Use this method to install trials for WAS 8 using a similar process to the official product installation process.
Get download from : https://www-304.ibm.com/support/docview.wss?uid=swg24029226
[https://www-304.ibm.com/support/docview.wss?uid=swg24029226#downloads]
Note: these images show version 1.4.4 (at least 1.4.3 is required by WAS 8 trials)
agent.installer.linux.gtk.x86.zip is what I am using for this document.
once on server, decompress
./install
Accept License and click Next
Review path and clink Next