRCP in desirable distributions to decrease the risk of spalling and punch-out distresses in the long-term performance of CRCP. These findings could be used as guidance to select the appropriate depth and length of saw-cut for active crack control sections of CRCP in Belgium.

The technological innovation of continuously reinforced concrete pavement (CRCP) that contains a significantly reduced amount of reinforcement and the same fundamental behavior as CRCP is called advanced reinforced concrete pavement (ARCP). This new concept of a rigid pavement structure is developed to eliminate unnecessary continuous longitudinal steel bars of CRCP by using partial length steel bars at predetermined crack locations. In Belgium, partial surface saw-cuts are used as the most effective crack induction method to eliminate the randomness in early-age crack patterns by inducing cracks at the predetermined locations of CRCP. The reinforcement layout of ARCP is designed based on the distribution of steel stress in continuous longitudinal steel bar in CRCP and the effectiveness of partial surface saw-cuts as a crack induction method. The 3D finite element (FE) model is developed to evaluate the behavior of ARCP with partial surface saw-cuts. The early-age crack characteristics in terms of crack initiation and crack propagation obtained from the FE simulation are validated with the field observations of cracking characteristics of the CRCP sections in Belgium. The finding indicates that there is fundamentally no difference in the steel stress distribution in the partial length steel bar of ARCP and continuous steel bar of CRCP. Moreover, ARCP exhibits the same cracking characteristics as CRCP even with a significantly reduced amount of continuous reinforcement.

The objective of this study is to evaluate the horizontal cracking potential in terms of vertical tensile stress development near longitudinal steel bar in the continuously reinforced concrete pavement (CRCP). For this purpose, a three-dimensional (3D) finite element (FE) model of the CRCP segment with partial surface saw-cuts has been developed using the FE tool Diana 10.3. The early-age behaviour of CRCP subjected to external varying temperature field condition has been evaluated by using the staggered structural-flow analysis. The characteristics of the early-age crack pattern in terms of crack initiation and crack propagation obtained from the FE model are compared with the field observations of cracking developments on the CRCP sections in Belgium. The FE results indicate that the vertical tensile stress in concrete near the longitudinal steel bar develops at the transverse crack interface. It translates that the horizontal crack perpendicular to the vertical concrete stress can initiate from the transverse crack depending on the magnitude of stress against developing concrete tensile strength. It has also been observed that the deeper the saw-cut, the larger the magnitude of vertical tensile stress and the higher incident of horizontal cracking. Moreover, the developed 3D FE model can be further used to optimize the early-age behaviour of CRCP in advance of costly field trials.

Currently, due to global warming, a lot of investigation and advance has been growing in the possible use of natural fibres composite universally. Scholars highly initiated the significance due to its advantage of human-made fibres, such as little ecological impact and low cost. Many studies were established to enhance the mechanical execution and uses of natural fibre in the manufacturing trade. Investigation revealed on natural fibre composites can be set into a load-bearing structural and infrastructure use. As an engineered usual material, related to human-made fibre composites, the attributes of natural fibre compounds can be oriented to attain a positive request. The common problems in operational with natural fibre compounds were excessive discrepancy and appearances. Natural fibre composites’ attributes, which have a significant level, are mostly subjective by the category of fibres, ecological circumstances also the source of cellulose fibres, and the kind of fiber treatments. As the addition of natural fibre increases in fiber-reinforced concrete production, its slump test value decreases, but it improves the mechanical property of concrete up to a certain value. Then, it starts to decline compared to the control mix design and also, the mode of failure changes from brittle to ductile with the inclusion of natural fiber. Though, cellulose fibre composites might appear as a novel substitute for a rock-solid material with their uniqueness and unevenness and substitute expensive human-made fiber composites. This assessment will deliver an overview of natural fibre mechanical performance and toughness in the concrete, one of the importance of natural fibre compared to a human-made one, and the detailed achievements on its uses supported by the literature.

