By conducting a series of plane strain experiments on samples of a soil reinforced with new horizontal–vertical (H–V) reinforcing elements. The influences of minor principal stress, configurations of horizontal and H–V inclusions, and the height of vertical element on the behaviour of the soil are presented and discussed. The experimental results showed that the strength of the soil reinforced with H–V inclusions is higher than that of the sandy soil with horizontal inclusions. The strength of the soil reinforced with H–V inclusions rises with increasing height of the vertical elements, reinforcing ratio of the inclusions and the minor principal stress. Based on limit equilibrium theory, a strength model was developed for the soil reinforced with H–V inclusions under plane strain conditions. The predictions from the strength model are in good agreement with the experimental results.

This study investigated the positive effect of the combined use of recycled asphalt shingles (RASs) and municipal solid waste incineration (MSWI) bottom ash (B.A.) in asphalt concrete, which contributes to enhanced sustainability in pavement engineering. In addition, unlike traditional approaches that employ individual recycling material in hot mix asphalt (HMA), the combined use of the two waste materials maximizes the mechanical performance of the asphalt mixture. The addition of RAS (with 30–40% aged binder) as an additive generally enhances the strength/stiffness of the asphalt mixture. The high porosity/absorption of MSWI BA results in an additional amount of liquid asphalt binder in the mixture. As an admixture, RAS could supply the additional asphalt binder in the mixture when MSWI BA is used as an aggregate replacement. This research was conducted in two phases: (1) to examine the effect of MSWI BA alone and its optimal asphalt content (OAC), and (2) to assess the combined effect of B.A. and RAS in HMA. Multiple laboratory testing methods were employed for the mechanical performance investigation, including the Marshall stability test, rutting test, and indirect tensile test. The testing results show that the 20% B.A. replacement exhibits the best performance and that it requires an additional asphalt binder of 1.1%. For the combined use of MSWI BA and RAS, 5% RAS shows the best mechanical performance. All mixtures that contain the B.A. and RAS show greater strength than the control specimen (regular HMA).