I have a set of 1055 brakes (same as yours but long reach) and the barrel adjuster is just threaded into the caliper arm with a tension spring and a notched plastic collar to keep it from turning from vibration. If your adjuster turns but doesnt rise or fall then either the adjuster barrel or the caliper arm threads are damaged. Try unscrewing it while pulling up to get it out of the caliper. Then examine it to see which part is bad. If the barrel itself is stripped any 6 mm barrel should be a suitable replacement. If the arm is stripped, add a nut to the barrel and use that to adjust it's height.