The technological innovation of continuously reinforced concrete pavement (CRCP) that contains a significantly reduced amount of reinforcement and the same fundamental behaviour as CRCP is called advanced reinforced concrete pavement (ARCP). This new concept of a rigid pavement structure is developed to eliminate unnecessary continuous longitudinal steel bars of CRCP by using partial length steel bars at predetermined crack locations. In Belgium, partial surface saw-cuts are used as the most effective crack induction method to eliminate the randomness in early-age crack patterns by inducing cracks at the predetermined locations of CRCP. The reinforcement layout of ARCP is designed based on the distribution of steel stress in continuous longitudinal steel bar in CRCP and the effectiveness of partial surface saw-cuts as a crack induction method. The 3D finite element (FE) model is developed to evaluate the behaviour of ARCP with partial surface saw-cuts. The early-age crack characteristics in terms of crack initiation and crack propagation obtained from the FE simulation are validated with the field observations of cracking characteristics of the CRCP sections in Belgium. The finding indicates that ARCP exhibits the same cracking characteristics as CRCP even with a significantly reduced amount of continuous reinforcement.

Intersections are established dangerous entities of a highway system due to the challenging and unsafe roadway environment they are characterized for drivers and other road users. In efforts to improve safety, an enormous interest has been shown in developing statistical models for intersection crash prediction and explanation. The selection of an adequate form of the statistical model is of great importance for the accurate estimation of crash frequency and the correct identification of crash contributing factors. Using a six-year crash data, road infrastructure and geometric design data, and traffic flow data of urban intersections, we applied three different functional forms of negative binomial models (i.e., NB-1, NB-2, NB-P) and a generalized Poisson (GP) model to develop safety performance functions (SPF) by crash severity for signalized and unsignalized intersections. This paper presents the relationships found between the explanatory variables and the expected crash frequency. It reports the comparison of different models for total, injury & fatal, and property damage only crashes in order to obtain ones with the maximum estimation accuracy. The comparison of models was based on the goodness of fit and the prediction performance measures. The fitted models showed that the traffic flow and several variables related to road infrastructure and geometric design significantly influence the intersection crash frequency. Further, the goodness of fit and the prediction performance measures revealed that the NB-P model outperformed other models in most crash severity levels for signalized intersections. For the unsignalized intersections, the GP model was the best performing model. When only the NB models were compared, the functional form NB-P performed better than the traditional NB-1 and, more specifically, the NB-2 models. In conclusion, our findings suggest a potential improvement in the estimation accuracy of the SPFs for urban intersections by applying the NB-P and GP models.

Intersections are sites where traffic crashes are highly concentrated. This is because conflicting traffic maneuvers are highest at the intersections and, therefore, they are more prone to crash occurrence. An accurate understanding of the relationships between various geometric features, traffic flow, and crashes in the influence area of intersections, could help reduce these crashes by suggesting appropriate countermeasures. Safety performance functions are the tools to understand these relationships. In this study, we developed safety performance functions specific to Antwerp, Belgium, for urban intersections, using multiple functional forms of a Poisson-gamma framework considering total crash counts. A dataset consisting of six years (2010–2015) of intersection crashes, traffic flows (major and minor), and geometric features was created. This paper documents the development process of safety performance functions for signalized and un-signalized intersections, connecting roadway geometry and traffic characteristics to intersection related crashes and, thus, estimating the impact of predictor variables on the crash occurrence, so as to facilitate the safe design. The findings indicate several road geometric and traffic variables that have a significant impact on crashes at urban intersections. The results revealed that to improve intersection safety, enough attention must be paid to the number of through lanes of a minor approach, intersection skewness, size, and presence of crosswalks on the approach roads. Furthermore, it was found that an early inquiry into the model’s functional form could result in more accurate estimates of crash frequency.

