The interfacial pressure between tire and pavement is known to exhibit a highly non-uniform distribution over its contact area. This differs significantly from the uniform contact pressure distribution used traditionally in pavement design and analysis. Past research efforts have recognized that the contact stress distributions are dependent on tire type, tire inflation pressure, wheel load, tire tread patterns and vehicle rolling characteristics. This paper discusses the development of a numerical model that is capable of describing the contact stress distributions at the interface between a rolling tire and the pavement. The theoretical development of the finite-element based simulation model is first described. This model is then validated against the experiment data available in the literature and is applied to simulate the stress distributions at the tire-pavement contact area under different rolling conditions

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Due to the variations of the material properties and construction in pavement engineering, pavement responses under vehicle loading are stochastic. The use of stochastic approach in the pavement analysis is more reasonable. The purpose of this study is to develop a perturbation stochastic finite element program in the pavement analysis and the results are compared with the results of a Monte Carlo simulation approach. Then, the statistical data from the stochastic finite element analysis are incorporated with the reliability method to develop performance function models. The reliability-based performance models will be used for performance analysis of test pavement sections. The First Order Reliability Method (FORM) is used to compute the factor of reliability for rutting and fatigue cracking of pavement. The results of these analyses can be used to study pavement performance reliability.

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Abstract: Solid waste management is one of the major environmental concerns in the world, 1 billion end-of-life tires are generated globally each year .Several studies have been carried out to reuse scrap-tires in concrete. This paper reviews many of the works used particles of scrap tires or waste rubbers as fibers or chips in rigid pavements as rubberized concrete. Particles of scrap tires can effectively improve the toughness, shrinkage, and durability characteristics of concrete pavements. The use of waste rubbers from industrial or postconsumer waste offers additional advantages in waste reduction and conservation.

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Nowadays, material resources used for pavement materials decreased with the increasing volume of road infrastructure. Recycling technology using Foam Bitumen is appropriate to overcome the limitations of pavement materials and to repair all damages in the pavement layer. In addition, the use of CMRFB-base is environmental friendly, because it can reduce the use of fresh aggregate. This research was conducted to determine the laboratory performance of Recycling Mixed Cold Asphalt Base with Foam Bitumen (CMRFB-base) using cement filler. If the percentage of cement is too high, the mixture will have a tendency to become more brittle so it can reduce the resistance to loading. By using 100% RAP of CMRFB-base with 1% PC, their laboratory performance is better then that of using 1.5% PC. It is recommended to conduct a future research for CMRFB-base and to compare the laboratory performance of the mix with its performance in the field.

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Traditional practices of pavement crack maintenance prioritization are often based on subjective assessments and only consider crack width as the defining measure for representing severity of the cracks. In reality crack severity should logically be a function of the remaining fatigue life of a pavement. This assessment requires all characteristics of a crack to be considered including the depth and location of a crack for considering a mechanistic analysis as the basis for crack maintenance prioritization. This paper aims to improve the operational capability and practicality of the proposed approach by developing a crack prioritization model to establish maintenance priorities. The model is calibrated and validated, which is considered critical for any model, using a cross validation approach. The results from the validation process support the feasibility, practicality and wide-scale implementation of the proposed mechanistic approach.

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In Malaysia, most of the pavement is made with hot mix asphalt (HMA) as this is one of the most economical materials available and it is also very suitable for the climate here. However, the HMA pavement normally required frequent maintenance and rehabilitation due to damages caused by excessive traffic loadings. Therefore, one of the alternatives to minimize the damages of pavement and to prolong the service life is to use modified asphalt pavement. HMA can be modified with filler, extender, rubber, plastic, rubber-plastic combinations, fibre, antioxidants, hydrocarbon, anti-stripping agents, waste materials and etc. This study demonstrates the properties of HMA added with coir fibre and kenaf fibre. The laboratory result reveals that both fibres are effective in increasing the Marshall stability of ordinary HMA. The coir fibre and kenaf fibre increases the Marshall stability of ordinary HMA by 3.2% and 9.7% respectively.

