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High-modulus asphalt mixtures (HMAM) have been widely used in asphalt pavement in high-temperature areas of China, owing to their advantages in rutting and fatigue resistance. However, moisture and temperature interdependently determine the degradation of pavement performance of the HMAM, owing to the unique climatic conditions in summer in some high-temperature areas of China. There were few studies on the rutting and fatigue properties of the HMAM under the combined action of moisture contents and temperatures. Hence, the moisture absorption characteristics of the HMAM at different temperatures were analyzed. The rutting performance of the HMAM was investigated under different moisture contents and temperatures. The fatigue performance of the HMAM was investigated under different moisture contents, temperatures, and stress levels. Results show that: the rutting and fatigue resistance of the HMAM decrease with the increase in temperature and moisture content. The dynamic stability decreases by 8.9% at 40 °C and by 7.0% at 60 °C on average per 10% increase in moisture content and decreases by 22.7% on average per 10 °C increase in temperature. The fatigue life decreases by 4.1% at 15 °C and by 3.1% at 40 °C on average per 10% increase in moisture content and decreases by 31.3% on average per 10 °C increase in temperature. Finally, a prediction equation was established to predict the fatigue life under different moisture contents and temperatures. [ABSTRACT FROM AUTHOR]

The reinforced concrete invariably involves some diseases (e.g., crack, void, etc.) due to the complex service conditions. These diseases are usually repaired to extend the service life of reinforced concrete by using cement grouting materials. In order to meet a certain color need of reinforced concrete, toner is mixed into the cement grouting materials. However, the toner has a negative effect on the early strength of cement grouting materials. Unfortunately, the mechanism of the negative effects of toner is still unclear, and no effective and targeted measures have been put forward. Hence, the main work of this paper reveals the mechanisms of the toner and nano-SiO2 (N-S) in the hydration process and the strength generation of the cement grouting materials in the case of different curing ages and nano-SiO2 contents via the scanning electron microscopy test (SEM), X-ray diffraction test (XRD), differential scanning calorimetry test (DSC), and Fourier transform infrared spectroscopy test (FTRI). Results show that: (a) the toner hinders the generation of AFt and CH crystals (especially for 1-day and 3-day), which delays the hydration process and weakens the early performance of cement grouting materials; (b) the N-S promotes the hydration process and the formation of C-S-H gels, so as to effectively increasing the early strength and reducing (but not eliminate) the adverse effect of toner on cement grouting materials; (c) With the increase of every 1% N-S, the flexural strength of 1-day, 3-day, and 7-day average increased by 11.3%, 2.9%, and 0.9%, respectively, and the compressive strength of 1-day, 3-day, and 7-day average increased by 0.8%, 0.3%, and 0.1%. [ABSTRACT FROM AUTHOR]