Technical and economic assessment for choosing of bridge structures waterproofing under cast hot asphalt concrete

Abstract

The existing technical level analysis of the polymeric materials requirements determination for waterproofing of the bridge structure carriageway slab is carried out. Nowadays new durable sprayed materials based on isocyanate: polyurea, polyurethanes, polycarbonates find mass application in transport construction. The waterproofing layer is applied on the priming layer by hot spraying method using special equipment, with the formation of a strong, elastic, seamless, waterproof coating, which when applied reproduces the shape of the geometry of the insulated surface. To ensure the service life, recommendations for improving the bridge structures sprayed polymer waterproofing technology at low temperatures are developed. The technological solution providing the directed thermophysical regulation of bridge structures roadway slab sprayed polymer waterproofing based on the isocyanates at low temperatures on the basis of prevention and elimination defects (caverns) point is presented. The technical and economic calculation confirming the sprayed waterproofing technology application efficiency in comparison with traditionally used roll materials have been carried out. Due to the new technology application, the number of current repairs is reduced from 24 to eight for a range of 49 years. By calculation means using the programme developed by the author, the discounted payback period for the sprayed polymer waterproofing technology was established at the beginning of the 17th year.