The Effect Analysis of Traffic Volume, Velocity and Density in Dr.Siwabessy Salobar Road

Traffic density has been considered to be affected by the traffic volume and the traffic velocity. This study focuses on investigating the roles of both aspects on the traffic density along the street of Dr. Siwabessy, from Ambon City to Air Salobar or vice versa. This street has been considered to be one busy street in Ambon City with various vehicles passing by along with the crowded pedestrian activities and with new business centrals (e.g. school) along the road describing the complexity of the street traffics. From the study, it was found that the traffic velocity was statisitically the more significant factor in determining the traffic density compared to the traffic volume following the use of the coefficient regression model. The other finding is that the traffic along the street can be classified to be under-saturated


INTRODUCTION
According to Mashuri (2012) more and more community activity affect the characteristics of traffic flow like speed, volume and traffic density. According to Ekawati et al (2014), one of the main causes of traffic jam is unbalanced road capacity with an increasing number of vehicles. Dr. Siwabessy street in Air Salobar is one of the important streets in Ambon City, which serves the traffic flow from Ambon to Air Salobar. This road is used as a connecting lane from Ambon to Nusaniwe Sub-district. In recent years population growth in Nusaniwe sub-district has been caused the significant increase of vehicles through Dr. Siwabessy street. On the other hand, traffic jam caused by the activity from several new office and school building at this area. So Dr. Siwabessy highway segment will be more crowded because of the volume of vehicles and will affect to the capacity of existing highway. By looking at these conditions it is necessary to do a study to determine the speed, volume and density of roads Dr. Siwabessy-Air Salobar which is a highway that always passes many types of vehicles, as well as daily activities of society. So we will know the road capacity feasibility.

II. LITERATURE 2.1 Highway Definition
Highway are transport infrastructures covering all parts of the road, including auxiliary buildings and equipment intended for traffic. The other hand it means a place passed by vehicle that through a road so that the highway is a very important in all aspects of life. The highway is also affect of an economy and the progress of a country.

Capasity
The capacity of the highway is the maximum number of vehicles that can pass through the road within a period of one hour without causing traffic jam (Warpani, 1985). According to MKJI (1997)

Traffic Volume
The parameter used to determine daily traffic patterns is an average traffic (LHR), LHR obtained by traffic monitoring for 24 hours, in a few days and the result is averaged, expressed in vehicle / day or day / day can be calculated by the formula: Q : volume N : number of vehicle T : observation time

Velocity
Speed is the ratio between distance and time. The formula for calculating speed that is: with: V : velocity (km/hour) S : distance (km) T : time(hour)

Density
Traffic density is the number of vehicles that exceed the capacity of the highway. Density can be calculated based on speed and volume. The relationship between volume, speed, and density is as follows: Us Q D  with : D : Traffic density (vehicle/hour) Q : Traffic volume (vehicle/km) Us : mean traffic velocity of space (km/hour)

Saturation ratio
Saturation ratio defined as the ratio of traffic flow Q (smp / hour) to capacity C (smp / hour) is used as the main factor in determining the level of road segment performance.aturation is defined as the following formula; DS = Q/C with : Q : traffic flow C : capacity

Relation between Volume, Speed, and Traffic Density
The mathematical relationship between speed, volume, and density can be expressed by the following equation: Q : volume (SMP/hour) D : density(vehicle/km) S : speed (km/hour)

Passenger Car Unit
The passenger car unit abbreviated as SMP (indonesian factor) is the unit of vehicle in the traffic flow which is equivalent to the light vehicle / passenger car, using the passenger car's equivalence or multiplier factor of the vehicle type into one unit of SMP, where the SMP is influenced by the type / type vehicles, vehicle dimensions, and motion capabilities. The quantities of passenger car units vary according to the Indonesia Road Capacity Manual 1997 shown as follows: Preliminary studies -Preliminary study is the process of collecting data to support this writing -Library Studies Conducted by collecting references related to the support of writing, which is a theoretical study.
-Data Compilation Data compilation, is basically a process of collecting, processing and reporting data to get the final result of data half-baked ready to be processed at the stage of data analysis.
-Data Processing and Analysis. Data processing is an activity for converting raw data that has been obtained into a standard format approached by theoretical studies.

Traffic Volume Analysis
The number of motor vehicles operating on Dr.Siwabessy road is obtained based on survey during peak hours, in the morning, afternoon and evening, are presented in Table  4.1. Based on survey results of traffic volume on road Dr. Siwabessy can be seen that the maximum vehicle volume is at 08.00-09.00 with the direction of Ambon -Air Salobar of 1909 vehicles / hour and at 07.00-08.00 with the direction of Air Salobar -Ambon of 1283 vehicles / hour. Subsequently converted into units of passenger cars (smp) using the Highway Manual Capacity Indonesia 1997 for each road segment. Based on the table 4.5. can be seen for Dr.Siwabessy road segment ratio has less than 1, this indicates that the condition of traffic flow is still below saturated From the above table it is known that in the direction of Ambon to Air Salobar vehicle speed is slower than the direction of Air Salobar to Ambon, this is because vehicles entering Air Salobar area are more dense than vehicles from Ambon to Air Salobar.   /dx.doi.org/10.22161/ijaers.4.11.17  ISSN: 2349-6495(P) | 2456-1908(O) www.ijaers.com  (Ambon to Air Salobar) The following relationship between volume (Q), speed (Us) and vehicle density (D) by using regression analysis on Dr.Siwabessy road direction Ambon to Air Salobar. By using regression data processing using Excel function, it is known that the regression equation, D = 18,32 -0,435 [Us] + 0.024 [Q] gives prediction of vehicle density with very high correlation value (R2 = 0.999) to calculation of vehicle density by using formula 2.8 (see Figure 4.1). Furthermore, based on the value of regression model equations, the effect of vehicle speed on the road direction from Ambon to Air Salobar is more dominant.

Air Salobar-Ambon
Relation between volume (Q), speed (Us) and vehicle density (D) by using regression analysis on Dr. Siwabessy road from Air Salobar to Ambon. By using regression data processing using Excel function, it is known that the regression equation, D = 18,67 -0,396 [Us] + 0.021 [Q] gives prediction of vehicle density with very high correlation value (R2 = 0.999) to calculation of vehicle density by using formula 2.8 (see Figure 4.2). Furthermore, based on the value of regression model equations, the effect of vehicle speed on the road direction from Ambon to Air Salobar is more dominant than the road volume where the regression coefficient of vehicle speed is 0.396 is greater than the regression coefficient of the volume which is 0,021.