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The increase of traffic volumes on the roads consequently increases the tyre pressures and produces heavier axle loads imposed on pavement structure. Hence, there is a need to enhance asphalt pavement mixtures that may prone to rutting, to withstand the increase traffic loading, mitigate adverse effects on pavement performance and reduce thermal pavement cracking. Therefore, it is important to study material such as reclaimed rubber that has a potential to be admixture in hot mix asphalt. In this study, old car tyre tubes were used as an admixture in hot mix asphalt. The reclaimed rubber were cut into various sizes to determined the effect of different size used. This study shows that size of rubber can affect the performance of reclaimed rubber modified asphalt mixes (RRMAM). Small size reclaimed rubber can provide more stability than bigger size of reclaimed rubber.

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After decades of experience in road construction, the highway experts have concluded that the major failures on road network of Pakistan are rutting and fatigue cracking. These failures are primarily due to the high temperatures and the prevalent overloading. To minimize these defects, highway engineers have to adopt new technologies instead of resorting to conventional dense graded asphalt mixtures. One of the technologies to address these problems is Stone Mastic Asphalt (SMA). SMA is a gap graded mixture, which provides durable pavements, exhibits high resistance to rutting caused by heavy truck traffic and proved to be extremely effective in combating early deterioration of the pavement. A test section was laid on a in-service segment of National Highway through a joint collaboration with National Highway Authority to evaluate the performance of cellulose based SMA on our road network on the basis of certain field and laboratory tests

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This paper investigates urban expressway capacity characteristics of lane closure sections due to accident. The methodology includes the following parts: 1) identification of a breakdown due to an accident, 2) estimation of capacity under accident conditions, 3) exploring features of capacity drop percentage, and 4) fitting probability distribution of capacity drop percentage. The results reveal that mean capacity value increases and its variance turns to be convergent with increase of lane closure duration. It is found that a higher possibility of greater capacity drop percentage exists under accident conditions. More severe accident types such as multiple rear-end collisions and rear-end collisions result in comparatively greater values of capacity drop percentage. Furthermore, capacity drop percentage is shown to be stochastic, and beta distribution can well fit its probability distribution.

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The road length has been increased every year in Korea. However the human resources have not increased or even the human resources have been decreased. For the high maintenance office face with difficulty to manage the road highway with in-house method efficiently. Therefore the contract or outsourcing to the private sector for road management and maintenance is highly required in Korea. When contracting or outsourcing, it is necessary to decide the proper management coverage or road length and the location for each private maintenance office. Therefore in this study we calculated the current office routine maintenance coverage with the current office human resources. We figure out the needed number of private outsourcing maintenance office and optimized the private maintenance office location with the genetic algorithm and GIS. While this process we calculated the current road maintenance workload and needed number of teams with the GIS analysis.

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A scientific methodology specified by Normalized Development Level (NDL) for international comparison of the accessibility in expressway network is developed with consideration of the difference of countries in their area, population, economic development level, geographical conditions including seismic risk, which is applied to time series data of various countries over the world including EASTS' member states. Furthermore, an index to measure the regional balance of expressway development: Regional Balance Index (RBI) is also proposed based on the calculated results of NDL and applied to the time series data in Japan, US and EU. This comparison approach based on a simplified theory which can be widely applicable even for countries and regions with limited data-availability seems practically useful for evaluating of current situations in different countries, different regions, and different times comparatively, for reviewing history of development, and for discussing direction of long-term development policy of expressway network for the future.

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Repeated wheel load and temperature thermal stress will cause stress and strain and then deteriorate pavement's performance. It is important to identify damage to stop it only at the surface layer and not to spread to the lower layer by measuring tensile stress and strain under stress applied. The research aim is to know Hot Mix Asphaltic Concrete behavior on surface pavement, which includes tensile stress and strain, and its resilient modulus under load and temperature changes with laboratory test using UMATTA. Load varies from 187,5 to 2000 N, while temperature varies between 25, 37,5 and 50 0C under 1 and 0,3 Hz frequency. The results indicated that temperature is the most responsible for pavement surface damage compared to load and load frequency.

