Highlights Multiple safety performance functions (SPFs) by crash severity are developed for urban intersections  Various functional forms of the negative binomial (NB) regression and a generalized Poisson (GP) regression model are applied to develop the SPFs  All the NB models and a GP model show promising results when estimating the SPFs  On the basis of goodness of fit and predictive performance measures, the developed models are compared to choose a better model  The performance of the NB-P model is better than the competing models for signalized intersections while the GP model outperforms other models for unsignalized intersections

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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.

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’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 “comfort”, 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.

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.

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.

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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. To obtain a uniform crack pattern, the active crack control technique tries to force the cracks to originate in the young concrete at regular distances, perpendicular to the axis of the road. This is done by making some saw cuts in the new pavement, within 24 hours after placement, along the side of the CRCP slab. This research study tries to find the optimal dimensions of the saw cuts which result into a uniform crack pattern. To do this, a numerical 2D model of a road segment is made with the finite element program Samcef Field. The length between the notches (= saw cuts) and the width and depth of the saw cuts are varied and deformations and stresses in the concrete and reinforcement are compared. The same is done for a 3D model which is generated based on the 2D model. The results from the parameter study show that the dimensions of the active crack control technique applied nowadays, i.e. saw cuts of 40 cm long, 4 cm deep, every 1.20 m, works properly.