scholarly journals Resilience Assessment of a Twin-Tube Motorway Tunnel in the Event of a Traffic Accident or Fire in a Tube

2022 ◽  
Vol 12 (1) ◽  
pp. 513
Author(s):  
Ciro Caliendo ◽  
Isidoro Russo ◽  
Gianluca Genovese
Keyword(s):  
Travel Time ◽  
Traffic Flow ◽  
Traffic Accident ◽  
Negative Effects ◽  
Passenger Cars ◽  
Support Tool ◽  
Complete Closure ◽  
Closed Tube ◽  
Time Required ◽  
Message Signs

We have developed a traffic simulation model to quantitatively assess the resilience of a twin-tube motorway tunnel in the event of traffic accident or fire occurring within a tube. The motorway section containing the tunnel was investigated for different possible scenarios including its partial or complete closure. The functionality of the road infrastructure, in the case of an accident in one of the two tubes (each tube presents two lanes with unidirectional traffic under ordinary conditions), was assumed to be recovered both by using the remaining undisrupted lane of the tube interested by the disruptive event (only one lane is closed) and reorganizing the traffic flow by utilizing the adjacent tube for bi-directional traffic (both lanes are closed). The effects of an alternative itinerary individualized in the corresponding open road network were also examined. The level of functionality of the system during the period in which the tube is partially or completely closed was computed as the ratio between the average travel time required to reach a given destination from a specific origin before and after the occurrence of the disruptive event. The resilience metrics were assumed to be resilience loss, recovery speed, and resilience index. The best scenario was found to be the partial closure of the tube in contrast to the complete one. However, in order to contain the negative effects on the functionality of the motorway section due to the complete closure of the tube, it is worth highlighting how the traffic by-pass before the entrance portal of the closed tube should be open in a very short time by the tunnel management team to allow for the quick use of the adjacent tube for bi-directional traffic. An additional improvement, with reference exclusively to passenger cars traveling through the adjacent unblocked tube, might be obtained by activating the variable message signs, located at a sufficient distance from the motorway junction before the entrance portal of the closed tube, in order to suggest an alternative route to heavy good vehicles (HGVs) only. Whereas, when the alternative itinerary is used by all vehicles traveling towards the blocked tube (i.e., both passenger cars and HGVs), this redirectioning of the motorway traffic flow was found to be characterized by an excessive travel time, with it therefore not being advisable. The results obtained might be useful as a decision-making support tool aimed at improving the resilience of twin-tube tunnels.

scholarly journals Review, Experimental Evaluation and Policy Considerations of a Directional Time of Day Truck Restriction on Highways

2015 ◽  
Author(s):  
Shy Bassan
Keyword(s):  
Travel Time ◽  
Traffic Flow ◽  
Time Of Day ◽  
Truck Traffic ◽  
Passenger Cars ◽  
Traffic Efficiency ◽  
Flow Parameters ◽  
Time Period ◽  
Traffic Stream ◽  
Total Travel Time

The paper reviews several strategies of restricting or separating trucks from the regular traffic stream. Typical truck restriction policies focus on leftmost lanes restriction, which has been shown by several studies to have some advantages. However, those studies clearly show that vehicle queue lengths in the vicinity of critical merging areas increase significantly as the percentage of trucks increases. Therefore, this study examines a different policy—one which investigates traffic efficiency gained by restricting heavy truck traffic in one direction—in this case, westbound on Highway 1 in Israel—during afternoon peak hours. Similar policies of utilizing a specific vehicle category (e.g. passenger cars or trucks) in different daily time periods or physical separation of homogenous traffic of passenger cars in the inner lanes and mixed traffic in the outer lanes, were recommended in Italian motorways and in New Jersey Turnpike dual-dual freeways respectively.Highway 1 is a freeway connecting Jerusalem and Tel Aviv that passes by Ben-Gurion International Airport. The major objective of this study is to estimate the benefit of restricting truck traffic in the traffic stream according to three traffic-flow parameters: average travel time, total travel time, and average traffic speed. Analysis of the results, which consider the significant differences of 30-minute time period samples (“before-after” truck restriction), shows that prohibiting trucks in all lanes in one direction during the peak afternoon period of 16:00-18:00 improved all three traffic flow parameters by 8%-12%. Generally a steep grade from which truck traffic is banned is correlated with an improvement in traffic flow. In our case, Highway 1 road segments 1 and 2 and 4, which have steep grades (longitudinal grades), incorporated the most significant improvements in the traffic stream parameters examined.

