The invention discloses a
hybrid-range FBG (
fiber bragg
grating) strain and crack sensor for a concrete material
package. The sensor comprises a pre-cast concrete material
package structure, a spring FBG firmly combined with a micro spring, a pure FBG, a temperature sensor, two penetration grooves, a
temperature sensing area and an armored optical cable. Firstly, the pure FBG and the spring FBG firmly combined with the micro spring are embedded in the two penetration grooves, then, one segment of two groups of the FBG is firmly combined with a die through a high-performance
adhesive, a tension pre-stress is applied on the two groups of the FBG, and then, the other end of each one of the two groups of the FBG is firmly combined, the temperature sensor is embedded in the
package structure, and finally, the armored optical cable is used for connecting the two groups of the led out FBG and the temperature sensor. The
hybrid-range FBG strain and crack sensor is suitable for
structural health monitoring in various concrete structures of
civil engineering, is simple in technology, convenient to arrange, high in accuracy and wide in range, and can monitor internal strain and cracks in overall process of destroying the concrete structure by pulling and pressing.