2015/9/16 -Shanghai Artificial Wave(SHW2)(上海人工波) .SHW2 is one of the Shanghai artificial wa n of a 005.The. (a)Soft soil (b)Hard soil 1.3Magnitude and Intensity Richter Magnitude .To understand the definition of"magnitude" A Richter Magnitude Scale is and"intensity" .To know the Richter Magnitude and Modified Mercalli Intensity (MMI) M2=1ogA-1og4,=10g(4/4,) MMI scale 出sw 肉大子 Magnitude(in China) Magnitude M,=logA,+R(△) ■Magnit恤eethereleased at the =log Ap+log Vo(T)-log 4-3 M=(A/T)+o(△)+C Mp=log(A/T)+Q+S logE=11.8+1.5M 62015/9/16 6  SHW2 is one of the Shanghai artificial waves, which designed for the constructions in Shanghai, according to the Code for Seismic Design of Buildings (GB50011). It imitates the seismic waves for the site classification IV in Shanghai. The damping ratio is 0.05. The PGA is 35.0 . SHW2 -0.10 -0.08 -0.06 -0.04 -0.02 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0 5 10 15 20 25 30 35 40 SHW2 0.0000 0.0005 0.0010 0.0015 0.0020 0.0025 0.0030 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 Acceleration history Power spectral density •Shanghai ArtificialWave (SHW2)（上海人工波） 2015/9/16 Haibei XIONG College of Civil Engineering, Tongji University 31 Power Spectrum of different soil (功率谱) 10 20 30 40 50 0 0 10 2 4 6 8 20 30 40 50 60 (Hz) (rad/s) (cm /s ) 2 6 12 18 24 30 0 0 10 2 4 6 8 20 30 40 50 60 (Hz) (rad/s) 2 (cm /s ) 2 2 (a) Soft soil (b) Hard soil 2015/9/16 熊海贝 同济大学 xionghaibei@tongji.edu.cn 32 1.3 Magnitude and Intensity  To understand the definition of “magnitude” and “intensity”  To know the Richter Magnitude and Modified Mercalli Intensity (MMI)  To evaluate earthquake intensity by using MMI scale 2015/9/16 熊海贝 同济大学 xionghaibei@tongji.edu.cn 33 A Richter Magnitude Scale is a base-10 logarithmic scale obtained by calculating the logarithm of the amplitude (振幅) of earthquake wave measured by a seismograph . Q4: Base on this formula, how many times for an earthquake amplitude of wave increase, when the magnitude scale increase 1? (Tips: log10=1) Richter Magnitude log log = log( / ) M A A A A L 0 0   Elcentro -0.10 -0.08 -0.06 -0.04 -0.02 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0 10 20 30 40 50 60  The Richter Magnitude Scale (abbreviated RMS, denoted as ML ) 2015/9/16 Haibei XIONG College of Civil Engineering, Tongji University 34 Magnitude (in China) P   P 0 0 log +R = log +log V ( ) log M A L A T A 3     B M A Q S  log( / T)+ + M A T S   ( / )+ +C    ML,MS ,MB：Magnitude obtained from Near Earthquake, Surface Wave and Body Wave T ：Period corresponding to A or V, σ(Δ) , Q: started calculation function , C,S: Adjusted value of seismic station. 2015/9/16 熊海贝 同济大学 xionghaibei@tongji.edu.cn 35  Magnitude measures the energy released at the source of the earthquake. Magnitude is determined from measurements on seismographs(地震仪) . Magnitude log E 11.8 1.5M Example: If M increase 1, how about the energy increase? tips: the log E=1.5, it means E = 101.5 = 31.6 2015/9/16 Haibei XIONG College of Civil Engineering, Tongji University 36