Evaluation Results of the Amsterdam, Netherlands, Practical Trial with In-Car Travel and Route Advice

2017 ◽  
Vol 2621 (1) ◽  
pp. 38-45 ◽  
Author(s):  
Isabel Wilmink ◽  
Eline Jonkers ◽  
Maaike Snelder ◽  
Gerdien Klunder
Keyword(s):  
Travel Time ◽  
Traffic Flow ◽  
Large Scale ◽  
User Behavior ◽  
Route Guidance ◽  
Travel Times ◽  
Guidance Services ◽  
Social Navigation ◽  
Total Travel Time ◽  
Message Signs

Travel and route guidance services are widely available. Social navigation services that provide travelers with advice aimed at minimizing driver travel time, while also taking into account the effect on travel times of other travelers, are relatively new. Theoretically, social navigation has been shown to reduce total travel time by 10% to 30%. This paper presents the evaluation results of a large-scale field trial for pretrip and on-trip route advice with load balancing, in which about 20,000 participants were active. The evaluation provided insight into the potential effects of in-car information services, such as effects on user behavior, traffic flow effects, and technical aspects. Participants used mostly the pretrip advisories. Compliance with the on-trip route advice was 50%, which was considered high (compared with compliance with route advice on variable message signs). An effect on traffic flow could not be measured, as penetration rates were (despite thousands of users) still too low. An offline study using measured travel times combined with a traffic model, however, showed that substantial delay reductions can be achieved for the Amsterdam, Netherlands, region. Participants’ appreciation of the service resulted in a mixed picture with positive and negative ratings. The main practical contribution of this paper is that the results can be used to develop social navigation services. Empirical insights about route advice compliance can be seen as the main scientific contribution.

ENSURING THE PEDESTRIAN’S SAFETY DESIGN OF URBAN STREET CROSSWALKS

2019 ◽  
pp. 103-110
Author(s):  
Dmitriy Nemchinov
Keyword(s):  
Traffic Flow ◽  
Minimum Distance ◽  
Travel Speed ◽  
Vehicle Speed ◽  
Urban Street ◽  
Safety Design ◽  
Positive Practices ◽  
Time Required ◽  
Pedestrian Crossing ◽  
The City

The article presents an analysis of positive practices for ensuring the safety of pedestrians at the inter-section of the city streets carriageway, as well as a description of some innovations of regulatory and tech-nical documents, including an increased number of cases when a safety island can be arranged at a pedestri-an crossing. requirements for providing visibility at a pedestrian crossing to determine the minimum distance of visibility at a pedestrian crossing based on the time required pedestrians for crossing the roadway, recommended options for using ground unregulated pedestrian crossings on trapezoidal artificial irregularities according to GOST R 52605; traffic flow) and Z-shaped (also in the direction of the traffic flow), the requirements for the size of the securi-ty island have been established to allow put bicycle inside of safety island, a recommended set of measures to reduce the vehicle speed and describes the types of activities and describes a method of their application, describes methods zones device with reduced travel speed - residential and school zones, set requirements for turboroundabouts and methods of their design.

