Hello amir ali,
By design the RadSplitter does not offer removing the titlebar but you can achieve what you need by going through the following steps:
1) set EnableDock="false" for all the sliding panes
2) Include the following CSS in the page's head:
Note the usage of the keuword !important
because if you miss it, your custom settings will get overridden by the default ones and you will not get the desired result.
The solution I prepared for you and suggested works fine on my side, let me know whether tit works for you as well.
the Telerik team