Expanded-head anchor rod group anchor test device and test method thereof

The invention relates to an expanded-head anchor rod group anchor test device, which comprises a transparent test box, a plurality of expanded-head anchor rod models arranged in the test box in the horizontal direction, a second servo hydraulic loading device for drawing the plurality of expanded-head anchor rod models, and a first servo hydraulic loading device for vertically pressurizing a soilbody, the box body is filled with a soil body, and the anchoring section model is buried in the middle of the soil body and is tightly attached to the front side wall of the test box; the free sectionmodel of the expanded-head anchor rod is connected with a first displacement meter and a tension and pressure sensor, and the anchoring section model is connected with a second displacement meter; the right ends of the free section models of the multiple expanded-head anchor rods are connected in parallel through a steel plate, and a digital camera is installed on the front side of the test box and electrically connected