Underground structures are subject to deterioration conditions in which water leakage occurs through cracks due to the long-term influence of soil and groundwater. Therefore, composite waterproofing sheets can play an important role in securing the leakage stability of structures by combining them with concrete structures. In this study, a total of eight composite waterproofing sheets were used according to the thickness of the compound and the properties of the material attached to the concrete, and the deformation characteristics at the bonding surface were identified through repeated tensile tests. Types A, B, and C, with a compound thickness of 1.35 to 1.85 mm and a single layer, had strong bonding performance, with a deformation rate of 0.5 to 2 x 10-4 and a DE/RE ratio of 0.3 to 1.3; tensile deformation progressed while maintaining integrity with the concrete at the bonding surface. Types D and E were viscoelastic and non-hardening compounds with a compound thickness of 1.35 to 3.5 mm, where the strain rate due to tensile deformation was the lowest, at 0.1 x 10-4 or less, and the DE/RE ratio was -5 to 3; therefore, when internal stress occurs, the high-viscosity compound absorbs it, and the material is judged to have low deformation characteristics. Types F, G, and H, which were 2 to 2.9 mm thick and had two layers using a core material, were found to have characteristics corresponding to tensile deformation, as the strain rate increased continuously from 0.2 to 0.5 x 10-4, and the DE/RE ratio increased up to 8 mm of tensile deformation.

The construction industry is increasingly focusing on sustainability, creating a need for innovative materials. This comprehensive review examines the potential of calcined clays and nanoclays in enhancing construction materials and promoting resilient infrastructure. It emphasises their role in improving performance and supporting environmental conservation in sustainable development. The review discusses how varying proportions of calcined clays and nanoclays impact the performance of pavement materials, especially when combined with bitumen in asphalt mixtures. It highlights their benefits, including reduced chloride penetration, enhanced water resistance, and improved soil conductivity. Overall, the review suggests that the strategic integration of calcined clays and nanoclays into construction materials can enhance durability, optimise resource use, and support environmental sustainability.

Solar radiation in plateau permafrost regions is strong. The asphalt pavement strongly absorbs and slowly dissipates heat, leading to significant heat accumulation on the pavement. This accumulation disturbs the underlying permafrost and eventually causes serious pavement damage. To improve the heat resistance and dissipation capabilities of asphalt pavement, a nanofluid directional heat conduction structure (N-DHCS) was suggested and analyzed in this paper. The designed structure can resist heat in the daytime due to the low thermal conductivity of liquid and dissipates heat at night through natural convection. The finite element method and laboratory irradiation experiment were employed to performed thermal analyses of N-DHCS. The results demonstrated that establishing the N-DHCS in asphalt pavements can enhance active heat dissipation capacity, which is beneficial for protecting the frozen soil in plateau permafrost regions.

Cement kiln dust (CKD) is the by-product of cement manufacturing. It is collected using air pollution control devices (APCDs) also known as electrostatic precipitators in the form of flue dust to minimize environmental hazards. This study investigates the potential use of CKD as a filler material and its novel antistripping properties on recycled asphalt pavement (RAP). CKD's chemical properties, make it desirable for improving stripping resistance of asphalt in areas prone to high rainfall or moisture exposure, but its application in RAP remains a grey area to explore. Its dual role in improving both adhesion and mechanical properties of asphalt makes it particularly advantageous, in terms of sustainability, cost and resource efficiency. The rising production cost, environmental safety concerns, and the push towards sustainable consumption/production seek alternatives for traditional antistripping agents for asphalt production, thus, CKD. This study prepared dense-graded asphalt concrete with nominal maximum aggregate size (NMAS) of 14 mm with 1%, 3%, and 5% of CKD by weight of RAP according to Malaysian standard. A total of five (5) asphalt concrete (AC14) mixtures were produced with an optimal 3% CKD used in the modified mixtures at the optimum binder content (OBC). The antistripping properties of CKD in hot mix asphalt (HMA) were assessed through indirect tensile strength test (ITS), indirect tensile stiffness modulus (ITSM) and boiling tests on the asphalt mixtures. In addition to the physical, mechanical, chemical, and structural/morphological tests, the safe inclusion of CKD in terms of heavy metals was evaluated by applying toxicity characteristic leaching procedure (TCLP) test. The findings confirm that CKD meets ASTM C150 standards for type II and type IIA hydraulic cement for use as a filler in asphalt. The fatigue cracking resistance, antistripping resistance in terms of the tensile strength ratio (TSR) & indirect tensile stiffness modulus (ITSM) tests indicated that CKD modified RAP mixes performed better than the control (CNTRL), RAP only and CKD modified RAP mixes. It also compares favourably with CNTRL + CKD mixture. Ultimately, the boiling test results indicated that CKD blended RAP mix surpassed the minimum 80% TSR for moisture damage resistance.