Risk perception influences cycling attributes toward its adoption. Researchers are investigating attributes associated with risk formation. In this study, various attributes were selected which influence the user&rsquo, s formation of risk perception. For this purpose, an online questionnaire survey was conducted in Flanders, among all segments of the population (N = 774). Participants were asked questions for attributes relating to risk formation. Results suggested that risk formation among users evolves around tangible to non-tangible attributes. The spectrum of risk perception was developed which visualizes risk evolution, considering various attributes. Surprisingly, elements such as &ldquo, comfort&rdquo, surface evenness, and policies were rated as being neutral. Infrastructure and the presence of opposite road users tend to be foreseen as critical factors for risk formation. Risk perception varies depending upon psychometric paradigm shifts, such as dread and unknown risk. This strange notion is considered to lie in a space between dread and unknown risk. This explains the difference in risk perception, knowingly or not knowingly (subconsciously), yet expressing cognitively and evolving inside. This is an interesting finding, but reasons behind such a motive need to be explained. A possible explanation behind such behavior is that people tend to change their responses due to knowledge acquisition during the survey.

Continuously reinforced concrete pavements (CRCP) are frequently used in Belgium on roads having heavy traffic because they have a better long-term performance and require low maintenance. Free cracking is allowed in CRCP but the cracking pattern is controlled by the continuously longitudinal reinforcement. The problem is that in reality the crack pattern is not as desired. Distances between cracks are sometimes smaller, creating clusters of cracks. These clustered cracks can evolve over time, and, after many heavy axle load passages, lead to destructive punch-outs.

In order to increase the structural performance, various techniques are being evaluated, tested and adopted. Structures exposed to adverse environmental conditions, are facing issues i.e. lifespan reduction and pre-mature failure. World-wide polyester resin is considered to be applied for re-novation, repair, especially for structural elements which are facing environmental degradation. This manuscript evaluates the quantitative performance of resin as a coating agent on mortar, under different controlled conditions. The experiment involved casting of specimens, coating 1–3 layers polyester resin on samples, exposure to environmental conditions and water. Compressive strength provide evidence that resin coats increased compressive strength of cubes by 69%. Whilst significant water absorption reduction was also noted which is proportional to number of coats. Univariate general linear model were evaluated by with respect to various parameters on the two conditions i.e. ambient environment and exposure to water. This study concludes that polyester resin may be used in primary structural element members, which are exposed to different environmental scenarios.

The Flanders motorway network, about 900 km, was constructed many decades ago. This means that short term reconstruction is unavoidable. In order to facilitate the choice of pavement for the reconstruction of the network, some recommendations are made by the Flemish Agency for Roads and Traffic. For motorway (re)construction there are several pavement possibilities: asphalt pavements, single layered continuously reinforced concrete pavement (CRCP), double layered CRCP, composite pavement (concrete base layer + asphalt top layer), thin asphalt top layers, to name a few. Besides acoustic performance, many other parameters (durability, maintenance, cost..) play a role in the selection of the type of pavement. The most acoustically efficient option is not always the most durable option, in terms of Life Cycle Cost (LCC) and an LCC-analysis can prove that statement easily. For which motorway sections that need to take the acoustic performance parameter into account, where a low noise pavement is needed can have created a criterion. This criterion takes into account the many residential areas around the road and can identify road segments on which a quieter pavement is preferred. The starting point for the criterion is to determine the number of homes within a certain distance from the road section. This paper describes the theoretical background and calculation method of the criterion for choosing low noise pavements, as well as the results of the study for the Flemish motorway network.

Cycling as work-school activity is considered significant urban mobility option among Flemish road users. New provisions introduced by Flemish govt needs to be investigated, and what are its possible influence and perception among weak road users. Hence stated preference survey was conducted among 817 Flemish weak road users who mostly use Urban regions i.e. Antwerp, Ghent and their respective suburban periphery. This study identifies cyclists into four categories i.e. Active Cyclists, Potential Cyclists, Pro Car, Pro Public transport or walk. The study aims at improving cycling facility for a safer perception for cyclists in order to alleviate active urban mobility options. The survey includes attitudes towards, effective, coherent infrastructure, risk perception, motivation/barriers to cycle, and different cycling conditions one faces on daily routine basis. This manuscript uses hybrid choice modelling to investigate user preferences. Explanatory variables such as income, age, education level, dangerous intersections, coherent and effective infrastructure are found significant confirming earlier literature. Whereas policies which promote cycling are found not to have a significant influence except tax benefits. Overall the respondents were satisfied with new mobility regulations but showed desire of further improvement.