Pre-embedded and prefabricated magnetic attraction end guiding type building crack repairing device and method based on magnetic force

The invention provides a pre-embedded and prefabricated magnetic attraction end guiding type building crack repairing device and a method based on magnetic force. The device comprises a steel bar pre-embedded in a reinforced concrete beam body; the steel bar is wound with a tinned copper wire; the tinned copper wire penetrates through a reserved wire interface pre-formed in the reinforced concrete beam body; the tinned copper wire is connected with an electromagnetic induction device used for providing current; a guide hole is formed in the position, where a crack easily occurs, of the reinforced concrete beam body; and the guide hole is connected with a high-pressure jet grouting machine through a grouting pipe, and then magnetic mortar is injected into the crack. The magnetic mortar is injected into a required position under the guide adsorption of different magnetic attraction ends, so that the sufficient grouting effect is achieved, and the crack repairing and filling rate is increased. According to the p