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Alkali-silica reaction (ASR) is a major durability problem that results in a very severe deterioration in the portland cement concrete pavement. The deterioration based on ASR in the cement concrete occurs when alkalis from the cement or from an external source react with free silica from certain aggregates to form an alkali-silica gel. A variety of effort has been provided to establish the method to prevent the ASR problem in the new construction and rehabilitate the existing deteriorated pavement sections due to ASR in Korea. It is expected that the placement of BCO can prevent the additional water intrusion into the existing pavement with the aggregate easy to accelerate ASR and stop the additional ASR related distress. The purpose of this study is to establish method for the rehabilitation of the deteriorated pavement caused by ASR of concrete pavement by the BCO with Very Early Setting Latex Modified Cement.

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The surface deflection measurement is the widely used nondestructive test to investigate the structural strength of flexible pavement. Traditionally the test is conducted using the Benkelman Beam which is equipped in all district offices of thailand's Department of Rural Roads. At present, the modern Falling Weight Deflectometer (FWD) becomes more popular to measure the deflection due to the improvement in fast processing time and amount of data obtained. The important thing of using the FWD data is to have a sound interpreting technique that is capable of evaluating the pavement structural condition correctly. This work presented the potential of using the deflection to evaluate the structural strength of newly constructed asphalt pavement. Based on the field testing data, it was found that the deflection at load center (D0) and the total thickness of pavement correlated well with the modified structural number, or SNC which represented the structural capacity of pavement for carrying traffic loading.

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In this paper, the implementation of using waste cooking oil as a rejuvenating agent that used in RAP is investigated. The simulation of ageing process is accelerated by unconventional method using propeller mixer and rolling thin film oven test (RTFOT). The binder tests that undergone in this research are Penetration Test, Softening Point Test which is well known as Ring and Ball Test, Brookfield Viscosity Test and Dynamic Shear Rheometer, (DSR) Test is conducted to measure ageing properties. It was observed that unconventional method produced aged bitumen group of 60/70, 50/60, 40/50 and 30/40 which have penetrations between of 60 to 70, 50 to 60, 40 to 50 and 30 to 40, respectively while RTFOT shown 50/60 aged penetration grade. The results indicate that the aged bitumen is rejuvenated by the waste cooking oil due to change in physical and rheological properties that revived to original bitumen (Fresh Bitumen).

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This study aims to develop a performance grading system using indirectly estimated parameters related to pavement performance and conditions in Thailand. After the validation of such developed system, it has been found that the proposed performance grading system can be satisfactorily used to classify the binders by its performance which is also comparable with the SUPERPAVE system. It should be, however, noted that the proposed system can be used as a transition before obtaining the sufficient equipment and gaining sufficient understanding for SUPERPAVE implementation.

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Back calculation of pavement modulus values from surface deflection bowl data is still the best known technique for the evaluation of the structural condition of an existing pavement. Conventionally, matching the theoretical with the measured deflection bowls is performed using convergent approaches. Yet, apart from producing many solutions, back calculation may also take a reasonable long computation time. Back calculation is essentially an optimization process that could be solved using genetic algorithms, as outlined in this paper. As the results, better matching between the theoretical and the measured deflection bowls was obtained and the resulting back calculated pavement modulus values were found to be quite consistent resulting subsequently in quite similar overlay thicknesses.

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Bitumen penetration grade 80/100 was modified with oil palm fruit ash (OPFA) to improve its resistance to the change of pavement temperature and its physical properties. OPFA is a waste by product of palm oil mill, the ash of burning mesocarp of palm oil fruitlets. OPFA with uniform grain size less than 0.075 mm was added to the bitumen 2.5, 5, 7.5, and 10% by weight of the bitumen. The mixtures of OPFA and bitumen or OPFA-modified bitumen (OPFA-MB) as well as the base bitumen then were aged using rolling thin film oven (RTFO) and pressure aging vessel (PAV) prior to rheological testing using dynamic shear rheometer (DSR), bending beam rheometer (BBR), and direct tension tester (DTT). The results show that OPFA-MB content 5% OPFA can resist permanent deformation or rutting at high temperature 70 degree Centigrade, fatigue cracking at intermediate temperature 20 degree Centigrade, and thermal cracking at low temperature -15 degree Centigrade.

