Use of Acoustic Inspection for Prioritizing Renewal and Replacement Projects at Ft. Jackson, South Carolina

摘要

Current useful life estimation techniques rely heavily on professional judgment based on a wide range of available information including asset age, physical condition, maintenance history, prior operational issues, and other data. Inspection of collection system assets is often limited to visual inspection of the manhole and not direct inspection of the pipe with technology such as CCTV. Even though direct inspection with CCTV would significantly enhance the useful life estimation, the scope and cost associated with collecting these data for each pipe segment within a collection system can be difficult to justify. InfoSense, Inc. has developed the Sewer Line Rapid Assessment Tool (SL-RAT) to provide utility operators with a new capability to inspect pipe segments. The SL-RAT was designed specifically to act as a cost effective tool for prioritizing maintenance operations based on rapidly assessing the degree of blockage within sewer line pipe segments. It has proven an effective tool in prioritizing cleaning operations. The objective of this study is to evaluate the cost effectiveness of using the SL-RAT to enhance asset useful life estimations and the subsequent use of that information to prioritize R&R projects. An inspection of 2,600m (8,500ft) of 45.7cm (18-inch) and 61cm (24-inch) pipe was performed using CCTV at Ft Jackson, near Columbia South Carolina. The CCTV inspection campaign took 45 hours. This run of pipe was also inspected acoustically using the SL-RAT device. The SLRAT inspection was performed in under 5 hours using a two person crew. Overall the SL-RAT proved to be effective in identifying major issues, but it was found that using the device on larger diameter pipes required a more conservative scoring approach when evaluating acoustic scores.