In Thailand there are more than 100,000 traffic accidents and traffic-related casualties of approximately 12,000 deaths per year. Even though there is no specific statistic in Thailand, it is believed that rear-end collision is the most common type of road accidents. The aim of this research is to mitigate or reduce the severity and the number of road accidents, especially rear-end collisions. This research implemented the “dot” tailgating treatment pavement markings to assist drivers in establishing the recommended following distance. The recommended following distance is derived from asymptotic stability condition of the GM 5th car-following model and calibrated with data collected on the national highway 1141, Thailand. The relationship between flow rates and distance headways were investigated before and after implementing the “dot” treatment pavement markings. Distance headways are then used as a measure to examine the effectiveness of the markings. It is found that for a given flow rate distance headways increase after implementing the markings or the likelihood of rear-end collisions is reduced at the study site.
Mixed traffic flow with high composition of motorcycles is a common situation in most Asian countries such as Taiwan, Thailand, Vietnam and Malaysia. To date, there are approximately 7.5 million of registered motorcycles in Malaysia and motorcycle ownership in Malaysia has increased from 0.13 in year 1990 to 0.28 motorcycles per person in year 2006. Observation in the field indicates that motorcycles can traverse through signalised intersections in certain distinctive ways as compared to other motorised vehicles. In this study, motorcyclists’ travelling through an intersection was divided into those within the flow and those outside the flow. Motorcycles within the flow follow a first-in-first-out rule, implying that they travel either in front of or behind other vehicles in the traffic stream. Motorcycles outside the flow are those that do not follow the first-in-first-out rule. This study attempts to investigate the effect of these motorcycles travel behaviour on saturation flow rates at signalized intersections. The results showed that motorcycles inside flow should be considered in the estimation of saturation flow rates.
This research involves development of total, damage, injury and fatal accident models in Malaysia along a two lane single carriageway road, a typical Federal trunk road adjoining big towns in Malaysia. HDM-4 the road safety evaluation is carried out using look-up tables of accident rates with user defined accident costs. The Poisson and negative binomial modelling technique were used to model the accident prediction. With this model development the road accident costing will be based on a fluctuating accident prediction. Road user costs comprises vehicle operating costs, costs of travel time and costs to the economy of road accident costs, i.e. loss of life, injury to road users and damage to vehicles and other roadside objects. The accident costs and subsequently the road user costs will not be based on a static accident prediction but instead will be based on accident prediction based on the traffic and road environment in different road categories. These fatal, injury and damage only accident prediction models will be used in the road user effects (RUE) model in HDM-4. This paper looks into the research methodology and the data collection aspects of this research.
Roads are a vital component of the economic and social development of modern nations. The provision of all-weather roads from farms to markets acts as a catalyst to economic growth. Larger and larger areas of nations are opened up to viable mining and agriculture and new cities evolve to service the needs of the regional communities. Within metropolises, road transport permits greater efficiencies in manufacturing, for example facilitating just in time production and distribution systems. Roads are also a critical element of poverty alleviation programs. Breaking the poverty cycle requires access to schools, to jobs and to a range of community facilities, such as health services. In short, the development of road infrastructure and the evolution of modern road transport systems is essential to mankind's development. (a) For the covering entry of this conference, please see ITRD abstract no. E214938.
Determination of merging capacity for a freeway ramp section is important when one analyzes quality of traffic flow at freeway system. It is believed that merging capacity of a freeway ramp merging area can be calculated mostly by analyzing headway distributions of a freeway basic section upstream of freeway ramps. However, because of the fact that headway distribution of the freeway basic section is to change prior to arriving at the ramp segment, the existing method results in an overestimation. In this research, an attempt was made to redefine the headway distribution at a freeway ramp merging area and the refinement accounted for a set of various effects of vehicles merging behaviors on freeway merging capacity calculations. The most distinctive characteristic of the suggested headway distribution is to reflect ramp traffic volumes as one of the parameters for calculating the merging capacity. Gap acceptance model was developed in this procedure for checking the possibility for an entering vehicle within the ramp to merge into freeway main flow. Also mathematical analyses were made to determine the merging capacity for the total traffic flow. It was found that the possible merging capacity must be decided by combining freeway main line flow and ramp flow. Some of merging capacity calculation results produced in this research showed much different values from the ones in the Highway Capacity Manual. This suggests that by using the proposed method more efficient ramp designs and freeway flow managements can be realized. (a) For the covering entry of this conference, please see ITRD abstract no. E214938.
