The urban population of Metro Manila continues to expand along with high rates of suburbanization at adjoining municipalities. This greater metropolitan region is now referred to as 'Mega Manila'. The resulting urban pattern is one where an increasing number of people live at the fringes of the metropolitan area but still need to travel to the city centers to work or study. In order to sustain economic growth and development and to protect the environment in the region, there is a need to increase mobility through the provision of an integrated public transport system. This paper reviews the various urban development and management issues and policies impinging on the public transport system of Metro Manila. The paper also reviews and evaluates existing policy directions in relation to the development of an integrated public transport system for the metropolis.

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Eight different asphalt binders representing a wide range of applications for flexible pavements were tested in uniaxial tension-, bending- and shear-mode facilities. Theoretical development was made in this study to convert these three engineering properties to stiffness for predicting pavement performance. All three viscoelastic functions were shown to be interchangeable within the linear viscoelastic region. When subjected to large deformation in the direct tension test, asphalt binders behaved non-linear viscoelastic in which the stiffness was not comparable with one obtained from the bending and shear tests. The asphalts were, however, found to exhibit linear viscoelasticity up to the failure point in the steady-state strain region.

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The objective of this study is to provide foundations for selecting pavement structure by sensitivity analysis of pavement structure factors including thickness and modulus of each layer. In this paper, sensitivity analysis is based on orthogonal experiment method. Tensile strain at the bottom of asphalt concrete, compressive strain on top of the subgrade and tensile stress at the bottom of semi-rigid cement stabilized gravel were evaluated using Bisar 3.0 program. Results demonstrate that when conspicuous level ? is equal to 5%, only asphalt concrete thickness h1, graded crushed stone modulus E2 and asphalt concrete modulus E1 have obvious effect on tensile strain at the bottom of asphalt concrete. h1 has the most efficient on all pavement responses. Two types of long-life pavement have been recommended.

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The paper describes recent DFID and World Bank funded research on alternatives to gravel roads in Vietnam and Cambodia. A substantial range of proven, low-cost, rural road paving options is available and many of these have been tested in over 150 road sections constructed in South East Asia. These paving options are suitable for construction and maintenance by Small and Medium Enterprises (SMEs). The paper also reviews the alternative surfacing options. Most of these paving options require little capital investment in equipment, use labour-based techniques and can optimise the use of local materials resources. They can utilize locally made or available simple equipment, thus promoting local manufacturing and appropriate equipment ownership.

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Based on the theory of two-layer elastic system, this paper introduces the formula of equivalent elastic modulus of two-layer elastic system under rigid bearing-plate, and presents the normal figure of equivalent elastic modulus by a numerical method employed in the paper, which can be used expediently in highway engineering. The influences of bearing plate form and other parameters on the equivalent elastic modulus are analyzed; the results show the form and radius of bearing plate as well as Poisson's ratios have a great effect on the equivalent elastic modulus.

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Hydroplaning of vehicles is of concern to pavement engineers as it compromises travel safety in wet-weather. This paper presents a finite-element model to simulate hydroplaning of a locked wheel sliding on a flooded pavement surface. The main components of the model are described and the model is validated against experimentally-derived relationships. The effects of tire inflation pressure, wheel load and water-film thickness on hydroplaning speed are studied using the numerical model. It is found that hydroplaning speed increases with increasing tire pressure, increasing load and decreasing water-film thickness. It is observed that tire inflation pressure is a dominant factor affecting hydroplaning speed while wheel load and water-film thickness are secondary factors. For easy practical applications, a regression relationship of hydroplaning speed as a function of tire inflation pressure, wheel load and water-film thickness is developed using the results of the numerical simulations.

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This paper described a simulative laboratory test to simulate traffic overcompaction using the gyratory compactor. During overcompaction, specimen heights were monitored to determine mix porosity. Mix permeability was measured before and after overcompaction. Resistance to overcompaction was assessed from changes in porosity, height and discharge time. The porosities of all mixes reduced continually until overcompaction ceased. The magnitude of porosity reduction of SLPA mix was highest when overcompacted at higher pressure and on smaller NMAS conventional mix. From the terminal percentage height reduction values, DLPA mixes were subjected to a higher degree of overcompaction compared to the corresponding SLPA mixes. In general, SBS modified mixes were more resistant to overcompaction compared to conventional mixes. The modified mixes also exhibit the lowest percentage change in drainage time.

