Study on traffic organization design of expressways with heavy traffic flow during occupying-road construction

Bitumen is widely used in road construction. Due to heavy traffic loads and environmental factors, bitumen properties will change during service life. Bitumen will age due to diffusion of oxygen and UV radiation. Repeated loading will result in decreasing strength because of fatigue. In this paper, one layer clay powder was used to modify base bitumen with different mass contents. Then the influences of ultraviolet radiation (UV) aging on the dynamic fatigue properties of the layered clay powder were evaluated by Dynamic Shear Rheomoter (DSR) and Universal Testing Machine (UTM). The ageing evaluation shows that the ageing resistance of bitumen is improved and this improvement is more notable in bitumen fatigue than mixture.

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Organization Optimization of Traffic Engineering in Urban CBD

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.579-580.890 ◽

2013 ◽

Vol 579-580 ◽

pp. 890-893

Author(s):

Mei Mei Huang ◽

Qing Yang ◽

Shang Lin Xiao

Keyword(s):

Traffic Flow ◽

Traffic Engineering ◽

Queue Length ◽

Motor Vehicle ◽

Heavy Traffic ◽

Optimization Methods ◽

Difficult Problem ◽

Signal Timing ◽

Total Capacity ◽

Business District

Orderly organization of traffic engineering in the urban CBD (Center Business District) is a difficult problem, with crowding people flow, heavy traffic flow and complex surrounding situation. This paper set CBD along Xinhua Street in Jinhua city center as an example, focused on the organization optimization process of traffic engineering in CBD. Through the survey on traffic engineering status of sections and intersections, it analyzed road congestion characteristics and intersection signal timing with Vissim software emulation, proposed traffic optimization methods as road channelization, intersection signal timing adjustment of Xinhua-Liberation Road. In Xinhua Street section, it can effectively canalized traffic flow by broadening 2 two-way lanes, adding four pedestrian crossing refuges, and separating Motor vehicle and non-motor vehicle separation barrier. It took queue length, number of stops, delay time three indicators as the objective function with the application of Synchro software adjusting the intersection signal timing. As a result, the total queue length could be reduced from 708.5m to 586.6m and total capacity from 2041 pcu/ h to 2838 pcu/ h.

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A Dynamic Traffic Assignment Model for the Sustainability of Pavement Performance

Sustainability ◽

10.3390/su11010170 ◽

2018 ◽

Vol 11 (1) ◽

pp. 170 ◽

Cited By ~ 9

Author(s):

Xinhua Mao ◽

Jianwei Wang ◽

Changwei Yuan ◽

Wei Yu ◽

Jiahua Gan

Keyword(s):

Travel Time ◽

Traffic Flow ◽

Traffic Assignment ◽

Dynamic Traffic Assignment ◽

Heavy Traffic ◽

Pollutant Emissions ◽

Pavement Performance ◽

Dynamic Traffic ◽

Teaching Learning ◽

Pavement Damage

Existing Dynamic Traffic Assignment (DTA) models assign traffic flow with the principle of travel time, which are easy to distribute most of the traffic flows on the shortest path. A serious unbalance of traffic flow in the network can speed up pavement deterioration of highways with heavy traffic, which influences the sustainability of pavement performance and increases maintenance expenditures. The purpose of this research is to obtain a more optimized traffic assignment for pavement damage reduction by establishing a multi-objective DTA model with the objectives of not only minimum travel time but minimum decline of Present Serviceability Index (PSI) for pavements. Then, teaching-learning-based optimization (TLBO) algorithm is utilized to solve the proposed model. Results of a case study indicate that a more balanced traffic flow assignment can be realized by the model, which can effectively reduce average PSI loss, save maintenance expenditures, extend pavement service life span, save fuel consumption and reduce pollutant emissions in spite of a little increase of average travel time. Additionally, sensitivity of weight factor for the two objective functions is analyzed. This research provides some insights on methods on sustainable pavement performance.

