Fiber Bragg grating (FBG) sensors hold a great deal of potential for structural monitoring because of their high
sensitivity and exceptional stability for long-term monitoring. FBG sensors have been applied to sense a number of
physical measurands including strain, temperature, pressure etc. These applications are based on the same principle, i.e.
the measurement of Bragg wavelength shift caused by the measurands. The characters and principle of FBG sensors have
been introduced in detail. The relative experiment is done. The results show that FBG sensors have high sensitivity and
long-term stability. It is feasible to use the sensors to the structural health monitoring (SHM). Cement hydration
produces heat, which may provoke important temperature rises in massive structures. Such a high temperature may be a
factor for cracking during the cooling phase. Thus, it is important to be able to calculate and control the heat to be
produced by a given concrete at the mixture-proportioning stage. Theory of heat of hydration is also introduced in this
paper. FBG sensors have been applied successfully in health monitoring for Guomao subway station structure. Compared
with results measured by vibrating wire sensors and computed by finite element method, the monitoring results show
temperature and strains can be accurately measured by FBG sensors. It is convenient to study on heat of hydration of
massive concrete and guide structural design.