Is It normal to keep log file larger than data file?
If you have a huge modification going on, then yes, it can be normal to have a log file larger than your data file. After the huge modification is over, and the log backup is done, the file will not shrink back to it's original size however. But the file will be empty.
You can see this in Management Studio, if you right-click on the database and select Reports->Disk Usage.



I don't recommend shrinking your log file as it will only grow back the next time it needs space. But, if you are running out of disk space, know that it is possible to shrink your log file. I just don't do it, as the space gets used every time it needs to and as it's a better practice to leave it as it is.