The durability of permeable pavement needs to be further studied by accelerated pavement testing (APT). Full-scale APT facilities are commonly associated with a very high initial investment and operational costs. A piece of small-scale accelerated testing equipment, the model mobile load simulator (MMLS), was used to investigate and evaluate the mechanical properties of three types of permeable asphalt pavements, including a 4 cm porous asphalt layer with cement-treated permeable base (4PA-CTPB), 7 cm porous asphalt layer with cement-treated permeable base (7PA-CTPB), and 7 cm porous asphalt layer with cement-treated base (7PA-CTB). Under different conditions of subgrade soil, transverse and longitudinal strains at the bottom of the porous asphalt layer and average rut depth and temperature data were collected. The results indicated that 4PA-CTPB produced the maximum average rut depth but minimum resilient tensile strain. The transverse resilient tensile strain of 7PA-CTPB was significantly higher than the other two structures under both wet and dry conditions. The transverse resilient tensile strain significantly increased with increasing loading cycles with a decreasing rate, which could be affected by both load and temperature. MMLS could be used to explore and evaluate the mechanical properties of permeable asphalt pavement. From the data under dry and wet conditions, it may be better to increase the strength of the subgrade, where a suitable hydraulic conductivity coefficient should be considered.

Hazardous alkylphenol wastes (HAPW) are a class of organic semisolid waste characterized by large production, complex composition and difficulties associated with recycling. Their generation and disposal lead to significantly environmental issues, including water and soil pollution, and present a substantial industrial challenge. To address these issues, a sustainable, low-carbon strategy for the high-value utilization of HAPW has been proposed. We take HAPW as a compatibilizer in the production of epoxy asphalt for road construction materials. Experimental results show that the HAPW-based epoxy asphalt containing 19.5 wt% HAPW exhibited optimal mechanical properties (tensile strength: 4.16 MPa; elongation at break: 164.92 %), exceeding industrial standards and outperforming epoxy asphalt produced using commercial cardanol through conventional processes. With a detailed molecular dynamics simulation, it is found that the HAPW plays two key roles in enhancing the interactions between epoxy resins and asphalt: (i) HAPW generates numerous hydrogen bonds with both asphalt and epoxy resin phases, strengthening noncovalent interactions and improving interfacial miscibility between the two phases. (ii) HAPW could react with the epoxy resin through the phenolic hydroxyl group, which further improves the interactions between epoxy resin and asphalt. This approach facilitates the treatment of hazardous organic waste in an environmentally sustainable and low-carbon way, enabling the recovery and repurposing of organic waste into high-valued products. Consequently, it promotes the resource utilization of industrial wastes while simultaneously contributing to a reduction in carbon emissions.

In recent years, owing to the advancement of highway infrastructure, modified asphalt has been extensively employed in pavement engineering. Asphalt mixture will invade the soil under high-temperature conditions, affecting soil cracking. Cracking characteristics caused by dryness of the mixed samples of modified asphalt and soil accounting for 0%, 2.5%, 5%, and 7.5% of the total weight were investigated in this paper. According to the water loss situation, the degree of cracking was determined. The crack development was quantitatively analyzed by digital image processing technology, so as to analyze the influence of modified asphalt on soil cracking under different contents. The results show that the soil was relatively better than the normal state. Under the same conditions, the moisture content of modified asphalt soil with 2.5%, 5%, and 7.5% increased by 30.17%, 63.49%, and 110.37% compared with that without modified asphalt. At the same time, due to its special bonding properties, it can effectively improve the cracking of soil. The cracking rate of modified asphalt soil with 2.5%, 5%, and 7.5% content is reduced by 11.58%, 20%, and 31.58%, respectively. The soil added with modified asphalt can effectively increase the total porosity of the soil, thus improving the ability of water absorption, and also can well inhibit the rate of soil evaporation and reduce cracking. Modified asphalt can be rationally applied not only to have soil mechanical properties improved but also to have waste asphalt utilized to reduce environmental pollution.

