Value Engineering for Roadway Expansion Project over Deep Thick Soft Soils

Abstract

A roadway expansion that takes place on soft ground is susceptible to differential settlement because of the high consolidation of soft soils. Therefore, steps must be taken to lessen the risk of such settlement; yet, this often only results in costly drainage solutions. In that, applying a systematic value engineering (VE) process can be beneficial to develop cost-effective design alternatives. However, VE studies specifically targeting for this problem are absent from the field. Thus, the goal of this study is to supplement this knowledge gap by applying a systematic VE process to an expansion project on soft ground to demonstrate the benefits of performing VE. A case study was performed on an expansion project over a soft soil layer approximately 50 m thick. Through the VE process, the original design was reviewed, problems were discussed, and three alternatives were proposed. Then value analysis techniques were applied to evaluate these alternatives in terms of cost saving, function improvement, and value improvement with respect to the original design. The VE process and design alternatives as applied in this study are expected to serve as a guideline for engineers and decision-makers in roadway expansion projects on soft ground.