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ANALYSIS AND MODELING TIME HEADWAY DISTRIBUTIONS UNDER HEAVY TRAFFIC FLOW CONDITIONS IN THE URBAN HIGHWAYS: CASE OF ISFAHAN

Transport ◽

10.3846/16484142.2011.635694 ◽

2012 ◽

Vol 26 (4) ◽

pp. 375-382 ◽

Cited By ~ 19

Author(s):

Sayyed Mahdi Abtahi ◽

Mohammad Tamannaei ◽

Hosein Haghshenash

Keyword(s):

Traffic Flow ◽

Heavy Traffic ◽

Distribution Analysis ◽

Distribution Models ◽

Chi Square ◽

Time Headway ◽

Headway Distribution ◽

Chi Square Test ◽

Lane Position ◽

Highway Facilities

The time headway of vehicles is an important microscopic traffic flow parameter which affects the safety and capacity of highway facilities such as freeways and multi-lane highways. The present paper intends to provide a report on the results of a study aimed at investigating the effect of the lane position on time headway distributions within the high levels of traffic flow. The main issue of this study is to assess the driver's behavior at different highway lanes based on a headway distribution analysis. The study was conducted in the city of Isfahan, Iran. Shahid Kharrazi six-lane highway was selected for collecting the field headway data. The under-study lanes consisted of passing and middle lanes. The appropriate models of headway distributions were selected using a methodology based on Chi-Square test for each lane. Using the selected models, the headway distribution diagrams were predicted for high levels of traffic flow in both the passing and middle lanes and the relationship between statistical criteria of the models and the driver's behaviors were analyzed. The results certify that the appropriate model for the passing lane is different than the one for the middle lane. This is because of a different behavioral operation of drivers which is affected by specific conditions of each lane. Through car-following conditions in the passing lane, a large number of drivers adopt unsafe headways. This shows high risk-ability of driver population which led to considerably differences in capacities and statistical distribution models of two lanes.

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Land-Saving Mode of Congo (Brazzaville) Highway One (Phase II)

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.256-259.1832 ◽

2012 ◽

Vol 256-259 ◽

pp. 1832-1836

Author(s):

Jing Shi ◽

Jin Hua Tan ◽

Nian Zhou

Keyword(s):

Service Life ◽

Literature Review ◽

Traffic Flow ◽

Phase Ii ◽

Road Construction ◽

Cultivated Land ◽

Turning Radius ◽

Saving Mode ◽

Congo Brazzaville ◽

Land Saving

Plenty of cultivated land has been used for highway construction. Thus Land-saving mode in road construction has drawn more and more attentions. However, inappropriate land-saving mode may result in some kinds of risks during highway's service life. Based on road risk, this paper discusses land-saving mode of Congo (Brazzaville) Highway One (Phase Ⅱ), trying to reach the balance between the two after accomplishing literature review and analyzing the prediction of traffic flow. The result shows that, the project should choose the mode such as proper construction scale and high bridge & tunnel ratio, rather than small turning radius and low roadbed.

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An Evaluation Model for Traffic Guidance Measures of the Urban Central Commercial District and its Application

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.253-255.1695 ◽

2012 ◽

Vol 253-255 ◽

pp. 1695-1699

Author(s):

Miao Cui ◽

Tie Xin Cheng ◽

Jing Zhu Chen

Keyword(s):

Traffic Flow ◽

Evaluation Model ◽

Heavy Traffic ◽

Simulation Software ◽

Left Turn ◽

Traffic Jam ◽

The Road ◽

Dynamic Assignment ◽

Assignment Model ◽

Traffic Guidance

As the city’s economic and cultural center, the urban Central Commercial Districts (CCDs) are rapidly developing, which always brings the heavy traffic jam in the city. In this paper, the traffic flow of CCDs was analyzed, and the traffic flow guidance evaluation model was established. Firstly, according to the travel time function, traffic flow was allocated to the road network of the CCDs by the dynamic assignment model, and the heavy-traffic roads were identified. Then, traffic flow guidance measures mainly including forbidding straight, left turn, or right turn were given, and the evaluation model above was applied to select the optimal measure. Finally, with VISSIM simulation software, the model was applied to the Tianjin Binjiangdao CCD, which illustrated that the satisfied guidance measure can be selected effectively.

