30m缺陷预制箱梁
30m-defected precast box beam
60m预制混凝土箱梁
60 m precast concrete box girder
GRC预制薄壁管
GRC precast thin-wall tube
MTT法预制检测板
MTT prepare to make to examine the plank
T梁预制
T girder prefabrication
prefabricating of T-shaped beams
T-beam prefabrication
半圆体预制
Prefabrication of Semi-circular Concrete Units