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The goal of this research is to establish spacing requirements for access points to managed lanes (MLs) with respect to the location of entrance and exit ramps on the general purpose lanes (GPLs) of the freeway. Traffic entering the freeway destined for the ML must weave across the GPLs. Traffic exiting the freeway from the ML must also perform this maneuver. The process of developing guidelines can be achieved by the sensitivity analysis of capacity with respect to the ML access spacing. Microscopic simulation is used to develop guidelines. The key factor in determining the required ML access spacing is the ramp to ML flow (or the ML to ramp flow in the exit ramp case). In the simulations, the capacity increases as the weaving distance increases to a point where the maximum capacity is found. Minimum required weaving lengths are selected where the increase in capacity levels off.

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This paper investigates a parking reservation mechanism to help reduce car cruising for parking, which not only makes drivers uncomfortable, but also harms the environment by air and noise pollution. To consider the benefits for drivers and parking facility providers, we suggest charging drivers for making reservations in addition to parking fees. A reservation pricing model that makes reservation prices equivalent to the value of saved searching time is developed. By modeling the number of vacant spaces as a stochastic variable and applying binomial pricing method, the parking reservation prices are obtained. Numerical examples based on the data for two different sized parking facilities in Taiwan are followed. The simulation results show that the proposed parking reservation system decreases the searching costs for these two parking facilities by 27% and 42%, increase the revenues by 13% and 25%, and reduce average emissions by 432 kg and 1,245 kg per week.

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The purpose of this paper is to grasp effect of flood puddle to durability of asphalt concrete mixture on road pavement. In this regard, an experimental study was carried out by using Modified Immersion test in order to represent the flood phenomenon and Marshall Immersion test as reference. The experimental treated immersion test during 1, 3, 5, and 7 days to the two types of asphalt mixture, i.e. the mixture containing Retona additive and un-containing it. The research adopted three types of durability indexes, i.e. the retaining strength index (RSI), the first durability index (FDI), and the second durability index (SDI). The results show that Modified Immersion test gave good appearance to grasp deterioration of the mixtures durability due to flood puddle during some days. In further, the asphalt concrete mixtures still retained until seven days immersion, where the mixture containing Retona was more durable than the other mixture

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Although the inertial profiler has been introduced for decades, most of the highway agencies in Taiwan still adopt the 3-M straightedge as the main device for pavement roughness measurements. Through the Long Term Pavement Performance database, 5280 profile data were selected in this study for analyzing the relationship between international roughness index (IRI) and standard deviator (sigma). The natural logarithm transformation was applied to both variables before a linear regression model was developed with R2 of 0.9368. However, it is found that the current smoothness acceptance specification (sigma= 2.4 mm) used by Taiwan Freeway and Expressway system is equivalent to an IRI value of 2.97 m/km that is not rigorous enough while compared with that of other countries. It is recommended to modify the sigma specification from 2.4mm to 1.1mm that will perform an equivalent level of the IRI-based specification suggested by Federal Highway Administration.

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A road generally has a variety of characteristics and there are several elements which diversly affect the traffic safety and pleasantness and service expenses, etc. in time of operation. Among several elements, the evenness indicating the condition of a road surface not only operates as a determinant controlling a rough or smooth ride but it also gives a considerable effect on safety concerns.

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A two-lane road, as a road having very great weight, occupies 51.4% of the general national roads and 72.6% of the local roads[state-supported local roads included] and it is operated in the way of letting only one-lane available by direction. When a traffic jam arises due to a front-running vehicle, there is a characteristic of having to overtake it by using the lane for the opposite direction. However, most of our topography is mountainous and what is worse, the length of overtaking section is limited to 200m ~400m. Thus, there exist a lot of limits to high-speed vehicles' overtaking. Particularly, traffic delays are ever aggravating due to the traffic characteristic of the high mixing rate of truck traffic.

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Asphalt concrete wearing course is provided on highways throughout the world to provide a smooth and watertight surface for comfortable ride. Majority of highways including motorways in Pakistan are facing acute rutting problem. Research has been conducted by various agencies to investigate causes of such failures. A number of techniques have been used to reduce these distresses, but these techniques either do not work or they are uneconomical. Pakistan, National Highway Authority (NHA) is gradually shifting towards reinforced concrete lanes for heavy traffic, which are far more expensive than asphalt concrete roads. A new technique of using tempered glass is being proposed as replacement of asphalt concrete wearing course in highways. The innovative technique may provide a solution to the chronic problem of highway distresses.

