Superconductivity of BSCCO single crystals in which some CuO2 trilayer
s are Inserted in the Bi2Sr2CaCu2O8 matrix is studied. The curvatures
of the I-V curves for CuO2 trilayers change from negative to positive
with increasing field, and the scaling behaviour of a vortex-glass sta
te is observed. I-c is found to obey the relation I-c = I-c0 (1 - T/T-
c)(alpha) with alpha = 1.2. Our results reveal that the vortex-glass t
ransition exists in the system constructed with CuO2 trilayers.