Abstract: The present disclosure provides a method and a manufacturing system for preparing adaptive steel-fiber-reinforced precast concrete members, the manufacturing system comprising: a discharging control mechanism, a mixing mechanism, a direction adjustment mechanism for steel fibers, and a 3D printing mechanism, all of which are set in sequence and connected to each other, and both the discharging control mechanism and the direction adjustment mechanism are connected to a same locator; the method comprising: S1: performing a microscopic numerical simulation, obtaining a distribution diagram, thereby constructing a model of the distribution of direction and number of the steel fibers; S2: calculating the mixing ratio, preparing a pre-mixed mortar, and weighing the steel fibers for subsequent use; S3: planning the printing path and comprehensively analyzing the printing path and the model; S4: sending information at each part of the printing path and controlling the distribution at each part of the printing path.

Abstract: A discontinuous deformation measurement method based on infrared and visible light cameras may include: preparing a conductive film and a random speckle pattern on a surface of the conductive film; obtaining a visible image and an infrared image under a loading stage; applying a crack boundary detection to the visible image to obtain an initial coordinate of a micro-crack, determining an range of the micro-crack based on a temperature-rising region from the infrared image and the initial coordinate; setting a position corresponding to the range of the micro-crack in the visible image as a new region of interest; obtaining full-field principal tensile strains by a DIC method, and locating an accurate boundary of the micro-crack based on gradient distribution of the full-field principal tensile strains; analyzing displacement and strain fields around the micro-crack using the DIC method.