Special prism clamping seat for existing track measurement

The utility model discloses a special prism clamping seat for existing track measurement. The special prism clamping seat comprises an inverted U-shaped clamping groove matched with the shape of the cross section of a steel rail, the radian of the left inner edge corner of the inverted-U-shaped clamping groove is consistent with that of the inner side corner of the top face of the steel rail, theright inner edge corner of the inverted-U-shaped clamping groove is a right angle, and the width of the inverted-U-shaped clamping groove is larger than that of the top face of the steel rail. A connecting screw hole is formed in the top of the inverted-U-shaped clamping groove, and a prism bar is vertically and upwards connected into the connecting screw hole in a screwed mode. And a telescopic device for adjusting the tightness is arranged on the right side wall of the inverted U-shaped clamping groove. The device has the advantages that the device is specially designed for track measurement, the tedious process tha