I assume that you turned on Bridging IRB. Does your BVI show UP UP when you do a Show Ip int Brief? What do your ARP tables show? I used BVIs on two routers within the same IP subnet not quite the same thing your doing with just one side.
3550 DOES NOT support run of the mill bridging for IP, this the reason you are not able to ping between two devices in the same bridge-group. In addition the 3550 does not support BVI, for that as you are well aware it uses SVI.
These link documents "UNSUPPORTED" commands on 3550:
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...