Model tests on the ground fissures based on the optical
fiber sensing technology

The formation mechanism of ground fissures in southern Jiangsu is complicated, where disasters occur frequently, and they are threats to the living environment. In order to reveal the regular development pattern of ground fissures, a geophysical model is established under the buried-hill condition and the settlement process with the water-drawing variability is simulated by means of a fiber grating sensor. The experimental results show that (1) The non-uniform settlement caused by groundwater over-exploitation is the most direct factor of the development of ground fissures. The more the groundwater level drops and the higher the groundwater extraction rate is, the more obvious the land subsidence is. (2) The location of the buried-hill formation controls the ground settlement, and the areas suffering land subsidence mostly coincide with those with ground fissures. The ground settlement curve and the fissure distribution where the buried hills develop look basically the same. (3) Result of the model experiment corresponds to the evolution pattern of disasters in the studied fissures area. The experimental research with the physical model based on the fiber-optic technology provides new methods and means for ground fissure studies.