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Cold mix recycled asphalt (CMRA) concrete was evaluated to be an innovative repair material to improve the pavement quality and environmental impact on pipeline maintenance in this study. The study presented and specifically examined the use of CMRA with 2.5 % foam asphalt content as a replacement for the currently used controlled low-strength material (CLSM) as pipeline backfill material. CMRA’s material properties, performance, carbon dioxide emissions, cost, and construction time were analyzed in this study to confirm the advantages and limitations of CMRA. The results concluded that CMRA performed better than CLSM for all the items analyzed. Specifically, according to the performance analysis, CMRA exhibited a better Marshall stability index, California bearing ratio, indirect tensile strength, tensile strength ratio, anti-rutting ability, and penetration than the standards specified. Furthermore, the average carbon emissions of CMRA were 36 % less than CLSM, could save at least 2 h of construction time per cubic meter of construction, and immediately opened traffic. However, CRMA’s construction cost in this study was similar to CLSM and was only lower (up to 2.3 %) by considering a similar price of cement, asphalt, and additives. Based on the aforementioned results, this study concluded that the findings may be of particular interest for Taiwanese pipeline maintenance projects as a backfill material and is worthy of further research.

This study explored the thermal behavior of permeable pavement during summer. T-type thermo-couple needle was utilized to measure the surface temperature of three different permeable pavement materials. Data were measured based upon the 24 solar terms of the traditional Chinese lunisolar calendar and the results of Great Heat in comparison with other solar terms showed significant differences. Heat output model calculation results show that the average heat output is the lowest for grass bricks because of its high reflectivity. This material has a cooling effect, followed by permeable interlocking bricks. Permeable asphalt concrete can reduce pavement temperature but there were limitations to its performance.

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Cold-mix asphalt has been developed in recent years by combining foamed asphalt and recycled asphalt pavement (RAP). However, manufacturers struggled due to the less standardized specification. Foaming and mixing performance cannot be accurately controlled and are usually treated with a foaming agent (FA). This research focused on the relationship between the chemical composition of bitumen and its foaming properties. Three groups of AC-20 bitumen and organo-modified siloxanes based FA with water content of 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0% and 4.5%. were analyzed. Chemical components of different bitumen types were evaluated using the Gaestel colloidal index (CI). The half-life (HL), expansion ratio (ER), Foam index (FI), and bubble surface area index (SAI) were used to evaluate the workability of the binders and discuss the effects of the values on the performance of the mixture. The CI observation revealed that FA obviously changed the saturates value and greatly improved the foam properties in terms of stability and expansion. FI change was found to be 71% of the change in the CI. Similarly, the resulting FI and SAI reach up to 88% in terms of correlation.