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This study involved the subjective visibility evaluation of LED roadway delineators under poor visibility conditions. The experiment was conducted using a road in Hokkaido, Japan under natural foggy conditions. The authors employed three types of LED delineators to examine how their visibility differed across various levels of luminous intensity. Twenty women participated as subjects. They were asked to evaluate the visibility, glare, and safety of each test accessory. In heavy fog, LED delineators earned a high rating of subjective visibility at daytime and nighttime. It was also recognized that the luminous intensity of the light-emitting elements in the delineators required adjustment depending on the degree of visibility reduction due to fog: To make the delineator "visible" from the observation distance of 200 m under foggy conditions with a visibility distance of 100 m, luminous intensities of 1,000 cd and 70 cd are desirable for daytime and nighttime, respectively.

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A vehicle traveling on the road exerts a dynamic load on the pavement. A realistic prediction of pavement response can be achieved by using a dynamic finite element analysis. However, the computational model of the finite element method is restricted to a finite domain. It is necessary to use a special boundary technique to consider the radiation condition of the unbounded domain into the finite element model. In this paper, absorbing elements are installed inside the finite element domain to simulate half-space conditions; these can absorb a propagating wave and prevent wave reflection from the bottom boundary. The efficiency of the absorbing elements is verified first, then the elastic structural responses of pavement under three different vehicle speeds are studied. Finally, the developed program is incorporated with the Drucker-Prager plasticity model to predict the permanent deformation of pavement under repeated traffic loading.

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A time domain backcalculation program is developed, and it is used to predict the response of the FWD test from LTPP test sections. The advantage of a time domain analysis is that it can use the time history data directly and is less affected by the error data. The Newmark scheme is used for the time integration, and the pattern search approach of optimization is adopted to perform the backcalculation. First, the backcalculations based on the synthetic data generated by the finite element program show a good agreement between the predicted and given material properties. Then, the backcalculation is performed to analyze the FWD data from the LTPP database; the difference between the predicted and measured data is small. Finally, the backcalculation properties are used to predict the dynamic response of the FWD test in which the deflection data was not used for backcalculation analysis; the results show that the predictions and the test results agree very well.

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This paper describes some laboratory performances of Hot Rolled Sheet (HRS) mixes, according to the New Indonesian Specification, using an Asbuton (Indonesian Rock Asphalt) as fine aggregates and filler. The main laboratory works were : Wheel Tracking test and UMATTA Resilient Modulus test.The results of Wheel Tracking test at temperature 45oC showed that Dynamic Stability were higher for HRS-5 and HRS-10 than that for HRS-0. But the lowest value of Total Deformation obtained for HRS-5. Hence, it can be concluded that HRS-5 give the best resistance to Plastic Deformation at temperature 45oC. The results of Resilient Modulus test showed that resilient Modulus decreases rapidly (30%) as temperature increases from 250C to 35oC and 45oC. But, the deviation occurred for the Resilient Modulus in function of Asbuton content i.e. decrease-increase at 35oC and increase-increase at 45oC. This "abnormality" should be checked and verified by another "future" research.

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Determination of neutral plane position is the key point in the analysis of two layer bonded concrete slab on Winkler foundation, however, there are no solutions for it when the Poisson ratios of two slabs are different. Based on the Kirchhoff hypotheses, the equation of neutral plane was formulated in this paper and numerical method was employed to solve the equation.the position of the neutral plane for the two-layer bonded slab is found out. In addition, the effects of the modulus of foundation, the ratio of Poisson's ratios, elastic moduli and thicknesses of bonded slab on the positions of neutral plane were discussed, and the results show that the position of the neutral plane for bonded slab with different Poisson ratios is totally different from that for bonded slab with the same Poisson ratio.

