ESTIMATION MODEL OF FLYOVER CONSTRUCTION PRICE (CASE STUDY IN DKI JAKARTA)
The flyover construction price estimation model was developed to expedite the price determination and reduce the disparity between budget submission and contract value. Procedures include categorizing beam types into five categories and adding five independent variables (variablex) that account for up to 83.33 percent of the total variance. These variables include maximum span length, clearance, deepest foundation depth, work area, and traffic. In addition, the contract value on the dependent variable is amended
to the reference year based on inflation statistics using 40 contract data for flyover building operations from 1992 to 2019 and adjusting for inflation. The study uses the most recent contract data to generate two models using multiple linear regression equations until the validity and model validation processes are accomplished. The first is a model for overpass construction: y
(cost)=34572.895+1.994x1 (area)-12140,138x7 (beam type), with a coefficient of determination of 91.72 percent and a cost difference varying from 14.4 percent to-23.2 percent. The second model is for flyover construction, with y (cost)=-15989,788+2.162x1 (area)+8326.753x8 (kind of foundation), a coefficient of determination of 81.96 percent, and a cost variance ranging from-17.27
percent to-16.5 percent.