A Study On the Effectiveness of Rolling Barrier System at Straight Road and Curved Road: A Review

The rolling barrier system is part of the road safety infrastructure that is used to improve and maintain road safety. It is also possible to overcome and reduce the number of crashes. A rolling barrier is a type of safety device that not only absorbs but also converts shock energy into rotational energy, thereby preventing fatal accidents for drivers and passengers. A rolling barrier should be installed in areas where vehicles are frequently collided. By absorbing shock energy, a rolling barrier will safely guide a vehicle back to the road or stopped the vehicle. This study was built on the findings of a previous study to determine the effectiveness of a rolling barrier system for use on both straight and curved roads. This research focuses on a new invention, the rolling barrier system, as opposed to the traditional barrier, in order to learn more about its mechanism and function. The study's scope was limited to focusing on the implementation of the rolling barrier system on straight and curved roads. According to the previous study, straight and curved roads have the highest incident rates compared to other types of roads. The Rolling Barrier System was strategically installed in three high-risk areas with a high incidence of fatal traffic incidents. The three high-risk road locations that require additional safety are straight roads, curving roads, and hilly roads, which are the most important locations to place Rolling Barrier Systems in order to decrease high-risk accidents and fatalities while also improving road safety. There are four types of roads that are appropriate for implementing a Rolling Barrier System. The Rolling Barrier types are straight roadside Rolling Barriers, curved roadside Rolling Barriers, steep roadside Rolling Barriers, and median Rolling Barriers

A Study On the Effectiveness of Rolling Barrier System at Straight Road and Curved Road: A Review

The rolling barrier system is part of the road safety infrastructure that is used to improve and maintain road safety. It is also possible to overcome and reduce the number of crashes. A rolling barrier is a type of safety device that not only absorbs but also converts shock energy into rotational energy, thereby preventing fatal accidents for drivers and passengers. A rolling barrier should be installed in areas where vehicles are frequently collided. By absorbing shock energy, a rolling barrier will safely guide a vehicle back to the road or stopped the vehicle. This study was built on the findings of a previous study to determine the effectiveness of a rolling barrier system for use on both straight and curved roads. This research focuses on a new invention, the rolling barrier system, as opposed to the traditional barrier, in order to learn more about its mechanism and function. The study's scope was limited to focusing on the implementation of the rolling barrier system on straight and curved roads. According to the previous study, straight and curved roads have the highest incident rates compared to other types of roads. The Rolling Barrier System was strategically installed in three high-risk areas with a high incidence of fatal traffic incidents. The three high-risk road locations that require additional safety are straight roads, curving roads, and hilly roads, which are the most important locations to place Rolling Barrier Systems in order to decrease high-risk accidents and fatalities while also improving road safety. There are four types of roads that are appropriate for implementing a Rolling Barrier System. The Rolling Barrier types are straight roadside Rolling Barriers, curved roadside Rolling Barriers, steep roadside Rolling Barriers, and median Rolling Barriers

Relationship Between Rheological Properties of Nano Polymer Modified Asphalt Binder and Permanent Deformation of Asphalt Mixture

Asphalt binder plays an important part in determining many aspects of road performance. However, the rheological properties of asphalt binder are very complex and the parameters depend purely on the viscosity, various loading time and temperature. Therefore, relationship study on asphalt binder rheological properties and asphalt mixture is vital to predict the performance of the mixture. This paper evaluates the relationship between rheological asphalt binder and asphalt mixture performance containing nanopolymer modified binder. Five sets of asphalt binder rheology were tested to determine their viscosity, effect of short term and long-term aging using the dynamic shear rheometer (DSR). The asphalt mixtures performance test was then conducted to evaluate the permanent deformation of the mix. Findings from this study indicate that the rheological properties of asphalt binder acts as indicator for the asphalt mixture performance. The G*/sin δ and viscosity of the asphalt binder significantly agree with the resilient modulus and rut depth results obtained.   The dependent (resilient modulus at 40oC and rut depth) and dependent (G*/sin δ and viscosity) variables show that these variables significantly affects each other. An effective prediction models can also be developed according to predicted and measured permanent deformation values

