Due to earthquake effects, buildings often experience large strains, leading to progressive collapses. Monitoring and
assessing the large strain condition of critical buildings is of paramount importance to post-earthquake responses and
evacuations in earthquake-prone regions. However, few monitoring system can work under such harsh environments.
For their unique attributes such as compactness, immunity to electromagnetic interference and capability integrated
within various types of structures and materials, optical fiber sensors are especially attractive for quasi-distributed
strain sensing purposes in harsh environments. Nevertheless, the dynamic range of strain measurements of an optical
sensor is limited by the elasticity of the optical fiber. In this paper, a quasi-distributed optical fiber sensor network
based on extrinsic Fabry-Perot interferometer (EFPI) and long-period fiber grating (LPFG) sensors for both large strain
and high temperature measurements has been developed. The sensor network combined several inline EFPIs and
LPFGs by various couplers. Each EFPI sensor in the sensor network system has the capacity of large strain
measurement up to 12% and each LPFG sensor here has a temperature measurement range of up to 700°C. To obtain
strain and temperature information for multiple locations more efficiently, a hybrid LPFG/EFPI optical fiber sensor
based sensor network system has been studied in this paper. Experimental results demonstrate that the proposed quasi-distributed
optical fiber sensor network system is capable for both large strain and high temperature measurements.
Therefore, the proposed optical fiber sensor network system can be applied to monitor the quasi-distributed strain of
civil infrastructure in harsh environments.