Based on forced vibration tests for high-performance concrete (HPC), the influence of bridge vibration induced by traveling vehicle on compressive strength and durability of HPC has been studied. It is concluded that 1 d and 2 d compressive strength of HPC decreased significantly, and the maximum reduction rate is 9.1%, while 28 d compressive strength of HPC had a slight lower with a 3% maximal drop under the action of two simple harmonic vibrations with 2 Hz, 3 mm amplitude, and 4 Hz, 3 mm amplitude. Moreover, the vibration had a slight effect on the compressive strength of HPC when the simple harmonic vibration had 4 Hz and 1 mm amplitude; it is indicated that the amplitude exerts a more prominent influence on the earlier compressive strength with the comparison of the frequency. In addition, the impact of simple harmonic vibration on durability of HPC can be ignored; this shows the self-healing function of concrete resulting from later hydration reaction. Thus, the research achievements mentioned above can contribute to learning the laws by which bridge vibration affects the properties of concrete and provide technical support for the design and construction of the bridge deck pavement maintenance.

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In situ leaching (ISL) is becoming the main mining practice for sandstone-type uranium deposits in China. The key to ISL technology is to aid the leaching solution in contacting the ore bed over a large range, which will induce a series of chemical reactions to extract uranium; thus, it is essential to thoroughly understand the reservoir physical properties of uranium deposits. Taking the Qianjiadian sandstone-type uranium deposits (southern Songliao Basin, China) as an example, the mineral composition and pore structure of samples in different layers were measured using X-ray diffraction (XRD), thin section analysis (TSA), low-temperature N2 adsorption (LTN2A), and mercury intrusion porosimetry (MIP), and their influences on the ISL effect were analyzed. The results show that more than 65% of the minerals in the Qianjiadian uranium deposits are felsic minerals, and the carbonate minerals, clay minerals, and augite are auxiliary minerals. The primary intergranular pores, intergranular-dissolved pores, intragranular-dissolved pores, intercrystalline pores, and microfractures are developed in uranium deposits with various lithologies to different degrees. The macropores ( >1000 nm) and mesopores (100-1000 nm) of medium sandstone, argillaceous sandstone, and siltstone are well developed; in contrast, the proportions of micropores ( <10 nm) and transition pores (10-100 nm) in coarse sandstone, fine sandstone, and sandy mudstone are quite high. The heterogeneity of pores in uranium deposits of different lithologies is strong and influences the mineral composition and its fabric mode. Coarse sandstone, fine sandstone, and sandy mudstone are favorable for ISL mining in Qianjiadian uranium deposits because their permeability is above the required permeability threshold of ISL. The uranium deposits with permeability below the threshold are recommended to adopt the blasting-enhanced permeability method to improve their permeability for achieving large-scale and high-efficiency ISL mining. This study can provide guidance for the selection of favorable ore beds for ISL mining and reservoir stimulation methods in low-permeability sandstone-type uranium deposits.