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This paper describes the cracking behavior of the asphalt pavement surface course when the underlying base course is fully cracked. Finite element pavement model is created using regular finite element. Pavement material properties are obtained from experiments conducted by MTS. Stress intensity factors at the cracking tips are calculated and compared with fracture toughness to describe how cracks propagate from the bottom of the pavement surface to the top. Results show that the cracking growth in asphalt pavement surface course can be divided into stable propagation and unstable propagation.

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Theory of fracture mechanics FM has been employed to determine crack growth rates of the suggested anti-cracking overlay systems. Two different reinforcing methodologies are applied; 1: addition of chopped glass fibers to the HMA; 2: reinforcing asphalt overlay by glass grids. Asphalt mixture designing tests, three points bending tests and fatigue crack propagation tests were carried out. Fracture toughness KIC is determined for plain and reinforced asphalt concretes. The crack growth rate is determined for each type of anti-cracking systems, the cracking process is analyzed. One of the significant points in this study is the attempt to give better understanding of the crack propagation for multilayer asphalt overlay. The results indicate that the reinforcing materials improve anti-cracking characteristics of the asphalt concrete and omposite structure anti cracking overlay gives a good solution for reflective cracking phenomenon over old cracked pavements.

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Generally speaking,there are two methods for the solution of axially symmetrical elastic space problems in asphalt pavement stress analysis.Integrating the two methods, the authors found out a new form of the general solution of axially symmetrical elastic space problems. Meanwhile, the relationships among the three general solutions of axially symmetrical elastic space problems are obtained, and characteristics of the general solutions are analyzed and compared in the study.

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Backcalculation analysis can be used to find the material properties of pavement. However, most backcalculation programs are based on the linear-elasticity assumption, and the material properties obtained are rarely used for pavement analysis. Laboratory results have shown that pavement materials possess a nonlinear stress-strain relationship. The purpose of this study is to develop a nonlinear backcalculation program which will be used to analyze the properties of the test pavement sections in the Long-Term Pavement Performance (LTPP) database in the United States. The Falling Weight Deflectometer (FWD) test results from these test sections will be compared with the predicted results from linear and nonlinear backcalculation analysis. The backcalculated material properties will also be used to predict the deflections of the FWD test data for different drop weight. Finally, the backcalculation results will be used for the structural analysis.

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Moisture damage can manifest in hot mix asphalt pavements in forms of stripping and softening of asphalt. It results in loss of stability and bearing capacity failure, and rutting of asphalt pavement. One of common anti-stripping additives, hydrated lime (HL), is considered to improve properties of asphalt mixture in resistance of moisture damage. Lime application process can be introduced to asphalt mixture by either adding dry HL to wet aggregates or adding lime slurry to dry aggregates. This study aims to evaluate laboratory performance-based properties of asphalt mixtures using two lime application processes as well as to compare between HL-modified asphalt mixture and polymer-modified asphalt mixture. Results indicated that performance of HL-modified asphalt mixture in moisture damage and rutting is related to lime application processes.

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Highway authority currently face ever-increasing tasks to maintain normal functionality of a huge deteriorated roads. Allocated budget is usually small and covers 30-70% actual needs, thus the necessary maintenance is compulsorily postponed or cancelled. This fact gives us a difficult problem to be solved, whether we should aim for ensuring performance of all highways, or for generating maximum values of maintenance resources. This article therefore presents a computational procedure to prioritize maintenance in accordance with available resources. The priority indices are calculated for highway segments to determine the prioritized works and select scope of maintenance. The priority index is calculated by considering several indicators. The method have been applied to a specific highway network of Vietnam to examine whether it is useful to prioritize most necessary maintenance, such as deteriorated roads whose performance is crucial to the network.

