Research Article Reliable Laboratory Tests: A Prerequisite for the Design of High-Quality Slurry Surfacing Mixtures Alexandra Destr´ ee , Stefan Vansteenkiste , Tine Tanghe , and Jo¨ elle De Visscher Belgian Road Research Centre (BRRC), Brussels, Belgium Correspondence should be addressed to Alexandra Destr´ ee; a.destree@brrc.be Received 2 December 2021; Accepted 18 February 2022; Published 22 April 2022 Academic Editor: Andrea Grilli Copyright © 2022 Alexandra Destr´ ee et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Surface treatment with slurry surfacing is a quick and cost-effective technique to restore the condition and performance of a road surface, compared with the replacement of the wearing course. It is therefore not surprising that cities and municipalities, faced with increasingly tight budgets, choose slurry surfacing to maintain their roads. A slurry surfacing with good performance and a long service life requires, above all, a well formulated mixture and a good control of the execution quality. Slurry surfacing could then even be considered for ultrathin wearing courses on new pavements. From 2016 to 2020, the Belgian Road Research Centre (BRRC) was engaged in a 4-year research project called BeP2S (Better Performing Slurry Surfacing) financially supported by the Belgian Bureau for Standardization (NBN). e project focussed on laboratory testing, gathering data and field experience, assessing the link between laboratory and field performance, and the mix design process. is paper is dedicated to the European test methods of the EN 12274 series (“Slurry surfacing–Test methods”), as well as some alternative test methods, which were evaluated (complexity, relevance for the mix design process, ...) and improved in terms of test conditions, precision, and discriminating power. Five performance-related tests proved to have sufficient ability to discriminate between mixtures with variations in mix design. Recommendations were made for the ranges within which the laboratory test results should fall in order for the slurry surfacing to perform well. 1. Introduction and Background Slurry surfacing techniques are used to maintain and extend the service life of existing pavements through restoring char- acteristics such as skid resistance and imperviousness, using little resources and with less traffic disruption. Slurry surfacing includes slurry sealing and microsurfacing [1–4]. Slurry is a cold mixture consisting of a well-graded mineral aggregate blend, emulsion (which may be modified with polymer), water, and, where appropriate, additives (cement, breaking retardant, etc.). Slurry surfacing is proportioned, mixed, and uniformly laid on-site at ambient temperature, using mobile machinery. e mix is evenly spread in one or two layers, with thicknesses slightly greater than the maximum aggregate size. e slurry surfacing shall be applied over a properly prepared surface to guarantee adequate long-term performance (resistance to abrasion, ravelling, bleeding, etc.) [5–8]. Slurry surfacing offers a wide range of economic and technical advantages, as well as social and environmental ones, when compared to repaving the wearing course with hot mix asphalt [9]: (i) less material and energy consumption during construction (with respect to hot mix asphalt); (ii) lower fuel consumption in the use stage (less greenhouse gas emissions), thanks to lower rolling resistance; (iii) road safety and comfort maintained constant at a high level; (iv) less traffic disruption by road works (usually faster application times than alternative conventional approaches); (v) better and safer working conditions for road workers (particularly on very hot summer days), etc. Since this technology requires less material resources, is cold produced, and laid at low thickness, the direct cost price is low. Hindawi Advances in Materials Science and Engineering Volume 2022, Article ID 7157233, 20 pages https://doi.org/10.1155/2022/7157233