Yes it is possible to do this but it is not simple. Simply put you have to create an object the shape of the arch to represent the bricks, and add it to the top of your archway, attaching it to the wall so to speak. You can then apply a suitable texture. (See the link below).
Another option is to use a photo of such an arch applying it to the wall as a full image (not a tiled one).
A third option is to create a "photoboard" of the arch. This is in affect a floating photo of the arch bricks positioned in front of the archway. The photo is rectangular but you can make it all invisible except the brick arch itself but setting the colour to true Magenta (Red 255, Green 255 and Yellow 255) and save it as a BMP file. Magenta become invisible in TFP. The image must be a BMP not JPG - otherwise you will have a pink fringe around your arch. You import the photo as a "photoboard" and position it against the wall and resize it to fit.
Unfortunately these soltions are not really easy unless you are very familiar with the program and its capabilities.
The following link provides some details, and has links within it to more detail. I hope it helps.http://forums.turbofloorplan.com/index.php/topic,1319.msg6485.html#msg6485