Application of computer simulation software (NETSIM) for the improvement of a signalized intersection in Bangkok | |
| Author | Ahad, Memon Abdul |
| Call Number | AIT RSPR no. TE-97-05 |
| Subject(s) | Roads--Thailand--Bangkok--Interchanges and intersections Traffic engineering--Simulation methods |
| Note | A research submitted in partial fulfillment of the requirements for the degree of the Master of Engineering, School of Civil Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | The aim of this study was to propose the optimal signal settings of a selected intersection, Huai Khwang Intersection in Bangkok, through the application of NETSIM (NETwork traffic flow micro SIMulation model). In order to achieve the desired objectives, initially the existing signal settings of this intersection were examined and then a suitable cycle time was proposed. For further improvement of this intersection, some changes in its geometric configuration were also recommended. The ex1stmg condition of the intersection and the proposed alternatives were simulated through NETS IM. After analyzing the existing condition, it was concluded that the occurrence of delay is due to the improper operation of signal settings, inadequate inflow lanes and incorrect provision of lane markings. Under the existing condition, the shortest observed cycle time was 96 seconds and the longest cycle time was 155 seconds, while the corresponding delays were 76.4 sec/vehicle and 72.2 sec/vehicle, respectively. To improve the efficiency of this intersection without any alteration, a more suitable cycle length of 137 seconds was proposed and this would yield a reduction of 16.83% in delay. The further improvements were achieved by proposing different alternatives, which were simulated and analyzed with respect to minimizing delays. By changing the lane markings of the approaching roads, a reduction in delay of 4.53% could be achieved. Shifting bus stops 500 meters away from the intersection and providing a parking bay would reduce the delay by 7 .21 %. Different phasing patterns and cycle lengths were also proposed. The new proposed four phases pattern together with the most suitable cycle length of 117 seconds were recommended and this alternative would reduce the delays by 22. 71 %. Furthermore, the combination of this proposed best cycle time, phasing pattern and changed lane markings would give a reduction of28.21 % in delay. To provide adequate inflow lanes on the west, traffic lanes were rearranged by converting an outflow lane on the west approach to be an inflow lane. Under this new arrangement of traffic lanes, a cycle time of 99 seconds was proposed. This alternative would reduce the delay by 50.68%. To eliminate the bottleneck problem, it was proposed to construct an additional lane on east-west approach. This proposal would bring a reduction of 55.35% in delay. Bearing in mind the ease of implementation and cost effectiveness of each proposed alternative, it was finally recommended that an inflow lane on the west approach shall be added by rearranging an out flow lane to become an inflow lane. This proposition would reduce the average delay per stopped vehicle by more than 50 %. |
| Year | 1998 |
| Type | Research Study Project Report (RSPR) |
| School | School of Civil Engineering |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Transportation Engineering (TE) |
| Chairperson(s) | Yordphol Tanaboriboon; |
| Examination Committee(s) | Nakatsuji, Takashi ;Chotchai Charoenngam; |
| Scholarship Donor(s) | Government of Japan; |
| Degree | Research Studies Project Report (M. Eng.) - Asian Institute of Technology, 1998 |