Cold in-place recycling for flexible pavements

CIPR is an economical and environmentally sound alternative to conventional rehabilitation methods such as structural overlay or reconstruction. The reuse of existing pavement materials is a sustainable approach to pavement rehabilitation as new materials are conserved. Its use in Malaysia is expected to increase in the future as more pavement rehabilitation works instead of new roads construction will be carried out to preserve the integrity of the pavement structure and to extend the pavement life. However, an adequate understanding of the CIPR process, its suitability and limitations are essential for the correct pavement candidate to be chosen, for the works to be carried out successfully and for the pavement to perform satisfactorily

Heavy goods vehicle: review of studies involving accident factors

The use of heavy goods vehicles (HGV) has grown locally and globally. In this regard, every road user faces a high accident risk and is susceptible to traffic-related injuries and deaths. There is a substantial focus on law enforcement to prevent overloading, speeding, and illegal substance use among drivers. Nonetheless, evidence about the complex causes of HGV accidents is still scarce. Thus, this paper aims to outline the literature related to HGV study and examine factors of HGV accidents. Several factors that significantly contribute to accidents have been identified in the literature review. The study has established three main HGV accident factors with 15 sub-HGV accident factors. The Human Factor was the most dominant, while the Vehicle Factor was the least acclaimed HGV accident factor. The review also found several areas for further empirical improvements by including diverse data sources, a more extensive database, and more advanced data analysis. Moreover, technology advancements are required to capture more detailed and richer data for future studies on HGV. Future studies related to HGV accidents are essential in reducing the fatality rate in line with the Sustainable Development Goals (SDG) Goal 3 target 6, which reduces the number of individuals killed or wounded in vehicle accidents worldwide

Prediction Model of the Coring Asphalt Pavement Performance through Response Surface Methodology

Pavement evaluations provide crucial information regarding the performance and service life of asphalt concrete (HMA). They examine the structure of an existing pavement before deciding on different maintenance alternatives. The Klang Valley, as part of one of the developing areas in the state of Selangor, generates a high volume of traffic every day due to the increasing number of vehicles crossing the area. Every day, the impact of axle loads caused by vehicles has a negative impact on flexible pavement, resulting in road deterioration due to extreme distress. Pothole failures are one of the most common causes of distress. Five research areas in the Klang Valley area that have deteriorated owing to pothole failures were chosen as case studies. The objective of the study is to investigate the existing flexible pavement conditions by means of laboratory testing consisting of physical, volumetric, and performance tests using collected core samples. As a result, the data collected was compared to the Malaysian Public Work Department’s (PWD) standard. Data from laboratory tests was analyzed using Response Surface Methodology (RSM) to determine correlations with parameters influencing distress. Historical data design was carried out between test components and responses, which consisted of laboratory parameters. Axial strain, tensile strength ratio, and stability were the responses measured in the RSM. The created models between the independent variables and responses revealed a high level of correlation. The binder content, degree of compaction, and stiffness were the most significant operating parameters from the 3D plots. Optimized performance due to asphaltic pavement failure was observed at binder content (5.1%), degree of compaction (97%), and stiffness (3.1 kN/mm) to achieve ultimate axial strain (5000 microstrains), tensile strength ratio (80%), and stability (9.2 kN). The study showed that the response surface methodology (RSM) is an effective statistical method for providing an appropriate empirical model for relating parameters and predicting the best performance of an asphaltic mixture to reduce flexible pavement failure

Microstructure analysis of porous asphalt incorporating kenaf fiber in the pavement

Hot mix asphalt (HMA) is the most of the popular pavement in Malaysia and most economical materials available. Besides that, this pavement type also very suitable with this country climate but HMA need frequency rehabilitation and maintenance due the damages caused by traffic load. In ways to minimize the damage and increase the services life of pavement, modification of asphalt binder is one of the approaches to improve pavement performance and services life. HMA can be modified with many types of fibre including natural fibre. This study utilises the usage of natural fibre as modifier of porous asphalt. The performance of modified porous asphalt is assessed by microstructure analysis. Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), Fourier Transform Infrared Spectrophotometer (FTIR), Powder X-ray Diffractometer (XRD), and Permanence Deformation Resistance are some of the laboratory results that have been used. The characteristics of PA modification with 0.3% kenaf fibre are demonstrated in this research. In the interior structure of PA, kenaf fiber diffuses effectively. C and Ca elements contributed the most in the experiment, as did the element and chemical content of PA modified with kenaf fiber. In comparison to the control specimen, changed PA has more persistent deformation and PA with 0.6% kenaf fiber had the greatest resilient modulus value. From the results, it displays that the addition of natural fibre is able to enhance the performance of porous asphalt. This study also promotes the sustainable building materials especially in pavement construction