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In existing literature on road alignment optimization, only some cost factors related to the road itself are considered. But actually a new road is not only an isolated transportation facility, but also obviously a component part of a road network. The impact of the new road on the original network is valuable and could not be ignored. In this paper network impact analysis is incorporated into the road alignment optimization model. Each road alternative can change the topology structure of the original network. As for each alternative, flow characteristics of OD traffic on the links are obtained through traffic assignment, and thus changed travel time and environmental load of OD traffic on the network can be estimated. They are converted into monetary equivalents and are regarded as the benefit incurred by the alternative. The ratio of benefit to cost is used as the objective function to evaluate each alternative. Genetic Algorithm is employed to solve this model.

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The purpose of this study was to assess some operational and safety issues related to rural crossing mechanisms: a "traditional" diamond interchange design with roundabout intersections at the ramp termini, and a less conventional design incorporating local roads, called an extended diamond interchange. Various levels of traffic demand were considered through computer simulation. The primary safety metrics were the speed differences between an approaching link and a circulating link (SDAC), and the speed differences between consecutive time windows (SDCW) on an approaching link. In both light and heavy traffic conditions, the extended diamond interchange with roundabouts including local roads seems to be safer, by these metrics, than the typical design because the longer ramp to roundabouts makes traffic flow more stable. For the operational performance, total delay time was surveyed. In heavy traffic conditions, the extended design is stronger than the typical design thanks to more space for vehicle queues.

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The rutting is a major distress mode of the paved road surface. The condition of the rutting is a special concern to road administrators as well as road users because it affects driving safety and ride quality. Nowadays, the maintenance criteria of the road surface are obliged to change from detailed specification to performance specification in response to the road user's demand. However, today in Japan, the rut depth which has been used as an index for the maintenance of the rutting although it has some disadvantages. To establish the index in term of vehicle/road interaction, first, driving experiment at the proving ground is conducted. Then, the new evaluation method of the rutting is proposed based on the vehicle dynamics by use of the Half-Car simulation. As the result, the model indicates the high reproducibility of the rutting effects with a small computational effort.

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Implementing mechanistic empirical pavement design approaches in practice, the need that the pavement performance level related to the limit state function can be controlled considering inherent variabilities associated with design input parameters and systematic bias of the design procedure is being more considerably presented. This paper presents the practical applications of principal reliability concepts to the ME pavement design and introduces a reliability based design approach for the ME flexible pavement design using overall and partial safety factors to design a pavement cross section satisfying performance threshold with a target reliability during its intended design life.

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The deicing work is usually considered as a main part of the highway maintenance activity in during the winter season. The deicing includes the physical method which removes snow with tools and the chemical method which removes the snow with deicing material. When removing snow using deicing material, excessive deicing material will cause the environmental and budget problems. If the deicing materials are used less than the required amount, the snow will remain on the road surface. For these reasons, the adequate usage of deicing materials is important. In this research, the performance of deicing material has been evaluated and the amount of deicing material has been determined according to the amount of snow through the laboratory and the field experiments. Also the adequate usage of deicing material has been determined by 130kg/km-lane on two lane road.

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Portable falling weight deflectometer has been used to evaluate stiffness of subgrade and/or subbase. The stiffness is estimated using a pair of peak values of load and displacement. However, test data is dependent on specification of measurement apparatus. Instead of peak values of load and displacement, this study have used historical time data of load and displacement to estimate layer stiffness. The estimated stiffness was comparable to the one obtained using plate bearing test. The objectives of the study are to improve accuracy on estimated stiffness and to decrease influence of individual apparatus specification.

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The highway cross section slope is an important element in cross section design to drain water and to avoid driver's discomfort. Despite of the importance of the cross slope design, it is not easy to acquire the cross slope geometric information in the field without highway drawings because of the traffic. In many cases, however highway drawings are not always available. Even if we acquire highway drawings, sometimes the drawings are differ from the real-world highway cross section slope because of the frequent pavement overlays. For these reasons, a cross section slope analysis algorithm has been developed which can acquire and analyze the cross slope information using the GPS(Global Positioning System), INS(Inertial Navigation System), and three dimensional laser scanner. The algorithm has been tested to check the possibilities of cross section data collection and analysis quickly along the highway

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The authors have advocated a new planning and design methodology in for highways in Japan, which includes operational performance check in consideration of the traffic demand fluctuation. For this method, it is necessary to reproduce the hourly traffic demand fluctuation on a planned and designed highway section throughout a year. This study proposes a method to reproduce it with two phases; reproducing the daily traffic demand phase and setting the hourly traffic demand coefficient phase, in consideration of potential hourly traffic demand on a day with congestion. The reproduced hourly traffic demand fluctuation using this method was validated on two expressway sections in Japan. As a result, we could verify that the reproduction precision was satisfactory except that it could not consider some special local characteristics.

