| Stability of single-layer spherical shells is the key problem on the structural design. When analyzing stability of shells, it is important to choose structural accurate calculation-mode. In general, people act shells with weld-joint system as shells with rigid-joint system and act shells with bolt-joint system as shells with pin-joint system. Because the ultimate strength of single-layer shells with pin-joint system is quite low, shells with bolt-joint system have not been extensive applied in project. In fact, bolt-joint has capacity of bearing partial bend, it is semi-rigid system between rigid-joint and pin-joint. So the single-layer shells with bolt-joint system are not shells with pin-joint as traditional point of view, but are typical shells with semi-rigidity which have capacity of bearing severally loads.Entitative model of bolt joint system has been established firstly in the discourse, and testified correctly through typical examples, which provide reference for new type of semi-rigidity of joint system. Bend stiffness of common bolt joint system has been obtained.Numerical model of shell with semi-rigidity of joint system has been established in this dissertation, which provides a effective and convenient method for analysis shell with semi-rigidity of joint system. The shells with bolt-joint system have been detailed analyzed in this dissertation based on bend stiffness of common bolt joint system, Eight hundred of the elastic plastic complete process of k8 and k6 spherical shells are studied in this base, the ultimate strength and buckling modes of shells are obtained, the effects of stability are observed systematically by varying different spans of shells, ratio of high and span, bend stiffness ,rotation stiffness, the size of joint system, the load of dissymmetrical distributing, the types of bars, the condition of support and initial geometrical imperfection. The stability of shells with semi-rigidity of joint system is mastered by a comprehensive numerical analysis.
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