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The green growth is one of critical issues to mitigate greenhouse gas emissions and reduce fossil fuel to promote sustainable economic development in the world. In order to build environmentally sustainable asphalt pavements, a wax-based WMA additive, called low energy and low carbon-dioxide asphalt pavement (LEADCAP), was developed to reduce mixing and paving temperatures applied in asphalt paving process in Korea. The main objectives of this study are to build WMA field trial sections using LEADCAP additive along with the control HMA section and to measure the emissions and fuel consumption in the plant. Also, rutting resistance of WMA mixture using LEADCAP additive is evaluated in the laboratory. Based on the limited laboratory and field experiences, the energy savings and the air quality improvements by WMA mixture were observed and rutting resistance of WMA mixture is superior to that of HMA mixture.

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This study investigates expressway breakdown phenomenon considering flow characteristics on individual lanes. Methodology includes the following parts: 1) identification of trigger of breakdown on individual lanes, 2) exploration of interactions between lanes, 3) analysis of breakdown and discharge flow rate of individual lanes and 4) modeling breakdown probability distribution considering lane utilization ratio. It is found that breakdown is usually triggered firstly on median lane. A strong interaction of median lane upon shoulder lane could be ascertained quickly after trigger of breakdown in median lane. In addition, median lane suffers much greater capacity drop when breakdown occurs compared with shoulder lane. Furthermore, breakdown probability is modeled using Weibull probability function by considering impacts of traffic demand,heavy vehicle percentage and lane utilization ratio. A lane based method is proposed to model breakdown probability.

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The concrete pavement thickness design process requires the input of whether the pavement has doweled joints and/or concrete shoulders. This paper presented the practical design thresholds in terms of cumulative truck traffic to help the engineer to judge the important of doweled joints and/or concrete shoulders in thickness reduction. The Portland Cement Association Method was applied for the thickness design. The results showed that the concrete shoulders could contribute to the thickness reduction in the light truck traffic condition. The doweled joints could contribute to the thickness reduction in the heavy truck traffic condition. The thresholds were 12 million and 15 million vehicles of cumulative truck traffic, for the traffic category 3 and 4 respectively. The doweled joints could not reduce the pavement thickness for the traffic category 1 and 2 when the cumulative truck traffic is less than 2 million vehicles, but the concrete shoulders could.

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In order for bicycle riding to be settled the use of a bicycle for leisure and life should be pursued at the same time while the bikeways for living in Korea still remain poor. This Study examined the current status of bicycle use and problems with regards to construction at national highways and presents adaptable design methods and types. For the purpose, this Study conducted on-the-spot surveys of about 90 sections (882.2km), which are judged to be necessary to construct the bikeways at living zones on national highways across the nation, and the design methods were identified based on the survey results. So it is anticipated that the bikeways at local living zones will be expanded and their use is activated

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Reflection crack is one of main problems on road pavement in Indonesia. Reflection crack is a crack will reflect through an overlay placed on top of it. One of methods used in improvement of reflection crack resistance is Stress Absorbed Interlayer (SAMI). The purpose of this study is to evaluate the SAMI layer with different conditions. The types of bitumen used in the SAMI were 60/70 penetration grade bitumen and polymer modified bitumen with using various SBS contents. The SAMI layer systems used in this research were one layer and two layer systems. The samples of 30 cm x 30cm x 5 cm size were prepared using Whell Tracking Compacter. The SAMI had a significant effect on fatigue crack performance, which bituminous mix using SAMI exhibited better in reducing reflection crack compared to conventional bituminous mix. The use of the SAMI with one layer system and modified bitumen with 2% SBS showed the best performance in term of the fatigue crack.

