Novel ordered hierarchical mesoporous/microporous carbon (OHMMC) derived from mesoporous titanium-carbide/carbon composites was prepared for the fi rst time by synthesizing ordered mesoporous nanocrystalline titanium-carbide/carbon composites, followed by chlorination of titanium carbides. The mesostructure and microstructure can be conveniently tuned by controlling the TiC contents of mesoporous TiC/C composite precursor, and chlorination temperature. By optimal condition, the OHMMC has a high surface area (1917 m 2 g − 1 ), large pore volumes (1.24 cm 3 g − 1 ), narrow mesopore-size distributions (centered at about 3 nm), and micropore size of 0.69 and 1.25 nm, and shows a great potential as electrode for supercapacitor applications: it exhibits a high capacitance of 146 Fg − 1 in noaqueous electrolyte and excellent rate capability. The ordered mesoporous channel pores are favorable for retention and immersion of the electrolyte, providing a more favorable path for electrolyte penetration and transportation to achieve promising rate capability performance. Meanwhile, the micropores drilled on the mesopore-walls can increase the specifi c surface area to provide more sites for charge storage.

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This paper presents the rehabilitation project of Dabanshan highland road tunnel. Cause analysis is carried by insight into the information of climate, geological, hydrological condition, tunnel defects type and parameters. Water leakage, low temperature and poor rock condition are considered to be source of tunnel defects, and the essential of rehabilitation of highland road tunnel are water leakage treatment and heat preservation system reinstatement. Measures taken to solve the problems of cracks, water leakage and frost are introduced in detail, and results show that measures taken are proved to be effective. Knowledge and experience gained are helpful for similar projects in future.

Void between road tunnel liner and surrounding rock is one of the most frequent defects in tunnel engineering. In this paper, contact method is introduced into the numerical model to simulate the interaction between tunnel liner and surrounding rock. The relationship between the key parameters of void and safety factor of the structure is systematically studied with the numerical model. Results show that position and width of void are the key parameters, while depth and shape of void are unimportant and negligible. It can also be concluded that the decrease rate of safety factor to the increase of circular width is almost the same while void is in different position. Conclusions gained are helpful for inspection, operation status assessment and rehabilitation of road tunnel in future.

This paper presents defects inspection and cause analysis of six road tunnels in Chongqing based on information of construction, operation and maintenance, defects property and related factors. The unfavorable factors including ground disturbance and load nearby, complex structure form, construction deformation that threaten the safety of tunnel structure and operation are thoroughly analyzed. Based on the discussion and analysis recommendation and suggestion on measures of urban tunnel maintenance and management are carried out. Experience gained is helpful for future urban road tunnel maintenance and management.