Anti-seismic Behavior Analysis Of Fire Protection Pipe Network In Grooved Couplings Style

Pipe network is a core component in fire protection engineering field with the keyposition and high importance,which can reflect the security performance of fire protection engineering and system.During the earthquake disaster,the buildings can cause several kinds of damages due to insufficient structural bearing capacity,loss of structural integrity,foundation failure etc.Also,the vibration of pipe network is extremely severe because of the multi-point impact from different kinds of seismic waves.For this reason,the piping stress state and movement law is extremely complex,which leads to severe engineering fault by the leakage and breakdown before the scheduled life index.The main cause is that stochastic motion and failure mode of the pipe network under the extreme conditions are hard to forecast,which is extremely difficult to meet the requirements of anti-seismic design under the strong impact condition.Therefore,the analysis and research on dynamic characteristics and anti-seismic behavior of fire protection pipe network are of great theoretical value and engineering significance.In this paper,a grooved flexible couplings fire protection pipe network is taken as an example,to research and analyze the anti-seismic behavior,and the main research contents and conclusions are as follows:(1)The energy dissipation mechanism of fire protection pipe network influenced by seismic action: the stochastic vibration excitations of seismic waves,the hysteretic energy dissipation mechanism of viscoelastic material,the clearance between flexible couplings and pipe ends are comprehensively taken into account,the relationship equation between strain and stress of rubber seal gaskets and the structure resilience model of couplings viscoelastic damper are established.In addition,the energy conversion method based on energy conservation principle is proposed,and then the energy response and seismic movement differential equations of fire protection pipe network are deduced.Thus,the energy dissipation mode of seismic movements is analyzed,which can provide theoretical models foundation for FEA anti-seismic simulation of fire protection pipe network.(2)The anti-seismic design requirements and analysis methods of fire protection pipe network: according to the specification requirements for seismic design of mechanical and electrical equipment,based on the definition of mode-superposition response spectrum and time-history analysis,along with the structure and seismic movement differential equations offire protection pipe network,the dynamical model diagram of multi-particle fire protection pipe network is established.Then,the particle displacement calculation formula and the quasi static equation are deduced,the methods of response spectrum and time-history analysis that belongs to fire protection pipe network are revealed,which can provide the theoretical methods for anti-seismic case analysis of fire protection pipe network.(3)The anti-seismic behavior case analysis of fire protection pipe network: to further verify the validity and practicability of the model and method,a practical case is selected.Modal analysis and response spectrum analysis are simulated based on ANSYS workbench FEA software.Also,time-history analysis is simulated by individually inputting EI Centro,Taft and artificial synthetic seismic waves.Then,the simulated results between response spectrum and time-history analysis are contrasted,which can analyze if the simulated results can meet the requirements of the seismic design code of mechanical and electrical equipment.In addition,the anti-seismic tests are run,and the measured data from displacement and acceleration is used for validating the accuracy and reliability of simulated results in time-history analysis.