Case Studies of Constructability Improvement in Public Transportation Projects

Constructability is critical to the success of public transportation projects, impacting cost, schedule, safety, and disruptions to the traveling public. This study examined eight constructability improvements on three recent public highway projects in California. Case study information was collected through review of project records and interviews with project participants. The study describes the constructability improvements and the resulting project benefits. The improvements were identified after project award, either before or during construction. The improvements were classified under five categories: (1) taking advantage of existing utilities, (2) traffic control improvements, (3) earthwork activities, (4) drainage system design, and (5) pavement design. Some improvements were developed as opportunities to eliminate or simplify some scope of the work, while others were developed during efforts to mitigate project-specific challenges. Several of the improvements were based on previous experiences of the CM and/or the contractors. The lessons learned from these case studies will be beneficial for design and construction of future highway projects.