Examination of the effects of the highway project elements on investment cost

Transportation is an important section of our life. This reason, the highway, which based of transportation, is very important. Recently, new projects that taken consideration vehicle numbers are prepared and applied. However, while opportunity of investment is limited, the economic projects are preferred. The economic projects are determined especially depending on preliminary construction cost. The most important parameter of construction cost is elements of project. For this reason in this study, while the construction of highway economically, the effects of project elements are researched. Because of this, firstly, horizontal and vertical alignment of highway must be determined. For highway investment cost, firstly, numbers of horizontal and vertical curves have been examinated, because, the horizontal and vertical alignments of highway which consist of horizontal and vertical curves. How affect the numbers of horizontal and vertical curves to highway investment cost that are researched. From this research, optimum numbers of horizontal and vertical curves are determined for first, second and third class of highways. As depending on, highway class and geometric standards, minimum elements of project are determined. The minimum elements of project are increased with definite rate up to maximum value of elements of projects. To determine for every class highway, how cost of investment are affected from variation. Therefore, for every class highway, optimum elements of project are determined and then the effects of element on investment cost are determinated and described with mathematical models. In addition, the effects of width of platform, which consist of width of shoulder and lane and width of nationalization, are examinated on investment cost of highway. Key words: Highways, investment cost, optimization, geometric models, regression.