Assessing surface defects of flexible pavement at parking lot due to undesirable commercial activities

Flexible pavement can be considered as the main mode of transportation nowadays as it is most reliable and have more users per day. As the pavement technologies developed over time, they manage to build pavement which is durable and economic. Even so, surface distresses can occur if the pavement was constructed poorly and also does not have regular maintenance. The purpose of this study is to investigate the relationship between the surface deformation at the parking lot with the undesired utilities of commercial vehicles by using visual observation and also image analysis software. From this study, four different locations which are two from inside institutional parking lot area and other two locations from outside institutional area. The two location that we choose must be a location with business activities and location without business activities as a comparison of the severity of the pavement. Pavement severity distresses analysis usually done on a highway as it has more traffic load and also the vehicles have higher speed. From the results, it clearly shown the existence of all four types of surface defects. It is also usually done using manual method which are using special ruler and visual observation. Thus, it is dangerous as the data must be read on site and also it needed more workers for the observation. For our approach, we take the data on site and use visual analysis software to get the data which is much safer

Prediction of HMA mixture performance from rheological and rutting evaluation of nanopolymer asphalt binder

Recently, the interest among researchers in nanopolymers used in modified binders has increased in order to achieve high performance of the bituminous mixture. This work presents a study on HMA with different nanopolymer proportions and different mix gradation types conducted to evaluate the rheological performance of asphalt binder and HMA mixtures. The design method of the Marshall mix was used to achieve an optimal asphalt binder content with a different proportion of nanopolymer polymer modificers. The resilient modulus test was conducted to measure the stiffness of the HMA mixtures, while the dynamic shear rheometer test with a short-term aging technique was used to evaluate the rutting of the asphalt binder. The regression analysis was used to test the performance of the nanopolymer rheological asphalt binder and HMA asphalt mixture. Empirical and predicted data from experimental research have been used to construct and validate regression models. The rheological asphalt binder has been shown to have a significant effect on the performance of the HMA asphalt mixture. This result has shown that the finding provides guidance for predicting the performance of HMA asphalt mixtures with respect to the performance of the rutting asphalt binder and, as a result, nanopolymer can be used as an asphalt modifier in road construction

Performance characterization of stone mastic asphalt using steel fiber

SMA is a gap-graded hot mixture designed to provide higher resistance towards permanent deformation and rutting potential by 30% to 40% more than dense-graded asphalt, due to its stable aggregate skeleton structure. However, compared to other types of hot mix asphalt, SMA unfortunately has some shortcomings in term of its susceptibility towards moisture-induced damage due to its structure and excessive bitumen content in the composition. This research aims to assess the performance of a SMA mixture with steel fiber by enhancing overall stability, abrasion resistance, and, most importantly, moisture susceptibility. This study involved the incorporation of various steel fibre proportions of 0%, 0.3%, 0.5% and 0.7% by the total weight of mixture. The steel fibre modified SMA was made up of 6.0% PEN 60/70 bitumen content. The performance of SMA were evaluated through Marshall stability and flow test, Cantabro loss test and indirect tensile strength test. The results obtained from the testing showed that the incorporation of steel fibre is significantly effective to enhance the resistance towards moisture damage, while increasing the stability and reducing the abrasion loss of SMA mixture, compared to conventional mixture. Overall, it can be concluded that the addition of steel fibre in asphalt mixture specifically SMA, has improved the mechanical performance in the application of asphalt pavement with the optimum steel fibre proportion of 0.3% by the weight of mixture. The developed models between the independent variables and responses demonstrated high levels of correlation. The study found that response surface methodology (RSM) is an effective statistical method for providing an appropriate empirical model for relating parameters and predicting the optimum performance of an asphaltic mixture to reduce flexible pavement failure