The Texas Department of Transportation (TxDOT) uses sprayed seals to resurface existing pavements (seal coats) and as a wearing course for new roads (surface treatments). Seal coats are the dominant application and are the central component of TxDOT's preventive maintenance program for lower-volume roads. TxDOT also widely uses spot seals and strip seals as a routine maintenance measure. Since FY01, TxDOT has contracted or performed an average of 109 million square meters of seal coat maintenance annually at an average cost of $198 million (US Dollars). In support of this investment, TxDOT has strategically sponsored research directed at improving seal coat and surface treatment quality and cost effectiveness. Most elements of the sprayed seal process, ranging from macro-level application issues to micro-level material issues, have been explored during the past 10 years. Research topics include surface treatment and seal coat design, specifications, constructability, testing and inspection, binder-aggregate compatibility, binder quality assurance, and maintenance considerations. but the method presented here has been checked against what has actually been successful on a large number of sites. (a) For the covering entry of this conference, please see ITRD abstract no. E217100.
Samenvatting