hi,
ex. a triac triggered at 0 degrees, cutted at 90, triggered at 180 and cutted again at 270 degress wouldn't generate a waveform that has an effective voltage of 60V?

But what is about waveform of the output signal? It is broken and not sine. So these 60V are "in theory". Just imagine that this signal is passed to some device which accepts sine wave AC. I doubt it will be still working correct...

Regards,
Oleg