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Occasionally there is an earthquake in the UK during which church bells are reported to have been set ringing. The motion of a medium sized church bell has been simulated and the response to earthquake records from the Parkfield earthquake of 1966 has been calculated. The response of the bells is found to depend on the mechanical properties of the bell and the tower in which it is hung. The analyses do show that for a bell to ring in an earthquake the peak ground acceleration is in the range 0.97 to 29.4 m s^-2 considerably in excess of the range indicated by the MMI VI "church and school bells ring" of 0.4 to 1.5 m s^-2. The best correlation between recognised earthquake parameters and the ringing of the bell was obtained by combining the spectral values for clapper-bell angle, obtained from the linearised set of equations, at the bells natural frequencies using the SRSS method. The values of this parameter to set the bell ringing was in the range 0.25 and 0.38 rad, compared with the actual striking angle 0.54 rad.

In this study, liquefaction and earthquake response analysis of Panipat pond ash embankment in India has been carried out considering saturated and natural water table conditions. Laboratory and field studies have been carried out to obtain the material properties required for the nonlinear response analysis of the Panipat pond ash embankment. Nonlinear finite element analysis has been carried out by using open system for earthquake engineering simulation (OpenSees). Three earthquakes namely Chamba, Chamoli and Uttarkashi earthquakes have been considered for liquefaction and earthquake response analysis. The standard penetration test (SPT)-$N$ value indicates that the ash deposit in Panipat pond ash embankment is in loose to medium dense state. The excess pore pressure ratio obtained from the analysis is found to be one or more than one below upstream and downstream locations of the pond ash embankment for both saturated and natural water table conditions. The horizontal and vertical displacement is found to be maximum near the toe and first rise slope of pond ash embankment. Hence, ash embankment in Panipat is prone to liquefaction under the excitation of moderate to high earthquake loading.

Static-Dynamic Coupling Analysis is the key technology issue for analysis of structure response in nonlinear condition. Combined with the implicit solving character of Newmark integral algorithm, a nonlinear Static-Dynamic Coupling algorithm based on improved Newmark method is raised, by studying the inner relation between nonlinear finite element dynamic and static equilibrium equations, to obtain rational nonlinear earthquake response of the structure under static and dynamic coupling excitation. The method is verified by analysis of Static-Dynamic coupling response of Fengman gravity dam in linear and nonlinear condition. The result of analysis shows that the method is effective and rational. Meanwhile, combined with abundant structure element model and nonlinear analysis of general finite element software, the method can be used in implicit solving general finite element program conveniently to carry out Static-Dynamic Coupling Analysis of various structure.