Storage Earth Dam Failure due to Liquefaction Caused by Earthquakes
Authors: Kiraa Mohamed Soliman , Zeidan Bakenaz , Nasr Ahmed Mohamed , Heza Yehiaa Barakat 
Published: November 2023

Aims:

We are researching causes and criteria for the liquefaction dam failure by analyzing the safety of the dam under static and dynamic loads against shear failure using the finite element technique, which is used to simulate stability assessment for selected earth dams under different loading conditions.

Background:

Storage Massive earth dams are vulnerable to collapse during earthquakes, which can have severe effects ranging from direct human casualties to indirect economic losses. How seismically fragile earth dams are and what issues may arise from a failure depend on how they respond to earthquakes. Slope failure, piping, displacement, and/or settlement are examples of seismic responses that are caused by weak soil and/or the liquefaction of loose sands. Earth dam failure can be caused by a variety of factors, including seepage through the dam body, hydraulic issues, structural instability, and liquefaction failure brought on by earthquakes.

Objective:

The objective of this study is to find a way to design of earth-fill dams.

Methods:

The finite element method is a numerical solution. This method is based on a grid pattern (not necessarily rectangular) which divides the flow region into discrete elements and provides N equations with N unknowns. Material properties, such as permeability, are specified for each element, and boundary conditions (heads and flow rates) are set. The finite element method has several advantages over the finite difference method for more complex seepage problems.

Results:

The Lower San Fernando Dam is dangerous under dynamic loads, and the F.O.S. values for the upstream and downstream directions are 0.264 and 0.183, respectively. 1350 m2 is the Lower San Fernando Dam's liquefaction area. 40.67% of the Lower San Fernando Dam's overall foundation area is represented by that figure. Tapar (India) dam is hazardous due to slope failure under dynamic loads, and the F.O.S. values for the upstream and downstream directions are 0.5 and 0.109, respectively. Tapar Dam in India has a liquefaction area of 457 m2. This amount equals 52.33 percent of the Tapar (India) dam's entire foundation area. The slope failure under dynamic loads and the F.O.S. values of 0.313 and 0.548 for the slopes of the river upstream and downstream of Fatehgadh dam (India), respectively, lead to the conclusion that it is dangerous. 333.5 m2 is the size of the liquefaction area of the Fatehgadh dam in India. The foundation area of the Fatehgadh (India) dam as a whole is represented by that figure at 78.75%. Saluda Dam in Columbia is an unsafe slope failure under dynamic loads, and the F.O.S. values for the upstream and downstream directions are 0.102 and 0.101. Saluda Dam in Columbia has a 32095 m2 liquefaction area. This value represents 32.96% of the Saluda Dam's total foundation area (Columbia).

Conclusion:

Conclusions state that 32.96% of the minimum liquefaction zone area is what causes liquefaction failure. Under the effect of seismic stresses, a safe design standard for storage earth dams is produced. The evaluation must also take into account the specifications for safety limitations based on global norms, regulations, and codes. examining the dam safety requirements for dynamic loads.