Did you even bother checking the console for an error report? Because it would have gave an error about this:
datablock fxDTSBrickData (brickWedgeRoadData : brickWedgeRoadData)
Basically the colon means inheritance. The datablock on the left of the colon (the new datablock you're creating) inherits from the datablock the on right of the colon (an already existing datablock). The new datablock will copy all members from the existing datablock, and you can change or add members inside the definition. What you're trying to do here is make a datablock inherit from itself. This makes no sense, especially as the datablock you're trying to inherit from doesn't exist yet.
Also, it needs a uiName.