Design And Research On A New Type Of Roller Ball Seismic Isolator

Rolling ball isolation is one important form of base isolation. It has the characteristics of good stability, function of restrict displacement and restoration and prominent islation effect, etc. That is an effective way to protect structures from damage in severe earthquake and can ensure the safety of people's lives and properties. Many domestic and foreign scholars have conducted a simple theory analysis about its dynamic properties, but not in-depth. Because of its complexity, there are still many technical problems to be resolved, since now China is still no formal technical regulations to guide the design of such isolated structures. So this study has its major theoretical and practical value.On the basis of the analysis to existing roller ball base isolation devices, using the shape memory alloy and disk springs, This paper designs a new type of ball isolation device, and to demonstrate the feasibility of the device through theory and simulation analysis.The main contents are as follow:1 Two kinds of isolation devices are introduced: rolling spheres with re-centering isolation device and rolling spheres with concave-board isolation device. And differential equations of motion of the latter are established.2 Combinating of the shape memory alloy materials,this paper designs a new type of ball isolation device, analyses its dynamic response and set up the motion differential equations.3 Using MATLAB programming, this paper contrasts the three structures: rolling spheres with concave-board isolation structure, rolling spheres with concave-board and SMA isolation structure, fixed base structure. And the new isolation device is optimized.4 Using MATLAB programming, this paper establishes interlaminar shear model and carries out nonlinear dynamic analysis to the isolated and not isolated structures, comparing the reactions.5 Add disk springs at the base of the new roller ball isolator, and analyse the vertical seismic response.