Comparison of the top-down construction method and the bottom-up construction method in terms of cost and project duration

In this study, it is aimed to investigate the time and cost differences that will occur if structures built with top-down construction technology are built with classical techniques. The costs and project durations that will arise if underground structures with different depths and areas are constructed using the top-down construction method and the bottom-up construction method have been calculated and compared depending on the depth. Comparison graphs have been created. As a result of the values obtained, it has been seen that the bottom-up construction method is the most cost-effective choice at a depth of 8 m, while the top-down construction method becomes advantageous in terms of cost as the depth increases. The change in the building floor area of the structure did not have much effect on the percentage difference between the two methods in terms of cost. In the 10 models made with the top-down construction method, the project duration was advantageous compared to other systems. Similar to the cost results, the growth of the building floor area in terms of project duration did not affect the percentage difference.