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In this research, the vertical alignment analysis algorithms was developed which could recognize the highway sections whether they were vertical tangent sections or vertical curve sections using the real-world coordinate data. The developed algorithm for vertical analysis includes the identification of the beginning and ending points of vertical curve sections, the reduction of data noise which are included from the real world coordinates using the Road Safety Survey and Analysis Vehicle(RoSSAV) and the analysis of vertical tangent and curve formula. In order to verify the algorithm, a field test was conducted using the RoSSAV which were installed multiple sensors. The result of field test showed similar output from the analysis algorithm using the acquired coordinates from the RoSSAV comparing with the highway CAD drawing. The analysis algorithm of vertical alignment can be used to substitute highway drawings where highway drawings were not available and can be used to analyze highway safety.

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Based on the analysis of several asphalt mixtures in Indonesia, generally, asphalt mixture has stiffness modulus (E1) varies from 2000 MPa to 5000 MPa. At the subgrade layer, soil has CBR value at 3 percent to 6 percent which is equivalent to modulus (E3) at 30 MPa to 60 MPa. The second layer would be a base layer with thickness considered to be a constant value at 200 mm and stiffness modulus at 100 MPa. The other characteristic is Poisson's Ration (v. Poisson's Ratio for surface (v1), base (v2) and subgrade (v3) was taken as 0.35; 0.40; and 0.45 respectively. Considring the material characteristic above then design nomograph were developed. The nomographs were inspired by Nothingham and there are then 4 types of nomographs related to a subgrade modulus. Pavement thickness result designed using mechanistic procedure was thicker than empirical method.

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Obtaining adequate or optimum binder content is a major requirement in the designing of hot mix asphalt (HMA) pavements. Besides of correct choice of aggregate type, aggregate grading, and bitumen grade, the determination of optimum bitumen content is also important to optimize the engineering properties in relation to the desired behavior in service. This study is conducted to determine the target bitumen content for rubberized porous asphalt prepared by wet and dry mixing process. The target binder content for each sample was determined using binder drainage test adopted from Transport and Road Research Laboratory (TRRL). For both processes, this study found that rubber content was the significant factor affecting the target binder content, which as rubber contents increase, the target binder content increases. The most significant finding is that target binder content for dry process mixes is lower than wet process mixes.

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Semi-Flexible pavement is a composite pavement that utilizes the porous pavement structure of the flexible bituminous pavement which is subsequently grouted with an appropriate cementitious material. The main purpose of this research is to investigate the influence of superplasticizer type and dosage on the flowability of cementitious grouts. The grout mixtures were designed to attain high compressive strength while maintaining flowable properties to ensure that the cement slurries infiltrate easily through the ungrouted samples and to fill up the voids under the influence of gravitational action. In order to attain the workability required, three types of superplasticizer were used. Two were of polycarboxylic ether polymer and the other was of sulphonated naphthalene formaldehyde origin. Results showed that type and dosage of superplasticizer influence the workability of the cementitous grouts.

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Semi-flexible pavement is the combination between the cementitious grouts rigidity and bituminous material flexibility and it was produced from the best qualities of bituminous and concrete component. The main purpose of this study is to concentrate on the design and properties of bituminous mixture to be utilized in the semi-flexible pavement application. The open graded bituminous skeleton was prepared to achieve a compacted porosity between 25% and 30% of the total volume and at the same time maintaining adequate bitumen coating on the aggregates particles. In order to investigate the properties of open graded skeleton, a range of performance and deformation tests were conducted. The tests are porosity, indirect tensile stiffness modulus, compressive strength and cantabro test. The results obtained were compared with porous asphalt skeleton by Zoorob et al. (2002).