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One of efforts for sustainability in Road Pavement Materials agenda is reducing virgin material in road pavement construction and increasing the use of waste materials as alternative materials in road pavement materials without reducing quality of pavement structure. The objective of this paper is to discuss the use of product waste materials from industry for road pavement construction in Indonesia. Waste materials used in this study as additive materials on road construction are Residium Catalytic Cracking 15 (RCC-15), lignin, slag and tailing. Generally, test laboratory results showed that road construction containing waste materials have higher performance than conventional road construction

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As global warming causes environmental problems around the world, international discussions such as the Cancun Conference (2010) etc. are actively discussing issues concerning such issues. Korea actively participates in confronting international climate change. Korea is seeking specific ways of applying green technology development so as to contribute to the reduction of carbon emissions and energy consumption. There is a need for the development of proprietary technology appropriate to the national condition and this fact further emphasizes and confirms the need to develop "Carbon Neutral Road Technologies". In order to develop roads which have this carbon neutral state, there is a need to minimize the emission of CO2 and environmental burden in the process of developing and maintaining roads. There is also a need to use road facilities and unused areas of the road to construct roads which are capable of energy production and techniques in order to maintain such facilities.

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In this study, a self-tuning signal control algorithm is developed for isolated intersections. Traffic dynamics at signalized intersections are represented on time-space diagrams. Unlike most algorithms, the proposed method uses occupancy information and can manage traffic even when queues extend beyond detector locations. Simulation experiments on a four-phase intersection with different demand scenarios are performed to demonstrate efficiency of the developed algorithm. It is found that in case of fixed demand, the proposed method can optimize splits and cycle lengths with no worse performance measures than the optimal fixed-time signal settings. For the variable demand case, the result indicates that the algorithm can adjust splits and cycle lengths in response to the change of demand and provides better performance measures than the Webster formula.

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This manuscript presents changes in bottleneck capacity at a freeway diverge in Bangkok. This bottleneck was caused by an exit ramp queue moving upstream onto the freeway. Detailed traffic data from an expressway in Bangkok show that traffic states during bottleneck activation could be grouped into three states with different levels of capacity based on vehicle speeds on through-movement lanes and the rates of lane changing maneuvers near the off-ramp queue. Data also indicate that the transitions of traffic states were primarily caused by the changes in exit flows. The lower capacity was initiated by a more restrictive off-ramp flow that causes cut-through vehicles on the adjacent lane impeding through-movement traffic. Once relaxing the exit flow, impeding vehicles could move out of the adjacent through lane and higher capacity often restored. These findings also show how automatic off-ramp control strategies could generate higher bottleneck capacities through detecting traffic speeds on the freeway.

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This study was conducted to measure the improvement of the traffic flow after the implementation of the Integrated Transport Information System (ITIS) in Kuala Lumpur City. The ITIS is an intelligent transport systems (ITS) comprise of two core support systems, namely the Advanced Traffic Management System (ATMS) and the Advanced Traveller Information System (ATIS). In this study, simple linear regression method is use to analyze the effectiveness of the ITIS in Kuala Lumpur city centre. From the simple linear regression method, it shows that the basic parameter of traffic flow (speed and density) at the study location has strong relationship to each other. Using the generated simple linear regression equation, the average travel speed during peak period was predicted. Overall, the ITIS were found to be effective, with the average travel speed increases when density increases.

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This study aims to investigate the drivers perceived effectiveness to the implementation of the traffic information system in Klang Valley region, Malaysia. Five evaluation indicators are chosen, namely usefulness, accuracy, reliability, satisfaction, and benefits of travel time saving. Using the revealed preference study, drivers are asked to evaluate the system effectiveness based on these indicators as well as the awareness and utilization of the system. Ordered probit models are developed to analyse the significant contributing factors to the perceived effectiveness. Results indicate that drivers perceived radio as the most effective tool. Drivers show play safe mindset in which they adjust their trip despite having full confidednt on the information. It is found that about 56% of the drivers perceived the system as useful while further improvement is much appreciated.

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This paper aims to evaluate the effects of work zone configuration, traffic flow and heavy vehicle percentage on traffic delay at work zones by using a heterogeneous cellular automata (CA) model. The activity area length and transition area length are two work zone configuration factors taken into account. The average traffic delay per work zone and the average traffic delay per 100m are the two indices used to express traffic delay at work zones. The graphical comparison results show that the transition area length has much bigger effects than the activity area length on traffic delay, especially in the light traffic condition. The function of average traffic delay per work zone is finally formulated that can be used to estimate the marginal effects of the activity area length, transition area length, traffic flow and heavy vehicle percentage.

