Carbon fiber reinforced plastic electrofusion fitting and a self-monitoring method of strain

A carbon fiber reinforced plastic electrofusion fitting with self-monitoring function of strain, the electrofusion fitting comprising an electrofusion fitting body embedded with a resistance heating wire, with two terminals being arranged on the electrofusion fitting body and connected to the two ends of the resistance heating wire respectively, wherein the electrofusion fitting body is made of a thermoplastic filled with short carbon fiber to improve an electrical conductivity of an electrofusion fitting body material;

• the carbon fiber has a diameter of 7˜10 μm and a length of 1˜5 mm and a weight fraction of the short carbon fiber being 12˜15 wt % for a reinforced plastic of the electrofusion fitting body to improve gauge factor while enhancing mechanical enhancement, a conductive silver glue layer on a surface of the electrofusion fitting body to reduce a contact resistance between electrodes and the electrofusion fitting body, and at least one pair of electrodes being set on a surface of the electrofusion fitting body for monitoring a resistance change of the electrofusion fitting body material,
• wherein the electrodes are set between the resistance heating wire, the electrodes being set circumferentially along the electrofusion fitting to monitor an axial strain of the fitting, or being set along an axial direction of the electrofusion fitting to monitor a circumferential strain of the fitting;
• also, the electrodes being set at an angle of less than 45° to the circumferential or axial direction of the electrofusion fitting, to monitor the circumferential and axial strain of the fitting.