Summary Energy plays an important role in a fast‐paced modern society. With the depletion of fossil energy, effective utilization of solar energy is getting increasingly urgent. Thermal energy storage is an inevitable choice for effective utilization of renewable energy sources. As one of the most promising renewable energy sources, solar energy is inexhaustible. But it has some shortcomings such as instability and intermittency, affected by time, climate, and geographical location. Thermal energy storage technology, which can effectively reduce the cost of concentrated solar power generation, plays a crucial role in bridging the gap between energy supply and demand. In addition, thermal energy storage subsystem can improve performance and reliability of the whole energy system. According to different principles, thermal storage technology is generally classified as sensible heat storage, latent heat storage, and thermochemical energy storage. Most solar thermal power generation systems, currently demonstrated and operated in the world, adopt the method of sensible thermal energy storage. In contrast, thermochemical energy storage is a relatively new concept, which is still in the stage of basic test and verification. Thermochemical energy storage technology stores and releases energy through endothermic and exothermic reversible reactions. A closed system with separated reactants and products, in theory, can store energy indefinitely. The main thermochemical energy storage systems include redox system, metal hydride system, carbonate decomposition system, ammonia decomposition system, methane reforming system, and inorganic hydroxide system.

An investigation of girder bridges on National Highway 213 and the Doujiangyan-Wenchuan expressway after the Wenchuan earthquake showed that typical types of damage included: span collapses due to unseating at expansion joints; shear key failure; and damage of the expansion joint due to the slide-induced large relative displacement between the bottom of the girder and the top of the laminated-rubber bearing. This slide, however, can actually act as a form of isolation for the substructure, and as a result, the piers and foundation of most of the bridges on state route 213 suffered minor damage. The exception was the Baihua Bridge, which suffered severe damage. Corresponding seismic design recommendations are presented based on this investigation.

With increasing traffic congestion happening across the world nowadays in the busy highway bridge systems and urban areas, seismic interaction between vehicle and bridge is a subject that has attracted increasing research interests. A few studies were conducted in recent years. There seems to be a cursory consensus that the behavior of vehicle is similar to a tuned-mass-damper and usually results in beneficial effect to bridge seismic responses. However, the mechanism of seismic interaction between vehicle and bridge still remains unclear. Present study statistically investigates the seismic responses of both vehicle and bridge under real earthquakes and a reasonable explanation as to the interaction mechanism between vehicle and bridge is given based on energy analysis. The results show that dynamic interaction would affect the energy distribution between vehicle and bridge. Vehicle has little influence on seismic responses of bridge in the horizontal directions because of the change of energy imparted to bridge caused by vehicle is very small. On the contrary, vehicle responses in the horizontal directions, under some circumstances, are extremely large as a result of relatively large energy imparted from bridge to vehicle. In the vertical direction, a surge of energy imparted to bridge, at some instant of time, caused by vertical compression force between vehicle and bridge could result in significant increases in peak responses of bridge. However, the total input energy imparted to bridge over the duration of earthquake is reduced lessening the overall damage of bridge.

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