Spring and damper system for turbine shrouds

The damper system includes a ceramic composite shroud (12) in part defining the hot gas path of a turbine and a spring-biased piston (32) and damper block (16) which bears against the backside surface (22) of the shroud to tune the vibratory response of the shroud relative to pressure pulses of the hot gas path in a manner to avoid near or resonant frequency response. The damper block has projections (20) specifically located to bear against the shroud to dampen the frequency response of the shroud and provide a thermal insulating layer between the shroud and the damper block.