A Cost Saving Strategy for Minimizing Pavement Restoration Costs

摘要

The cost of installing and maintaining underground utilities continues to increase. Pavement restoration costs can be reduced by as much as 80% by employing new and safer construction techniques such as the keyhole coring and reinstatement process developed and field proven over 20 years in the gas industry. We all know that trenchless technology has the potential to save millions of dollars when used for gas or water-pipe renewal, but the cost of restoring hundreds of excavations needed to reconnect service laterals robs those trenchless processes of much of their economies. Reconnection of service laterals is the most costly aspect of the job because they are the most numerous. On a typical residential street conventional pavement restoration costs can add $40-50 per foot to the overall cost of the rehabilitation project. That's $250,000 per mile of main. Employing keyhole coring and reinstatement methods to find and reconnect the service lateral avoids most of this restoration cost and the scarring of the streetscape. Keyhole technology can also be effectively used to locate underground facilities for preengineering activities or avoid potential underground conflicts when directional drilling. Other applications include locating and mapping underground infrastructure, deploying internal inspection cameras in buried pipes, installing equipment to evaluate integrity of buried pipelines from the outside using Broadband Electromagnetic (BEM) inspection, and cost effectively removing valves or other obstructions in abandoned gas or water mains to reuse that abandoned infrastructure as a conduit for new fiber-optic cable under congested streets. Like microsurgery in the medical field, the keyhole technology process enables utility crews to safely and cost-effectively conduct main replacement activities, locate underground infrastructure, and perform repair or maintenance work from the road surface through 18" or 24" diameter 'keyholes' cored through the pavement, thereby avoiding more costly, disruptive and inherently more dangerous excavation methods. The reinstated pavement cores result in a permanent, almost invisible, perfectly matching, waterproof pavement repair that can maintain the performance life of asphalt and concrete pavements and significantly reduce traffic delays and inconvenience to the public. Keyholes are smaller and less destructive to the pavement. They will not sink, allow infiltration of groundwater, or become future potholes. The reinstated core will support a wheel load of 50,000 lbs in just 30 minutes, as documented in testing performed by the University of Illinois. It is a reliable, field-proven process with more than 20 years of use and over 250,000 successful core reinstatements. In addition to reducing cost and public inconvenience, keyhole technology is also an environmentally friendly process that eliminates the need for new paving materials and the disposal of old, by reusing the same materials that were originally used to build the roadway to restore it after the excavation. The coring and reinstatement process reduces the carbon footprint of utility cuts and pavement restorations to one-twelfth of that generated by conventional means and avoids the consumption of millions of tons of asphalt paving materials and the disposal of millions of cubic feet of asphalt spoil every year in utility cut repairs.