| Construction industrialization has become the most significant development trend in our country’s building field.The key path of construction industrialization is prefabricated construction,whose core is developing prefabricated structure.In recent years,the prestressed fabricated structure has emerged as the best prefabricated structure because of its excellent construction efficiency and recovery ability after earthquake.However,there are still some problems such as poor energy dissipation and weak seismic capacity under earthquake.Therefore,a new type of friction articulated prestressed frame structure was proposed to improve the energy dissipation performance by introducing friction energy dissipation mechanism which rotate on the positive in beam-column joints.In this thesis,a series of studies on energy dissipation characteristics of friction articulated prestressed prefabricated beam-column frame element were carried out.The main contents are as follows:(1)The non-linear analysis model of friction articulated prestressed prefabricated beam-column frame element was established by using finite element software ABAQUS.The pseudo static loading process of a frame element was analyzed and calculated,which obtained the moment of sliding,ultimate moment hysteresis curve and failure mode of the frame element.They provided the basis of subsequent experimental design.(2)Six friction articulated frame element assembled by pre-compression and one cast-in-place frame element of the same scale as the actual structure were designed and manufactured.A series of energy dissipation indexes such as hysteresis curve,skeleton curve,energy dissipation value and energy dissipation coefficient of the frame element were obtained in low cycle reciprocating loading pseudo-static test.The energy dissipation characteristics of the friction articulated prestressed prefabricated frame element were comprehensively evaluated,which found it is obviously superior to cast-in-place frame element.(3)Based on the test results,the influence of interface prestressed stress on energy dissipation of joints was investigated.It was found that the greater the interface prestressed stress is,the more difficult to rotate the structure interface and the stronger the energy dissipation capacity of joints is.Then,the impact of the curvature radius of bracket on the energy dissipation characteristics of joints was inspected,which found with the increase of the curvature radius,the sliding load and the energy dissipation value of the interface increase,but the energy dissipation coefficient of components decreases.Besides,the investigation of the influence of steel strand length on the energy dissipation characteristics of joints was carried out.It showed that the shorter the strand length is,the greater the required load for the interface sliding is,and the more the energy dissipation of the interface is.However,the relationship between the ener-gy dissipation coefficient of the structure and the strand length is not simply linear.Finally,the impact of the beam and column flexures on the energy dissipation characteristics of the structure was inspected.The frame element can dissipate energy not only by sliding friction between interfaces,but also by elastic-plastic deformations of beam and column under earthquake. |
