The utility model relates to a R angular region ultrasonic phased array detects and uses test block in strand anchor cup, including test block and long cross bore (2) of setting at R angle area (1), test block and strand anchor cup R angle area (1) material, specification are the same, R angle area (1) provides R angle circular arc (3), long cross bore (2) set up at R angle circular arc (3) top apart from the certain degree of depth department of surface, arrange along the radial extension line direction equidistance of R angle circular arc (3) the centre of a circle to R angle circular arc (3) top long cross bore (2), long cross bore (2) are cylindrically. The utility model discloses fundamentally has solved strand anchor cup R angle area ultrasonic phased array and has detected a no reference block difficult problem, confirms the sensitivity of ultrasonic phased array detection and the position of confirming the defect, adopt material, the specification the same with strand anchor cup to complete, and design and operation is simple, strand 0.