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Pulsed power technology, whereas the electrical energy stored in a relative long period is released in much shorter timescale, is an efficient method to create high energy density physics (HEDP) conditions in laboratory. Around the beginning of this century, China Academy of Engineering Physics (CAEP) began to build some experimental facilities for HEDP investigations, among which the Primary Test Stand (PTS), a multi-module pulsed power facility with a nominal current of 10 MA and a current rising time ∼90 ns, is an important achievement on the roadmap of the electro-magnetically driven inertial confinement fusion (ICF) researches. PTS is the first pulsed power facility beyond 10 TW in China. Therefore, all the technologies have to be demonstrated, and all the engineering issues have to be overcome. In this article, the research outline, key technologies and the preliminary HEDP experiments are reviewed. Prospects on HEDP research on PTS and pulsed power development for the next step are also discussed.

In view of the problems of traditional repair materials for anchorage concrete of expansion joints, such as ease of damage and long maintenance cycles, the design of polyurethane concrete was optimized in this article, which could be used for rapid repair of concrete in anchorage zone of expansion joints. A new type of carbon fiber grid–polyurethane concrete system was designed, which makes the carbon fiber grid have an excellent synergistic effect with the quick-hardening and high-strength polyurethane concrete, and improved the flexural bearing capacity of the polyurethane concrete. Through the four-point bending test, the influence of the parameters such as the number of grid layers, grid width, and grid density on the flexural bearing capacity of polyurethane concrete beams was tested. The optimum preparation process parameters of carbon fiber grid were obtained to improve the flexural performance of polyurethane concrete. Compared with the Normal specimen, C-80-1’s average flexural strength increased by 47.7%, the failure strain along the beam height increased by 431.1%, and the failure strain at the bottom of the beam increased by 68.9%. The best width of the carbon fiber grid was 80 mm, and the best number of reinforcement layers was one layer. The test results show that the carbon fiber grid could improve the flexural bearing capacity of polyurethane concrete. The carbon fiber grid–polyurethane concrete system provides a new idea for rapid repair of the anchorage zone of bridge expansion joints, and solves the problems such as ease of damage and long maintenance cycles of traditional repair materials, which can be widely used in the future.

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