Finite mixture survival model for examining the variability of urban arterial travel time for buses, passenger cars and taxis

2020 ◽  
Vol 14 (12) ◽  
pp. 1524-1533 ◽  
Author(s):  
Xinzhi Zhong ◽  
Yajie Zou ◽  
Zhi Dong ◽  
Shaoxin Yuan ◽  
Muhammad Ijaz
Keyword(s):  
Travel Time ◽  
Survival Model ◽  
Finite Mixture ◽  
Passenger Cars ◽  
Urban Arterial

scholarly journals EVALUATING THE EFFECT OF HEAVY VEHICLES ON TRAFFIC PARAMETERS BY USING HEAVY VEHICLE FACTOR

2018 ◽  
Vol 6 (4) ◽  
pp. 95-104
Author(s):  
Parthkumar Patel ◽  
H.R. Varia
Keyword(s):  
Travel Time ◽  
Traffic Flow ◽  
Road Traffic ◽  
Freight Transport ◽  
Heavy Vehicle ◽  
Mixed Traffic ◽  
Heavy Vehicles ◽  
Highway Traffic ◽  
Ideal Situation ◽  
The Impact

Safe, convenient and timely transportation of goods and passengers is necessary for development of nation. After independence road traffic is increased manifold in India. Modal share of freight transport is shifted from Railway to roadways in India. Road infrastructures continuously increased from past few decades but there is still need for new roads to be build and more than three forth of the roads having mixed traffic plying on it. The impact of freight vehicles on highway traffic is enormous as they are moving with slow speeds. Nature of traffic flow is dependent on various traffic parameters such as speed, density, volume and travel time etc. As per ideal situation these traffic parameters should remain intact, but it is greatly affected by presence of heavy vehicle in mixed traffic due to Svehicles plying on two lane roads. Heavy vehicles affect the traffic flow because of their length and size and acceleration/deceleration characteristics.  This study is aimed to analyse the impact of heavy vehicles on traffic parameters.

scholarly journals Warehouse Relayout Design with Weighted Distance Method to Minimize Time Travel

2020 ◽  
Vol 3 (1) ◽  
pp. 1-8
Author(s):  
Adi Firmansyah ◽  
Lukmandono Lukmandono
Keyword(s):  
Mathematical Model ◽  
Travel Time ◽  
Layout Design ◽  
Global Competition ◽  
Closing Time ◽  
Distance Method ◽  
Weighted Distance ◽  
Logistics Services ◽  
Time Required ◽  
Efficient Work

Global competition between companies is becoming increasingly stringent, resulting in companies having to understand their customers better. Customers no longer only need quality products, but also need excellent and timely service. To meet the desires of these consumers, the company must create an effective and efficient work system. PT IJS is a warehouse engaged in logistics services in the Perak area of Surabaya. One of the services provided by PT IJS is bonded warehouse logistic services. A bounded warehouse owned is currently not able to provide maximum service because there are still many late deliveries that do not send goods to the port, and there is a closing time that is detrimental to the customer. The length of the delivery process is due to several factors, one of which is a less effective warehouse layout. Travel time is the time required for a vehicle to carry out activities loading goods PT. IJS from arrival to exit the warehouse. The method weighted distance is a mathematical model used to evaluate the layout based on proximity factors. The design of the layout design by using the technique weighted distance produces an alternative layout that shows calculation travel time a shorter

Exploring Multiplier Effects Generated by Bus Lane Combinations

2015 ◽  
Vol 2533 (1) ◽  
pp. 68-77 ◽  
Author(s):  
Long Tien Truong ◽  
Majid Sarvi ◽  
Graham Currie
Keyword(s):  
Travel Time ◽  
Traffic Volume ◽  
Policy Implications ◽  
Future Research ◽  
Negative Effects ◽  
Bus Priority ◽  
Traffic Lane ◽  
Multiplier Effect ◽  
Bus Lane ◽  
Multiplier Effects

