Online ISSN : 1880-6465
Print ISSN : 0287-6256
ISSN-L : 0287-6256

ジャーナル フリー

1991 年 22 巻 1 号 p. 293-311

In this paper we will attempt to measure the economic benefits of a large-scale forestry road improvement project. The economic benefits to which we will pay attention here are those measurable ones in montary terms. They concern the reduction in traveling costs and time saving of vehicles that will use this large-scale forestry road.
At first we will measure the reduction in vehicle traveling costs, using the following formula:
BCtj=(TCto-TCtj),
where,
BCtj=reduced vehicle traveling costs at each year (t) after road improvement (j). TCto=traveling costs of vehicle at each year (t) before road improvement (o).
TCtj=traveling costs of vehicle at each year (t) after road improvement (j). The calculating procedures are based on the following: (1) Classfication of the kind of vehicle.
(2) Estimation of average daily traffic by vehicle at each section.
(3) Calculation of average speed of vehicles before road improvement.
(4) Computaion of traveling costs by vehicle at each section.
(5) Calculation of the reduction in vehicle traveling costs at each section.
(6) Estimation of the benefits by saving of vehicle traveling cost at all sections.
Next, we will measure the benefits by time saving of vehicles. The measuring formula is:
BTtj=(TTto-TTtj),
where,
BTtj=the saving of vehicle traveling time at each year (t) after road improvement (j).
TTto=time cost of vehicle at each year (t) before road improvement (o).
TTtj=time cost of vehicle at each year (t) after road improvement(j).
We will calculate the benefits by time saving of vehicles based on the following procedures:
(1) Classfication of the kind of vehicle.
(2) Estimation of average daily traffic by vehicle at each section
(3) Calculation of the value of time by vehicle.
(4) Computaion of the reduction of time at each section.
(5) Calculation of the amount of time saving by vehicle at each section.
(6) Estimation of the benefits by time saving of vehicles at all sections.