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Reinforcement of Bituminous mix might be one of the possible remedies that can be considered to improve the performance of a pavement in terms of rutting resistance. It is thought that the addition of glass fibers to asphalt mixtures enhances material strength and fatigue resistance. This paper investigates some fundamental properties and rutting characteristics of glass fiber reinforced Stone Mastic Asphalt. Laboratory tests in this study comprise the indirect tensile test, creep test and rutting test. Overall the inclusion glass fiber resulted in higher resilient modulus, higher resistance to permanent strain and higher resistance to rutting. Good correlation between the laboratory tests parameters and rutting test. Creep test was found to be more reliable test in evaluating the rutting performance of asphalt mixtures as compared to the IDT test.

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With the rapid growth of population and technology, more and more traditional industries are migrating to hitech systems. Since technology acceptance influent the productivity increment greatly, Technology Acceptance Model was use most frequently to explain and predict acceptance of user to a newly adopted technology. However, the model had few reports on field worker environment, and also, whether perceived behavioral control should be added to the model, are issues worthy of discussion. To clarify the doubts, this paper conducted a survey to 160 road side ticket issuers of Taipei city parking administration, who recently changed their issuing system from paper and pen to PDA. The 15 item questionnaire is adopted form literature and the results of focus group meetings and a small scale pre-test. The data collected were analyzed with SEM method, discussion and future research directions are also provided.

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In cementitious grout as required for semi-rigid pavement, pozzolanic materials are used as supplementary cementitious materials to improve its properties. Pozzolanic material affects strength and other properties of grout such as flow, strength and density. This study is aimed at exploring the effects of silica fume and fly ash on the characteristics of cementitious grout through laboratory experiments. The cementitious grout used in this study is composed of ordinary Portland cement(OPC), Silica flume or Fly ash mixed with water and chemical admixture of superplasticizer. The prepared grouts are tested for the properties such as flow time, compressive strength and density. The effects of combined addition of SF and SP or fly ash and SP combinations on grout strength, flow and density are explored. It is found that flow times and strengths are significantly affected for addition or replacement of fly ash and silica fume in the OPC mix.

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The use of double layer porous asphalt (DLPA) to reduce highway noise was the focus of a scanning tour to the Netherlands. A visit was also conducted to the Belgian Road Research Centre. The Dutch Innovatieprogramma Geluid program has strategised policies that set noise level thresholds and seek noise reductions from both vehicles and tyres. The DLPA, regarded as a potential noise reducing pavement material, comprised of a thin finer porous asphalt underlying a coarser but thicker bottom layer can potentially reduce traffic noise by up to 6 dB(A). Construction wise, DLPA has to be placed hot-on-hot to avoid rapid cooling of the thin top layer. The results of a CT scan on DLPA revealed that the transition zone crucially dictated mix porosity hence permeability. Experience with DLPA in Belgium was rather recent with one trial site at Bambois.

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In Korea, the condition of road markings is not systematically recorded or evaluated, and thus, it is hard to manage or make decisions regarding the matter. This study undertakes a field research and analyzes retroreflective performance of road markings installed along the national highways in Korea. The study evaluates suitability of standards for road markings, identifies related problems, and seeks solutions.

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Thailand has a highway network of about 160,000 kilometres, 52,500 of which are main highways under the responsibility of Department of Highways. In its recent approach to road asset management, DOH engaged four leading Thai universities to upgrade existing Thailand Pavement Management System and introduce HDM4 for use in its pavement management programme. The new approach uses automated data collection of highway conditions which include rutting, pavement roughness and surface distresses. This paper describes the application of a survey vehicle equipped with laser profilers, digital video cameras, distance measuring instrument and others in data collection of highway conditions, asset views, and pavement views and use of HDM4 in strategic assessment of funding needs and optimum resource allocation for pavement management at the project and network levels.

