Experimental Study on the Performance of Bond-Breaking Layer in Reducing Friction and Improving Anti-Erosion

Abstract

This research explored the variation of bond-breaking effect with variety of bond-breaking layers installed between the concrete pavement surface slabs and the lean concrete (LCB) base, in order to offer parameters for structure analysis of pavements with bond-breaking layers and to optimize the selection of bond-breaking layers for the practical road engineering projects. This research tested the bonding stresses and the frictional forces at slab-base interface of pavements under different bond-breaking condition, as well as the anti-erosion performance of base course, via the anti-erosion tests in laboratory and the field tests for mechanical performance of slab-base interface treated with different bond-breaking layers in some highway projects of Hunan and Guangdong Provinces. Bond-breaking media applied in this research include the 3cm asphalt concrete (AC), 1cm emulsified asphalt slurry seal (EASS), geotextile and emulsion wax curing agent (EWCA). The findings from the field tests for bonding stress between slab-base layers indicated that EASS and EWCA did better than geotextile in reducing friction or bonding stress between slab-base layers. And the findings from the anti-erosion tests indicated that: under the same conditions, specimens covered with geotextile did far better than specimens brushed with asphalt on the surface in resisting erosion, and specimens covered with geotextile or brushed with asphalt did far better than no bond-breaking layer in resisting erosion. The mechanical performance of slab-base interface with different bond-breaking media derived from this research offers scientific reference to pavement design and construction control in the practical road engineering projects. Key words: Mechanical performance of slab-base interface; Tests for bonding stress and anti-erosion tests; Bond-breaking layer of cement concrete pavement; Lean concrete base;Cement stabilized macadam base course.