Underpinning pile pre-jacking system and pre-jacking method

The invention discloses an underpinning pile pre-jacking system and a pre-jacking method, and relates to the technical field of civil engineering construction. The pre-jacking system comprises a driving system, a monitoring system, a control system, an underpinning beam and a plurality of groups of underpinning devices; the pre-jacking method comprises the steps that S1, the underpinning pile pre-jacking system is arranged; s2, determining a pre-jacking amount target value and a theoretical load value; s3, in combination with monitoring data of the monitoring system, pre-jacking is conducted on the underpinning pile; and S4, when the settlement value of the underpinned pile is monitored to tend to be stable, pre-jacking is ended. Deformation of the underpinning beam and the underpinning device is dynamically regulated and controlled, the settlement amount of the underpinning beam is monitored in real time through the monitoring system, then the pre-jacking mode is adjusted, the underpinning beam is kept horiz