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Social conflict related to highway construction in Korea is continuously increasing. As a result, interest, research, and policy-making related to public involvement (PI) have also been increasing. The government has created committees and regulations to find ways to effectively manage conflict. In the highway planning process, opportunities for public debate are extremely limited and come only at the end of the planning process. A successful, ongoing demonstration PI project for the planning of the Chuncheon-Yangyang Expressway has expanded the capability and tools of Korea's highway agencies for involving the public. A PI manual is being developed simultaneously. However, the PI demonstration project also illustrated that PI still started too late in the planning process and that the process still fell short of processes used in Japan and the US. Further, carefully considered legislation will be necessary in order to implement truly effective PI.

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In this paper, we presented a method of building the view image for driving simulator by applying the photographic measurement, based on various road distresses such as cracks, rutting and roughness of the road surface. The method is using a digital camera to obtain the photograph on the road, and then convert the image data into the profile data of three-dimensions. As a result, running environment in an actual road can be created by inputting the three-dimensional profile data to driving simulator, and by reproducing the road image corresponding to this at the same time. The main property of this method is can obtain the data profile from several photographs of the road. Therefore, it is flexible and efficient, especially when the measurements of the road properties have the difficulty due to heavy traffic conditions. Another advantage of this method is economical and easy to implement.

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Urban sprawl along arterial road is a common phenomenon in Bangkok. This pattern of urban growth has resulted in uncontrolled access to the arterial road. The most common way to handle the traffic changing to the opposite direction of the road is to provide median openings, which adversely affects road capacity. This study is aimed to investigate the effects of u-turn traffic on road capacity and lane utilization. Video cameras were used to record the traffic data of a median opening on a major arterial in Bangkok. Regression analysis indicated that at the median opening, capacity of the middle lane is approximately equivalent to 1,680 pcu/h. while the observed capacity is 1,896 pcu/h. It is found that share of traffic in the middle lane remains almost unchanged at above 50 percent throughout the study road section. PCEs for motorcycle, passenger car and truck making u-turn movement are also estimated.

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To protect pedestrians, bicyclists, and the quality of living environment, vertical and horizontal speed reduction devices (SRD) are often utilized to reduce the vehicle speed. SRDs not only contribute to reducing vehicle speed, but also redistribute the traffic flow due to the change of travel time which implies the residents have also to endure the inconvenience of SRD. To help evaluate the SRD installation, this study uses the traffic flow-speed-density relationship setting the minimum travel time as the objective function to establish a steady state traffic assignment model. Different traffic settings and SRD installation schemes are tested and evaluated which shows that the introduction of SRD is most significant when traffic outside the traffic calming zone is at high volume peak period. By proper choice of SRD type and installation scheme, through traffic outside the community cutting into the local streets can be significantly reduced.

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This paper presents nonparametric generalized additive models to detect both lane-blocking and shoulder incidents for two freeways in Colorado and California, USA. The parametric generalized additive models were developed based on the examination of the partial prediction of the variables of the nonparametric generalized additive model. This paper also highlights the importance of developing incident detection models to detect both lane-blocking and shoulder incidents. The performance of the nonparametric generalized additive models were also compared to multilayer feedforward neural network based models.

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Advanced Traffic Control Systems (ATCS) have been used to ease transportation problems in large cities around the world. The application of ATCS in developing countries is noteworthy, because these cities face more severe transportation problems and characterised by typologies. The aim of this study is to evaluate the performance of ATCS in different type of typologies. A large road network in Bandung, Indonesia was used as a case study. Hierarchical Cluster analysis was used to classify the Bandung road network into typologies. AIMSUN micro-simulator was used to evaluate the performance of ATCS at each typology. The results showed that based on typologies, the application of ATCS in the large city in a developing country was ineffective to increase traffic performance measures especially during morning peak period and in typology consists of intersections with medium to large size, lied in CBD area, and have high level of side friction.