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In the last five years the motorcycle use in Indonesia was growing rapidly. In Indonesian Highway Capacity Manual, IHCM (1997) percentage of motorcycle was significantly lower than recent condition. This is due to severe congestion as an impact of unsatisfactory public transport services and uncontrolled city development. Whilst improving the quality of public transport, city transport authority needs to manage motorcycle traffic, e.g. by implementing motorcycle lane. In this paper only motocycle lanes in Jakarta and Sragen will be evaluated in terms of rate of effectiveness and rate of exclusiveness. Person correlations between these rates and V/C were evaluated. There was no clear pattern of sign of Pearson correlation (r) between rate of effectiveness and V/C (volume to capacity ratio) and between rate of exclusiveness and V/C. Therefore effectiveness and exclusiveness of motorcycle lane were not related to V/C but rely more to the motorcycle lane system and design. Furthermore, law enforcement is a must if the system and design of the motorcycle lane are easaly violated.

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Vehicular time headway is of fundamental importance in traffic engineering. This research investigated theoretical headway models for a multilane highway in Korea using loop detector data. To analyze time headway by traffic flow states, the collected data were categorized into five flow rates and tested for randomness. Subsequent theoretical modeling was performed at the five flow rates. The Gamma distribution at low to intermediate flow rates, and the Pearson VI distribution at all flow rates were fitted by the K-S statistic. Model parameters were obtained from conventional maximum likelihood estimation. Analyses were performed on residuals and parameters of the fitted models, as well as various headway statistics. Notably, parameters of the Pearson VI changed markedly during level of service C, which presumably reflects the boundary between low and high traffic flows.

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The aim of this study is to analyze the patterns of AVI (Automatic Vehicle Identification) misreading errors. 2009 ITS performance evaluation results show that the performance level of equipments becomes low as they grow old. Also AVI is more suitable for day time collection than night time. From the analysis of errors, there are two types of errors; similar shape error and errors due to different number plate types. In the result and analysis part, we talk about these types with figures. In conclusion, to assure the ITS reliability, it is necessary to maintain the equipments regularly.

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Traditional probe vehicle data collection system uses OBU (On Board Units) to receive positioning data. It requires complicated data filtering, map matching and calculation in the back-end system. When the number of probe vehicles increases, sending, collecting and analyzing the huge data becomes costly, complicated and time-consuming. To resolve this problem, a Virtual Vehicle Detector (VVD) system with a method to set up VVD on road network is proposed. The idea of VVD system was that if road users had OBU, traffic control centers would be able to send a preplanned VVD data structure to the OBU and efficiently collect data by the triggering software. Results of a field test on the Taiwan highway No. 1 show that the proposed VVD mechanism is able to help accurately trigger positioning records. This could simplify the process of back-end data analysis, and reach the goal of efficiently collecting travel time and traffic volume.

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This study presents essential information on motorcycle rider characteristic and behavior resulting from the questionnaire survey for riders and non riders that was conducted along the top 5 roads in Metro Manila with the most number of recorded motorcycle road crashes in the past 5 years. The questionnaire has eight sections that focus on rider personal details, driving experience and training, riding habit, opinion on road safety, road crash experience, motorcycle preference and anger and aggression test. The results of the rider and non-rider survey were analyzed to yield significant variables influencing motorcycle road crash experience and frequency. A total of 2000 motorcycle rider participated in the survey and a total of 600 other road users.

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Space-mean speed is an important parameter in the capacity analysis of rural and suburban highway. The ability to estimate space-mean speed from time-mean speed or spot speed will assist the study to analyse more data, besides saving time and cost. This paper presents the linear regression models developed for estimating space-mean speed for rural and suburban highways in Malaysia. However, due to the different characteristics and driving behavior between two-lane highways and multilane highways, using only one general equation to estimate space-mean speed for both two-lane and multilane highways is unrealistic and inaccurate. Therefore, it is essential to derive separate relationships for two-lane highways and multilane highways in Malaysia. Hence, in this study, specific models for each road facility which are the two-lane highways and multilane highways were derived. Statistical analyses were also conducted and discussed in this paper.

