for the other problem of time period vs. maximum response the input and output layer contain the time period and the corresponding maximum response respectively at each interval for the particular structure. 

## 5 Numerical Results And Discussions

For the present study two Indian earthquakes viz. the Chamoli Earthquake (max. ground acceleration =0.16885 m/sec/sec) at Barkot in NE (north–east) direction shown in Fig.2(a) and the Uttarkashi earthquake (maximum ground acceleration = 0.931 m/sec/sec) at Barkot in NE (north–east) and NW (north-west) direction as given in Figs. 2(b) and 2(c) have been considered for training and testing. Initially, the system without damping is studied and for that the ground acceleration of Chamoli earthquake at Barkot (NE) was used to compute the response for single storey structure using usual procedure from Eq.(3). The obtained response and the ground acceleration is trained first for the assumed frequency parameters ω=0.5 and ω**=0.01 for time range 0 to 14.92 sec.(748 data** 
points) for the mentioned earthquake. Simulations have been done for different hidden layer nodes and it was seen that the response result is almost same and good for 5 to 20 nodes in the hidden layer. However, 10 hidden layer nodes are used here to generate further results. 

After training ground acceleration and response data for Chamoli earthquake at Barkot (NE) for 10 nodes in hidden layer, the weights are stored and they are used to predict responses for various intensity earthquakes. The plot in Fig. 3(a) shows response comparison between neural and desired for the 80% of Chamoli earthquake at Barkot (NE) for ω**=0.01(maximum response=0.135079m/sec/sec).** Similarly, the response comparison for 120% Chamoli earthquake at Barkot (NE) 
for ω**=0.5 (Maximum response=0.20260 m/sec/sec) is shown in Fig 3(b).** 
Next, a part of the ground acceleration is used for the training and it will be shown that the present ANN can predict the whole period of the response using the trained ANN by the part of the data. So, the ground acceleration and 