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Mixed road traffic with a high proportion of motorcycles, which is a typical vehicle composition in Hochiminh City and other cities in Vietnam. Due to the nature of such a traffic stream, the method commonly used in evaluating traffic signals cannot be adopted here. Motorcycles are performing differently to traffic signals compared with passenger cars; in particular, their advanced mobility and flexibility resulted in a failure of the application of traditional traffic signal evaluation tools. This paper attempts to report a new approach for the issue; using a modified Passenger Car Equivalent unit (PCE) to convert the number of motorcycles into standard car unit. Then aaSIDRA is applied to conduct a standard evaluation process on the performance of traffic signal designs; a range of output from aaSIDRA can be used to compare the differences with different signal settings.

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The activities of detection, classification, and surveillance of traffic are critical to the efficient operation of streets and highways. Well development of vehicle detection and vehicle classification can not only supplement police efforts but also provide uniform enforcement to enforce against noncompliance with traffic law. In order to reduce manpower for the traffic police, this paper aims at developing an advanced intelligent enforcement system which incorporates laser range imaging system, image tracking system, enforcement expert system, and license plate reading system. The core logics of the proposed enforcement expert system was analyzed, including which vehicle detection and vehicle classification techniques can be used to perform which traffic rules, e.g. abnormal turning. We expected that the advanced intelligent enforcement system will be performed in the role of the traffic police cracking down on traffic violators.

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Prediction of travel times is a vital part of many advanced traveler information systems. Linear model is used in this research as it is effective, computationally efficient and reliable to the available freeway detector data. In this paper an explicit analysis of the linear model is shown and a method to predict freeway travel times using a linear model is proposed. The proposed method is applied to a data set of Hanshin Expressway, Japan.

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Over time there will be inevitable changes in the travel demand patterns in a transport network. To capture these changing demands and design a gradually upgraded network it is necessary to introduce the time dimension into the transport Network Design Problem (NDP). Previous efforts have extended the continuous network design problem to cater for such considerations. However the continuous problem does not always indicate improvements that are practical. Therefore in this paper we develop a model of the time-dependent discrete network design problem. The importance of the model is illustrated by two numerical studies, which demonstrate the importance of introducing the time dimension to the NDP and the importance of introducing discrete decision variables to the NDP over time. An example on NDP under two cost-recovery principles is also provided to illustrate the application of the model.

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This paper proposes a novel filtering approach to scrutinize the characteristics of traffic flow dynamics measured in various time intervals during different times of day at different detection stations. The proposed approach executes stepwise procedures to filter out quasi (periodic) time series by Fourier power spectrum, equilibrium fixed points by the largest Lyapunov exponent, randomness by iterated function system (IFS) clumpiness maps, and followed by distinguishing chaoticity and stochasticity by correlation dimension. The numerical study analyzes the properties of dynamic traffic flows of four detection stations, sampled, respectively, in 20-second, one-minute, three-minute and nine-minute intervals, measured during midnight, morning, afternoon and evening periods. The results indicate that different nonlinear patterns, including fixed points, randomness, and chaotic-like phenomena may exist irregularly, contingent on the measured time intervals and observed times of day.

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By applying the concept of information entropy in the information theory, this study aims to create a complexity index to measure the driver-perceived driving environment and to give remedy for the past indexes' incapability of showing drivers' perceived comfort and safety. The complexity index is calculated by the drivers' driving behaviors of speed, acceleration and deceleration, and horizontal shift area. We show that the complexity index is a proper qualitative index to truly reflect the drivers' perception of driving environment and to measure the level of service. It can be a supplement index for the traditional traffic measures.

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Increased economic activities and improvements in quality of life have resulted in a corresponding increase in human and material traffic across existing transport networks. Hence, there is a need for examining the reliability of these networks. The main objective of this study is to examine travel time reliability of various sections in the Han-Shin expressway network Osaka and Kobe area. Performed travel time reliability evaluation of each route considered in this study. To do this, various existing travel time reliability indices are considered and are examined. The advantage of travel time reliability is that, it can be used in policy assessment as a new evaluation technique and also may be used as travel time related information to the system users. Further in this study, conventional congestion measures presently using a measuring performance of Han-shin expressway network are compared with travel time reliability measures. Results reveal that reliability measures are more capable of measuring the variability in congestion level.

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