The energy required for the heating and cooling of buildings is strongly dependant on the thermal properties of the construction material. Cement mortar is a common construction material that is widely used in buildings. The main aim of this study is to assess the thermal properties of cement mortar in terms of its ther­mal conductivity, heat capacity and thermal diffusivity in a wide range of grades (cement: sand ratio between 1:2 and 1:8). As there is insufficient information to predict the thermal conductivity and diffusivity of a cement mortar from its physical and mechanical properties, the relationships between thermal conductivity and diffu­sivity and density, compressive strength, water absorption and porosity are also discussed. Our results indicate that, for a cement mortar with a 28-day compressive strength in the range of 6–60 MPa, thermal conductivity, specific heat and thermal diffusivity are in the range of 1.5–2.7 W/(m.K), 0.87–1.04 kJ/kg.K and 0.89–1.26 (x10^-6 m²/s), respectively. The scanning electron microscope (SEM) images showed that pore size varied from 18 μm to 946 μm for samples with different cement-to-sand ratios. The porosity of cement mortar has a signifi­cant effect on its thermal and physical properties. For this reason, thermal conductivity and thermal diffusivity was greater in cement mortar samples with a higher density and compressive strength.

Roller-compacted concrete pavement (RCCP), named from a construction method, is a drier mix-stiff enough to be compacted by a vibratory roller. RCCP's fresh and hardened properties are considerably influenced by a mix water. The maximum density method, having optimum moisture content at maximum dry density, is most commonly used for the mix proportioning of RCCP. In this study, engineering properties of RCCP at different moisture contents of 4.5%, 5%, 5.5%, 6%, 6.5%, 7% and 12% cement were investigated. Test results showed that an increase of moisture content from 4.5% to 7% decreases the Vebe time from 45 to 22 s. The RCCP at 5.7% moisture content had the maximum dry density, while best mechanical performance, lowest porosity and water absorption values were obtained at 5% moisture content. This study concluded that a workable, high strength and durable RCCP can be made with a moisture content less than the optimum moisture content, which is corresponding to the maximum dry density.

This study provides an overview of how phase change materials (PCMs) can improve the resistance of concrete pavement to freeze–thaw cycles and mitigate the urban heat island (UHI) effect. The investigation covers different types of PCMs and methods for integrating them into concrete pavement, as well as the mechanical properties and compressive strength of concrete pavement when employing various PCMs. Prior studies have identified porous aggregates, microencapsulation, and pipelines containing liquid PCM as common approaches for PCM integration. Researchers have observed that the utilization of PCMs in concrete pavement yields favorable thermal properties, suggesting the potential for anti-freezing and UHI mitigation applications. However, the choice of PCM materials should be informed by local climate conditions.

Aggregate gradation is one of the most important property that influence the behaviour of roller-compacted concrete pavement (RCCP). There are some limitations for gradation of coarse and fine aggregates from the standards. Based on the ACI 211.3R, the content of sand size less than 75 μm should be between 2 to 8% of the total aggregates. To study the effectiveness of using a nonstandard sand (a sand with a gradation out of the specified restrictions) on the properties of RCCP, three types of sand with a difference in very fine particles content were used. The sands used are: 1) standard sand, 2) modified sands containing about 6% limestone powder, and 3) a low fines content sand containing <1% very fine particles. Two types of RCCP containing 12 and 15% cement were used as control mix. The results show that using low fines content sand or limestone modified sand instead of standard sand in RCCP increased Vebe time. The use of low fines content sand in RCCP did not have significant effect on the compressive, splitting tensile and flexural tensile strengths. However, the use of limestone modified sand in the RCCP significantly reduced the mechanical properties. RCCP was made of low fines content sand had more porosity than RCCP with standard sand. It can be concluded from test results that sand with lack in very fine particles can be used in RCCP.

The mechanical and thermal properties of roller compacted concrete pavement (RCCP) are considerably influenced by its aggregate. This study determined the optimum value of lightweight expanded clay aggregate (LECA) incorporation into the RCCP through the response surface methodology (RSM) with mechanical and thermal properties evaluation. LECA was replaced as coarse aggregate in different percentages of 25, 50, 75, and 100% (by volume) to develop lightweight and high-insulation capacity RCCP, which could be appropriate for cold climatic zones. Two different mixtures of RCCP with normal-weight aggregate comprising 12% and 15% cement were used as control mixtures. The results showed that incorporating LECA at any percentage in RCCP produced more workable concrete. The substitution of LECA in 25–100% decreased the density of RCCPs containing 12% and 15% cement about 8–24% and 7–23%, respectively, while the water absorption increased around 4–77% and 8–72%. The thermal conductivity of RCCPs decreased by increasing the LECA replacement as coarse aggregate. Also, the LECA replacement increment in RCCPs resulted in lower heat capacity values. Overall, it can be concluded that incorporating LECA in RCCP by around 37% as coarse aggregate would satisfy the standards in terms of fresh, mechanical, and thermal properties.