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SUMMARYTwo models are tested on a shake-table. One of the models is a normal reinforced concrete megaframe structure and the other is a multifunctional vibration-absorption reinforced concrete megaframe structure in which the laminated rubber bearings are placed between the major frame and the minor frames. Two earthquake motions (the El Centro wave and the Taft wave) are used during the test. This paper presents the dynamic characteristic, the seismic responses and the failure mechanism of these two models under varying peak acceleration levels for each of the earthquake motions. The test results demonstrate that the aseismic behavior of a multifunctional vibration-absorption reinforced concrete megaframe structure is much better than that of a normal reinforced concrete megaframe structure.

To investigate fire-resistance behaviors of simple supported reinforced concrete (RC) beams with three faces exposed to fire, six full-scale specimens were designed in accordance with the principle of “strong bending and weak shearing.” One beam was treated as the control case of room temperature while the other five beams were exposed to high temperature. Parameters related to shear capacity were discussed, such as longitudinal reinforcement ratio and stirrup ratio. The experimental results show that brittle shear failure under room temperature may transfer to shear-bend failure at high temperature due to thermal expansion and strength degradation of concrete and steel. The greater the longitudinal reinforcement ratio, the longer the failure time of specimens. It indicates that the pinning action of longitudinal reinforcement can significantly improve the shear capacity of beams under high temperature. In addition, the configuration of stirrup reinforcement can effectively reduce the brittle change of vertical deflection when the beam enters the failure stage.

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The grouted precast buildings have great economic superiorities and application potentials. With excessively utilized confinement steels, connecting steels, and steel sleeves, their mechanical properties satisfied the strength requirements. But the capacity calculation approach still remains uncertain due to the complexity caused by the joint interface slip and joint gap opening displacement, which can hardly be avoided and lead to an excessive steel configuration. In order to make the design approach of precast grouted shear wall convenient and to achieve economic superiorities and properties advances, this paper proposed a new flexural capacity calculation approach considering joint interface displacements influences and properties improvement by confinement steels. The calculated capacities of example precast shear wall are 553.8 kN, 501.0 kN, and 536.4 kN when only considering confinement improvement, interface slip reduction, and both the improvement and reduction, respectively. By comparing the calculated results with the experimental tested results of 589.4 kN, the accuracy and reasonability of this new calculation approach were verified. Afterward, some requirements on application conditions of this new calculation approach were suggested depending on different precast structure type and seismic area.