Reducing the Intrusion: Instrumentation and Monitoring for Urban Excavation with Non-Contact Technologies

ABSTRACT: The Instrumentation and Monitoring Program (IMP) is becoming a critical aspect of project scope due to the increasing complexity and sensitivity of the environment surrounding deep urban excavations. The items monitored include the ground, shoring structures, adjacent buildings, roads surfaces as well as underground utilities. However, there are also constraints on the deployment of an IMP such as the congestion of the construction sites, the difficult access to the instruments, the (lack of) coordination among multiple players, the myriad of permits and clearances required, the continuous traffic of vehicles and of pedestrians, etc. It is very common that the implementation of the IMP gets delayed, that its scope gets reduced, or that the continuity of the monitoring data is jeopardized, increasing the overall geotechnical and structural risk associated to the project. This paper introduces state-of-the art IMP technologies. Focus will be on the advantages and limitations of those technologies by demonstrating how they can individually be beneficial for the success of the project (safety, reliability, productivity, competitiveness, etc..).