Is it possible to read 5 accelerometer, BMA180, simultaneously(exactly at the same time)?
No, and there is no reason to try. The accelerometer has its own clock, and collects data points asynchronously, so you can't know exactly when the samples are collected. Also, it takes some time to read out the data.
If you have a way of accurately knowing the time, store a timestamp with each reading, and reconstruct the data along with the timing later.