Peridynamics modeling of multi-fissure occurrence in the subsiding North China plain
M. Ye, L. Zhu, H. Gong
Capital Normal University, Beijing, China
A. Franceschini, P. Teatini
Dept. of Civil, Environmental and Architectural Engineering,
University of Padova, Padova, Italy
Understanding how excessive groundwater withdrawal and pumping trigger earth fissures at the land surface is
essential for the sustainable management of subsurface resources in subsiding sedimentary basins. This hydroge
ological hazard has become a growing global concern, affecting many countries (e.g., the USA, China, Iran, and
Mexico). Predicting the transition from continuous land subsidence to discontinuous fissure presents a significant
challenge. Here, we propose an effective procedure based on ordinary state-based peridynamics (PD) to simulate
fissure evolution due to groundwater over-pumping. Initially, multi-fissure generation and propagation are ana
lyzed in various hydrogeological configurations, i.e., outcropping bedrock, pre-existing faults offsetting a layered
aquifer system, and bedrock ridges covered by alluvial deposits. Then, the approach is used to investigate fissure
occurrences in the subsiding North China Plain around Beijing, which has been affected by thousands of earth
fissures associated with pre-existing faults aseismically reactivated by excessive exploitation of aquifer systems
over the last decades. PD modeling highlights that wider (up to 0.7 m) and deeper (up to 35 m) fissures develop
with increasing fault dip, aquifer thickness, piezometric decline, and stiffness of surface deposits. The Young's
modulus and pore water pressure exert the most significant control over the scale of earth fissures, the thickness
of the aquifer primarily influences the geometric characteristics of fissures, while the dip angle of the fault zone
governs their spatial distribution pattern.
