Development of Work Activity Matrix for Microtunnel Quality Assurance, Inspection, and Risk Management during Construction

摘要

Initial microtunnel inspection reports were in the form of daily journals consisting of descriptive sentences and paragraphs with recurring but updated project-mandated information such as date, weather, temperature, equipment, and crew size. The daily journal presented a narrative of work activities performed to advance the microtunnel boring machine (MTBM) including length of tunnel excavated, number of pipes installed, observation of excavated soil material discharge at the soil separation plant, estimated units installed for schedule of values computation for monthly pay estimates, and actualized work completed for monthly construction schedule update. Except for numerical data input, daily microtunnel reports were lengthy with varying writing styles.The introduction of desktop computers in the early 1990s alleviated many of the challenges associated with handwritten reports. The inspection record keeping for microtunneling construction projects has evolved into a quality management and risk management tool based on lessons learned and the need for tracking additional parameters.This paper presents the development of a microtunnel inspection management plan for documenting quality assurance, tracking progress, resolving challenges, and following up on nonconforming work to ensure the project is completed in accordance with the contract documents. The focus herein is on the evolution of this microtunnel inspection management plan, reporting processes, and procedures into a standardized reporting template to capture relevant project data. This template serves as a training module for developing a work activity matrix (WAM) for microtunneling inspection and risk management applicable to small, medium, and large-diameter pipeline installation in different ground conditions.