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A SHORT REVIEW ON USING CRUMB RUBBER AS MODIFICATION OF BITUMEN BINDER

Jurnal Teknologi ◽

10.11113/jt.v78.9479 ◽

2016 ◽

Vol 78 (7-3) ◽

Author(s):

Md. Maniruzzaman A. Aziz ◽

Zohair Ahmed Altieb ◽

Khairul Anuar Bin Kassim ◽

Hauwa Baffa Jibrin

Keyword(s):

Heavy Traffic ◽

Influencing Factor ◽

Road Construction ◽

Short Review ◽

Crumb Rubber ◽

High Viscosity ◽

Wet Process ◽

Physical Tests ◽

On The Road ◽

Waste Crumb Rubber

The increasing consumption of waste tire has generated many problems such as increasing landfill space, environmental pollution and causing health hazards. Parallel to this is the increasing of roads construction as a result of heavy traffic on roads. This study reviews to the use of crumb rubber (waste tires in powder form) in bitumen using the wet process. The study focuses on the crumb rubber as a replacement to the total weight of bitumen. The design or life span for all highways and urban roads is 10 – 20 years. Unfortunately, damages or distresses on pavements are still occurring before reaching the maximum period of the designed road serviceability. Among the major influencing factor that is contributing to this distress is the repeated heavy traffic loading on the road surfaces. Moreover, the use of waste crumb rubber in road construction as a pavement surface has a better skid resistance, fatigue crack resistance and increased rut resistance. The review includes physical tests that are used to determine the physical properties of bitumen and modified crumb rubber mix. The physical tests involve penetration test, softening point test and viscosity test. The second stage is rheological tests like rolling thin film oven test (RTFOT), pressure aging vessel (PAV) and dynamic shear rheometer (DSR) tests. The expectations from the study are to develop bitumen with waste crumb rubber that would minimize the costs of bitumen and providing better physical and rheological properties compared to the convention bitumen based on the tests that was conducted. Crumb rubber modifier as improved resistance to rutting due to high viscosity, Improved resistance to surface initiated, reduce fatigue/ reflection cracking, lower pavement maintenance costs, and saving in energy and natural resource.

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Study on the Traffic Capacity of Expressway Based on Cellular Automata Model

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.701-702.172 ◽

2014 ◽

Vol 701-702 ◽

pp. 172-179

Author(s):

Xiao Dong Xia ◽

Lin Ling Xu

Keyword(s):

Cellular Automata ◽

Traffic Flow ◽

Heavy Traffic ◽

Accident Rate ◽

Cellular Automata Model ◽

Traffic Capacity ◽

Low Load ◽

The Right ◽

The Relationship ◽

Shape Changes

Based on the Nagel-Schrekenberg cellular automaton model of traffic flow, this article analyzed the influence that driving on the right side takes to the traffic flow in the condition of light and heavy traffic. With the combination of fluid dynamics and vehicle dynamics, we established the Cellular Automata model for mixed speed two-lane traffic flow on the rule driving on the right side. Then we used the AHP method to find out the large bus share rate, the number of vehicles changing lanes and the influence law of safety factors on traffic flow. We came to a conclusion that the relationship between traffic flow and load are inverted U shape changes in the low load and high load conditions, the accident rate is the maximum when the V/C (the ratio of traffic flow and the ability of corresponding section) is the minimum; with the increase of V/C, the accident rate decreased gradually.

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Intersection and Passageway Designs of Urban Agglomeration Connection Road

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.361-363.2330 ◽

2013 ◽

Vol 361-363 ◽

pp. 2330-2338

Author(s):

Yu Ming Zhou ◽

Jin Liang Xu ◽

Hong Zhi Yang ◽

Yue Jie Han ◽

Fang Li

Keyword(s):

Traffic Congestion ◽

Queue Length ◽

Pearl River Delta ◽

Organization Design ◽

Urban Agglomeration ◽

Running Speed ◽

Left Turn ◽

Traffic Characteristics ◽

Function Design ◽

Traffic Organization

To study the design rationality of intersection and gateways, reduce traffic congestion and accidents, based on the function design conception,this paper took connected roads in Pearl River Delta urban agglomeration as research object, combined theoretical analysis and VISSIM simulations, analyzed the traffic characteristics, reasonable forms, traffic organization design methods in the intersections, as well as the locations and reasonable intervals of passageways. The results show that: length of left-turn lanes on city agglomeration connection roads can be 40m to100m, while the length of right-turn lanes for acceleration or deceleration can be 40m~60m. When the distance between two gateways ranges is 800m~900m, the running speed will increase obviously and the longest queue length will decrease remarkably; But when it is over 900m, the variation of running speed and queue length will change to be smaller.So the distance recommended value is 900m-1200m.

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