Patching is one of the most common maintenance methods for potholes in roads. In order to improve the performance of cold-patching asphalt mixtures, an emulsified asphalt modified with waterborne epoxy resin was developed. Two waterborne epoxy resins and two curing agents were selected. The optimal experimental contents of the curing agents were obtained by measuring the compressive strength of the waterborne epoxy mortar (WEM) under different curing agent contents and curing period. The difference between the two waterborne epoxy resins was obtained by the flexural strength and stress–strain curves, which were measured by the modified bending test on the WEM. The evaluation method of the initial strength and forming strength of the waterborne epoxy emulsified asphalt mixture (WEEAM) was proposed by the experimental study of the compaction molding method and curing conditions. The high temperature performance, low temperature performance, and moisture susceptibility of the mixture were verified by comparing various kinds of WEEAM. The results show that using WEEAM as a road repair material has great advantages in improving pavement performance and road service levels.

This investigation was carried out to study the effects of the type and amount of supplementary cementitious materials on mechanical properties and surface durability of Portland cement concrete (PCC) pavement. Three supplementary cementitious materials, two types of fly ash and one ground granulated blast furnace slag, were selected to substitute for a portion of Portland cement with three level contents (5, 15, 25 wt% and 15, 25, 35 wt% for single and compound adding, respectively) in the concrete mixtures. Properties of the concrete were evaluated in laboratory including compressive strength, flexural strength, surface abrasion resistance, surface frost resistance,and microstructure analysis. The results show that the early age strength values of concretes were affected as increasing the replacement contents regardless of fly ash and slag. Effects of both the type and dosage of supplementary cementitious materials on surface abrasion resistance and frost resistance of concrete were remarkable. The concrete with slag had poorer wear resistance than reference concrete and those with fly ash. In addition, general fly ash concrete had worse surface frost resistance than other mixtures, and concrete with slag exhibited better surface frost resistance in saturated sodium chloride solution than reference one and fly ash concrete.

Recently, there has been an increasing interest in the applications of recycled mixtures with a high reclaimed asphalt pavement (RAP) content. However, many government departments are hesitant about the applications of that due to being worried about the durability of its pavement, and few findings has been reported in terms of the percentage of fine reclaimed asphalt pavement (FRAP, 0~5 mm) in recycled mixtures. In this paper, 25% or more RAP by the weight of aggregates is defined as high RAP and high FRAP refers to 10% or more FRAP by the weight of aggregates. This paper examines the laboratory performances of mixtures with high RAP (30%, 40%, and 50%) and FRAP (10%, 15%, and 20%). Performance evaluations have been conducted by conventional tests, including the low-temperature bending test, fatigue test, and the moisture susceptibility test. The results show that with the increasing RAP and FARP contents, 41% (30-R-10) to 63% (50-R-15) of virgin asphalt can be saved, both the low-temperature and fatigue performance decrease, and the moisture performance firstly increases and then decreases. The results of analysis of variance (ANOVA) in terms of low-temperature and moisture performance show that RAP contents in recycled mixtures have a significant effect on the performance, while the effect of FRAP contents on the performance of recycled mixtures is insignificant.