| Buildings on the slope are widely used and have been increasing in mountainous city, but the research on seismic design theory of structures on the slope has lagged behind the needs of engineering practice. Therefore, the design ground motion input problem and the lateral stiffness control method of structures on the slope are studied systemically. The achievements of this thesis are shown as follows:To satisfy the demands of the development of buildings on the slope, the concept of structures on the slope is proposed, the type of them is defined and the key problems of their seismic design are clarified. Thus the rules and requirements which should be conformed in the design of structures on the slope are verified in this thesis.Three geometric models of the structures supported by foundations with different locations are established according to engineering practice. The special problems of seismic design of typical structures on the slope are described and summarized from seismic damage investigation and engineering practice. Based on the analysis of the mechanical properties, dynamic characteristics and seismic behavior for structures supported by foundations with different locations, the special problems are summarized to three aspects: ground motion input, vertical irregularity and seismic measures.Research on the seismic input of the structures on the slope is supplemented and completed, which offers the reference to the code for seismic design of buildings. The elastic responses of 28 viscoelastic rock slope models under horizontal and vertical white noise input are analyzed by the finite-element method. And the slope height and the slope angle of the models are 10~70 meters and 15~60 degrees respectively. Furthermore, the amplification coefficients of horizontal ground motion of the structures on the rock slope are proposed, and the seismic input problem for the structures is solved; meanwhile, the amplification coefficients of vertical ground motion are proposed to the structures on the slope needing to take into account the influence of vertical ground motion.The method of calculation lateral stiffness of the structures on the slope, which is simplified via equivalent column method, is studied. And the distribution law of the internal force is revealed for the structures on the slope. Considering the influence of linear stiffness ratio between the column and beam of the losing-floor part, the method to compute the height of the equivalent column is proposed and verified properly. Furthermore, through considering the influence of rotation angle of the column end, the lateral stiffness D values of unequal height frame columns for the structures with"one story, one span"and"multilie-story, multilie-spans"are both modified.The control method of lateral stiffness of the structures on the slope is studied firstly, and the control index and some design suggestions are proposed. The main content includes the following parts: 1) The present control indexes of vertical irregularity that is the index of story shear bearing capacity and story lateral stiffness aren't applicable to the structures supported by foundations with different locations. 2) According to the characteristics of foundations with different locations, the concept of"internal story equivalent lateral rigidity ratio"is put forward to the structures supported by foundations with different locations. 3) To summarize the distributing law of elastic story drift ratio, story shear and relative yield strength ratio and the results of the elastc-plastic analysis, the index of lateral stiffness and the criterion of the weakness floors is proposed. 4) The local of the initial calculation point of the structures supported by foundations with different locations is suggested. 5) Some design suggestions of internal force adjustment of the weakness stories and ductility control of the weakness part are given.This thesis prepares the basic study and theoretical basis for the draft of the first structure on the slope design code.
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