Finding a Balanced Contracting Approach to Pre‑Excavation Grouting

摘要

Tunneling often requires pre-excavation grouting to reduce groundwater inflows and improvernground conditions. However, the work is expensive, the amount of grouting is a function of the contractor’srnmeans and methods, and its overall efficiency is debatable. Over the years, the industry has struggled withrndifferent payment mechanisms to administer this work, but typically few seem to assure the contractor ofrngetting through the ground while also allowing the owner to control cost and schedule overruns. This paperrnexamines a payment mechanism and contractual considerations used on the SFPUC’s New Irvington Tunnelrnthat may help meet these goals of cost and schedule control.