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This study investigates the feasibility of recycling waste oil shale as an alternative material into asphalt pavements in Jilin province, China. The high-and low-temperature properties of asphalt materials play important roles for asphalt pavements in seasonal frozen regions. Laboratory experiments were conducted to analyze the high-and low-temperature properties of asphalt mastics and mixtures. Results indicated that adding oil shale ash (OSA) may lead asphalt to a softer consistency and less temperature susceptibility. Also, OSA could improve high-temperature stability and enhance rutting resistance of asphalt materials, whereas the effect of OSA on low-temperature properties is insignificant by comparison. Moreover, the high-and low-temperature performances of asphalt mixtures were evaluated based on testing roads through rutting depth index, riding quality index, and indirect tensile strength test. It can be proved that the sustainable asphalt materials have better high-temperature stability and rutting resistance and also fulfill the requirements of low-temperature cracking resistance.

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Oil shale waste ash (OSWA) can be divided into semicoke ash (SA), power plant ash (PPA), and grinding ash (GA), which changes the properties of binding materials in varying degrees as partial replacements of cement in cement concrete. Fluidity of cement paste test is formed to reflect the compatibility between binding materials and admixture, using the mixture of cement to test compressive strength, flexural strength, and brittleness coefficient, to determine the mixing ratio of OSWA. The optimal amount of OSWA replacing cement was optimized by orthogonal test method, and the mechanical properties and frost resistance durability tests were carried out to clarify the reasonable amount and properties of OSWA replacing cement with cement concrete. The results show that appropriate admixtures should be taken into account when OSWA is used to replace cement in order to achieve the workability of cement concrete. The brittleness coefficient and crack resistance of cement concrete can be improved by adding proper PPA and GA. The oil shale cement concrete should not be used in the parts that require high frost resistance. It is feasible to replace cement with OSWA, and the fine powder type and mixing amount can be selected according to the actual project demand.

Oil shale semicoke is a hazardous byproduct in oil shale retorting process. In Jilin province, China, abundant oil shale resources are mainly used for retorting shale oil accompanying with a large number of oil shale semicoke slags, which will generally cause environmental pollution and disposal problems. If oil shale semicoke can be utilized as a road base or subbase course construction material, it will be a great help to the disposal of a long-term accumulated oil shale semicoke in landfill sites. Moreover, the resource treatment of oil shale semicoke in road project construction could obtain positive social and economic benefits. Subsequently, we conducted a series of laboratory tests to study the practicability of cement-stabilized oil shale semicoke as a road base or subbase course construction material, including the raw material test, modified compaction test, unconfined compressive strength (UCS) test, splitting tensile strength (STS) test, compressive resilient modulus (CRM) test, and freezing-thawing test. In this paper, test results were compared with the technical requirements of Chinese road base construction specification, preliminarily confirming that cement-stabilized oil shale semicoke can be used as a subbase course material of a highway or a base course material of a low-grade highway.