The consecutive multiple impact resistance of reinforced concrete pier column becomes the most concern in the engineering field. Numerical simulation the process of consecutive multiple lateral impacts is the necessary measures to master the internal mechanism. The fine 3D finite element model is established combining solid element and beam element. The dynamic damage constitutive model of concrete is developed. To react to problem of calculative efficiency and damage accumulation effect, the reduced integration method and full restart analytical method of explicit dynamic analysis strategy is taken using element failure criterion. The translation process of the system energy, the time history value of impact mass acceleration and strain gauge and failure mode of the reinforced concrete pier are compared with the experiment results. The feasibility of the modelling and the validity of the analysis strategy are validated. This study can provide computation basis for research of reinforced concrete structures under consecutive multiple impact.

Due to high power density and reactivity compared with the use of gaseous hydrogen as the fuel, direct borohydride fuel cell (DBFC) is becoming an emerging renewable energy source. In this paper, DBFC characteristic is analyzed based on the frequency response measurement and test with different load conditions. The equivalent circuit of DBFC is obtained from the DBFC characteristic. A dc-dc converter is designed from the frequency domain and verified its performance at time domain with transient load test. Based on the combined model analysis of DBFC and the dc-dc converter, transient response of the model is discussed. In addition, load transient response tests with power supply and DBFC have been compared. A prototype of dc-dc boost converter for 5-cell DBFC has been built and tested.