Numerous studies have explored design and evaluation of bus lane priority by using empirical, analytical, and simulation approaches. However, none attempted to understand how different bus lane combinations, such as continuous and discontinuous bus lane sections, and a different number of bus lane sections, affect bus performance and general traffic. This paper investigates operational effects of bus lane combinations to establish whether multiple bus lane sections create a multiplier effect in which a series of continuous bus lane sections creates more benefits than several single-lane sections. If a multiplier effect exists, it suggests scale economies in wider implementation of bus priority on a networkwide scale. Overall, results confirm that there is a multiplier effect; thus bus travel time benefits and general traffic travel time disbenefits are proportional to the number of links with a bus lane. The effect suggests a constant return to scale on continuous multiple sections. The results also suggest that converting a traffic lane to a bus lane when the upstream traffic volume exceeds the capacity of the remaining traffic lanes causes significant negative effects for buses and general traffic. In addition, negative general traffic effects of continuous bus lane combinations are lower than those for a similar number of discontinuous bus lanes. Bus delays at intersections approaching the bus lane tend to improve when upstream traffic volume does not exceed the capacity of remaining downstream traffic lanes. Policy implications and areas for future research are suggested.

scholarly journals Prioritizing Safety or Traffic Flow? Qualitative Study on Highly Automated Vehicles’ Potential to Prevent Pedestrian Crashes with Two Different Ambitions

2020 ◽  
Vol 12 (8) ◽  
pp. 3206
Author(s):  
Roni Utriainen ◽  
Markus Pöllänen
Keyword(s):  
Qualitative Study ◽  
Traffic Flow ◽  
Pedestrian Safety ◽  
Automated Vehicles ◽  
Passenger Cars ◽  
High Expectations ◽  
Fatal Crashes ◽  
Pedestrian Crashes

Interaction between drivers and pedestrians enables pedestrians to cross the street without conflicts. When highly automated vehicles (HAVs) become prevalent, interaction will change. Although HAVs manage to identify pedestrians, they may not be able to assess pedestrians’ intentions. This study discusses two different ambitions: Prioritizing pedestrian safety and prioritizing efficient traffic flow; and how these two affect the possibilities to avoid fatal crashes between pedestrians and passenger cars. HAVs’ hypothetical possibilities to avoid different crash scenarios are evaluated based on 40 in-depth investigated fatal pedestrian crashes, which occurred with manually-driven cars in Finland in 2014–2016. When HAVs prioritize pedestrian safety, they decrease speed near pedestrians as a precaution which affects traffic flow due to frequent decelerations. When HAVs prioritize efficient traffic flow, they only decelerate, when pedestrians are in a collision course. The study shows that neither of these approaches can be applied in all traffic environments, and all of the studied crashes would not likely be avoidable with HAVs even when prioritizing pedestrian safety. The high expectations of HAVs’ safety benefits may not be realized, and in addition to safety and traffic flow, there are many other objectives in traffic which need to be considered.

Computer-Based Perspective Broadening Support for Appraisal Training

2020 ◽  
Vol 16 (3) ◽  
pp. 86-108
Author(s):  
Ursula M. Beer ◽  
Mark A. Neerincx ◽  
Nexhmedin Morina ◽  
Willem-Paul Brinkman
Keyword(s):  
Traumatic Event ◽  
Post Traumatic Stress ◽  
Negative Effects ◽  
Student Sample ◽  
Support Tool ◽  
Technological Support ◽  
Multiple Outcome ◽  
Computer Based ◽  
Post Traumatic ◽  
Effect Of The Support

Post-traumatic stress affects millions of people worldwide. Appraisal training is an intervention that has been used to decrease the negative effects of a traumatic event. In two studies, the acceptance and effects of technology in supporting appraisal was studied. Study 1, a descriptive study, examined the response to and acceptance of a workshop on perspective broadening with technological support among soldiers and firefighters. Results revealed that both groups evaluated the training as useful and feasible, and both favoured the full version of the tool. Study 2 investigated the effect of the support tool among a student sample in comparison to the paper-based training. Participants followed the training individually. Comparisons between the two groups revealed no significant differences on multiple outcome measures. Behaviour observed during the training suggests that shorter sessions might prove more effective. The findings indicate acceptance of the technology supported training but gives no indication that the effects of the training are improved by technological support.

scholarly journals A Dynamic Traffic Assignment Model for the Sustainability of Pavement Performance

2018 ◽  
Vol 11 (1) ◽  
pp. 170 ◽  
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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