In modern highway construction, asphalt pavement is a widely used structural form, which is easily affected by various external conditions, among which the temperature effect is the most significant. In this paper, the cohesion model is used to simulate the structural cracks of asphalt pavement, the finite element method is used to simulate the asphalt concrete pavement model, and the temperature field simulation model of the pavement is established by using ABAQUS software, with the help of which the spatial distribution of stresses under different temperature conditions is deeply explored, and then the crack extension law during the process of temperature change is systematically investigated, and the effect of the temperature load on the degree of damage to the asphalt pavement is also studied. With the temperature change, the pavement surface layer is affected the most, and the soil base layer is affected the least. The higher the external temperature, the larger the crack expansion width inside the pavement structure, and the faster the corresponding expansion rate. The fatigue damage rate of the pavement structure is accelerated along with the increase of temperature. The research results can provide a theoretical basis for improving the high temperature performance of asphalt pavement.

Biochar provides a sustainable carbon sequestration technology, an effective fertilizer in agriculture, a step forward for the profitable and safe disposal of bio-wastes, reduced carbon dioxide emissions and global warming, and a renewable energy source. Using biochar as a bitumen modifier in asphalt pavement construction is under active research. It can prove a sustainable and environmentally friendly alternative, provided it meets the efficiency, strength, and economy challenge. This review focused on the available literature on utilizing biochar as a bitumen modifier for the construction of asphaltic roads. The studies show that biochar's physical and chemical nature has helped project it as a promising bitumen modifier. The biochar, being porous and fibrous, provides a strong, stiff frame in the asphaltic mast and results in the enhancement of both stiffening point and viscosity. This, in turn, leads to a reduction in penetration or increased deformation resistance. This is perhaps the reason for the high performance of biochar-modified asphalt at high temperatures. The increase in viscosity of asphaltic masts was also observed due to biochar amendment, making asphalt more sensitive to temperature. The two important factors, the complex modulus and the rutting factor of the asphalt, were noticed to increase with the addition of 10% biochar. The biochar amendments of up to 20% increased fatigue resistance temperature by 4.6 degrees C. The improvement in the resistance to deformation at high temperatures, probably due to a reduction of phase angle due to adding biochar, is also seen as a significant function of biochar. However, biochar applicability in the field is mainly related to its cost efficiency and performance as a bitumen modifier for asphaltic pavements. So far as the cost economy is concerned, the mean price for biochar (as per available literature) was very high, from $2.65 to $0.09/kg for blended biochar. The price was as high as $3.29/kg in the Philippines to $0.08/kg in India and in the US to $13.48/kg, implying that the market price of biochar is variable worldwide and dependent mainly on the biochar feedstock, cost of labor/living of the area and land costs. On the other hand, its efficiency has not yet been satisfactory at low temperatures. The other noticeable limitations that need to be explored in further research are long-term effects on strength, rutting resistance, and ageing. Also, field studies to support the research and, more importantly, cost economy viz-a-viz other available modifiers need exploration.

Increasingly, Climate Change (CC) is yielding more adverse climatic conditions that lead to the occurrence of natural hazards. Within these CC-related phenomena, it is possible to list global warming, flooding events, and urban heat islands. These scenarios generate damage to road infrastructure to a greater or lesser extent. Consequently, the CC-related phenomena affect the interconnection of production centers with cities and other communities. In this way, as CC causes potential damage to the pavement structures, socio-economic growth rates are correspondingly decreased. The preceding reveals the importance of designing CC-resilient asphalt pavements, which represent the vast percentage of transport infrastructure built worldwide. In this regard, this literature review aims to summarize the leading technologies and strategies developed in the state-of-the-art to mitigate the impacts of CC, as well as promote disaster risk reduction. Thus, this manuscript explains the following resilient design alternatives: anti-rutting asphalt mixtures, multilayer cool coatings, less temperature- sensitive asphalt mixtures, high-inertia pavements, flame retardancy of asphalt binders, anti-fatigue asphalt mixtures, self-healing asphalt mixtures, self-deicing asphalt mixtures, road-heating systems, fast-draining asphalt pavements, hydrophobic asphalt pavement, anti-ageing additives, solar pavements, and cool pavements. Furthermore, several constitutive models capable of simulating soil behaviour under CC-related events are introduced throughout this paper. This review highlights critical advancements in pavement engineering and encourages the adoption of sustainable, resilient design practices to safeguard infrastructure and ensure longterm socio-economic stability. The findings from this investigation provide a valuable resource for pavement designers, civil engineers, and policymakers, offering practical guidance for adapting road infrastructure to future climatic conditions.