Φ 20 in diameter of column reinforcement, are required to choose electroslag pressure welding for welding, in the construction site to intercept of specimens, and then to strength test, select the same type of joint per 200 for a number of testing, test meet the requirements after can begin formal welding work. For the joint bending, transverse cracks, surface burns and other unqualified conditions to remove, and then carry out welding.