STATIC PIPE BURSTING USING VITRIFIED CLAY JACKING PIPE IN PHOENIX SOILS

摘要

The City of Phoenix, Ariz., recently elected to perform two large pipe bursting projects; one of these projects utilized vitrified clay jacking pipe as the replacement pipe material. The notice to proceed for the project was given May 12, 2008. The Guaranteed Maximum Price (GMP) for the project is $5,323,524.05. This project represents a first in both (1) the most significant upsize and (2) maximum drive length in the United States using the static pull bursting method with replacement segmental pipe. This project also demonstrates a commendable level of cooperation between equipment manufacturer, product pipe manufacturer, contractor, engineering firm and municipality. One of the first sections replaced included bursting and replacing 1,200 m (3,938 ft) of existing 300 mm (12 inch) VCP with 450 mm (18 inch) VCP. The existing sewer line's capacity had been exceeded due to growth of the contributory service area. The utility corridor encompassing the existing line was congested with other utilities making open cut construction challenging. Trenchless pipe bursting was ultimately chosen because of the adjacent utilities and concern of traffic disruption. Soil conditions in the area proved to be one of the biggest challenges. The original pipe to be burst was bedded in a soft dry silty sand material and installed in a trench width ranging from 1 to 1.5 m (3 to 5 ft) depending on depth. Existing trench depths range from 3 to 6 m (10 to 20 ft) deep. This first segment was successfully completed on June 10, 2008.