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The KBES developed is a menu driven type using open source programs with three very important web development tools:The Apache for web server, MySQL for database management, and PHP (Hypertext Preprocessor) for scripting C program language. The system guides the user in selecting exact location of congestion or road crash prone areas through an interface. The user deals with series of questions in identifying the cause of the problem which leads to potential traffic control alternative solutions. The KBES was tested at two local isolated intersections in Quezon City,Philippines for validation. The KBES recommendation for the signalized intersection is to increase right turning radius of the corner pavement for trucks to avoid conflicts and delay with other vehicles. For the unsignalized intersection,the KBES recommended a left turn prohibition at major approach to avoid delay and collisions at the approach.

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This paper develops a model to determine and to locate the optimal numbers of license plate recognition (LPR) to minimize error rates of O-D matrix estimation, percentages of LPR coverage (a proxy of installation cost), and percentages of recorded trips (a proxy of privacy invasion). A genetic algorithm is proposed to solve the combinatorial problem. To demonstrate the applicability of the proposed model and solving algorithm, two exemplified cases and a real-world case are investigated. The results have consistently showed that the optimal locations of LPR are at both ends and in the middle of the segments of a freeway corridor with heavy link traffics. If an extensive coverage of LPR is attempted, however, additional LPR may be placed at the segments with light link traffics so as to balance out the privacy invasion.

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This paper develops an adaptive approach for vehicle navigation in a stochastic network with en route traffic information. This stochastic, adaptive approach is formulated as a probabilistic dynamic programming problem and solved through a backward recursive procedure. The formulation is designed to incorporate various sources of information and real time traffic conditions, offering flexibility to incorporate different information types deemed useful in future extensions. In this paper, we prove mathematically that the approach outperforms deterministic formulations in a statistical sense. Results from numerical examples are included to show promise of this adaptive routing policy.

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This paper proposes a concept of critical post-encroachment time (PET) for all-red clearance interval design at signalized intersections that aims at achieving the optimum performance in both safety and mobility. The critical PET is defined as the minimum accepted PET at the conflict point by the first entering drivers. Variability of the accepted PETs in the case of late exit was analyzed at a study intersection in order to estimate the critical PET. Results showed that they follow a two-parameter Weibull distribution and tend to increase as the entering distance rises. Its 15th percentile value, approximately 2.0s, was then used as the critical PET to discuss the implication in the design of all-red time through numerical calculations. Conclusions supported that the calculated all-red time based on the critical PET could achieve significant operational and safety benefits, as compared with the all-red times based on the existing methods.

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In Japan, where vehicles travel on the left side of the road, the queue discharge rates of shared left-turn lane usually show comparable fluctuation, due to different departure characteristics of through and left-turning vehicles as well as interactions with pedestrians and bicycles. For a better evaluation of signalized intersections and then corridor performance, this study investigates stochastic queue discharge rates starting from shared left-turn lane and empirically explores its implications. Results show that efficient utilization of shared lane by through traffic can significantly improve discharge rate. At lower and higher pedestrian-bicycle volumes, discharge rates are relatively reliable. While at middle levels of pedestrian demands, more random arrivals and interactions lead to rather unstable saturation flow rate fluctuation. For the shared lane with a larger left turning radius, its discharge rates display a stable trend.

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The methodology described in Year 2001 Taiwan Area Highway Capacity Manual uses free-flow speed as an input for level-of-service analysis of urban arterials. It does not provide a tool for estimating free-flow speeds. To bridge this gap, this study collects free-flow speeds from fourteen urban arterials in three cities of Taiwan. The data were first used to investigate the characteristics of free-flow speed in relation to vehicle type, geometric design, and speed limit. They were then used to develop models for estimating average free-flow speed and to establish the probability distributions of individual vehicles. Intersection spacing, speed limit, median type, lane location, and vehicle type are found to have obvious effects on average free-flow speed.

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In this paper, we construct a structural model of multiple main factors influencing road section traffic flow and safety, which could not be taken into account using conventional DEA.In this model and road sections are compared in terms of traffic flow and safety and and Network DEA is used to assess comprehensively the maintenance priority on the basis of these two parameters.In addition, the priority assessment of road maintenance sections was tested, taking 64 traffic census section locations f rom Sapporo City's densely inhabited district as a model case.From these results and we found that the maintenance priority becomesclear in cases where multiple factors are considered and and the usefulness of Network DEA is validated through the comparison of analysis results from conventional DEA and the proposed model.

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