Under contract to the Dutch Department of Public Works Civil Engineering Division, SWOV Institute for Road Safety Research carried out simulation studies on the development of H4-level safety barriers. These included steel and concrete designs for a wide STEP barrier. Anchoring of these constructions in concrete was always the starting point for research simulations. The steel STEP barrier also had to be capable of being used with asphalt. However, there was no useful information available about anchoring in asphalt. This was therefore the basis for this research involving a number of loading tests. Three types of anchor bolts were tested. Two of these, the so-called "VD" anchor and the "VD-I" anchor, were adhesive anchors. The third anchor, the so-called "Schweizer Riegel" (SR) anchor, was a mechanical one. The anchors consisted of M24 studs with an 8.8 quality rating. The placement depth was varied with the "VD" anchors, and a range of speeds and forces was tested with the "SR" anchors and the "VD-I" anchors. The most important conclusion from this research was that "SR" anchoring is a good option for anchoring in asphalt at H4 level. The research simulations for the STEP barrier involved four anchors, each with four anchor bolts, that together could absorb 1600 kN of tensile force. Four "SR" anchors, with four bolts per anchor, were more than sufficient to absorb this force (maximum force 2768 kN). "VD" and "VD-I" anchors with the same configuration were unable to absorb sufficient force. (A)
Samenvatting