An efficient transient‐state algorithm for evaluation of leakage through defective cutoff walls

Abstract

Artificial barriers are widely used to prevent leakages. However, due to construction errors during the wall installation, passages with small dimensions may occasionally penetrate through the barrier, undermining its tightness. A three-dimensional discretized algorithm (TDA) is proposed for quantitatively estimating the transient-state discharge rate through defective cutoff walls. By discretizing the wall into a three-dimensional refined mesh grid, the algorithm enables an examination of penetrating passages, an evaluation of defect dimensions, and an estimation of discharge rate through the penetrating passages. A rigorous realization-by-realization comparison between the TDA and the finite element method (FEM) was made, and it was found that the TDA results show strong correlations with the FEM results, but at a remarkably lower (1/10 3-1/10 4) computational cost. The TDA generally gives a discharge rate that is 0.1-1.0 times greater than its FEM counterpart, as the lengthened seepage distance due to random corrugations in the penetrating untreated zone cannot be replicated by the TDA.

A physics-inspired machine learning approach for water-tightness estimation of defective cut-off walls with random construction errors

“…Wu et al [42] adopted a three-dimensional FE model to simulate the groundwater flow field of a deep foundation pit considering the leakage for cut-off walls with wished-in-place defects of deterministic dimensions. Pan et al [21][22][23] proposed an advanced evaluation approach, TDA, to quantitatively evaluate the probabilistic distribution of leakage discharge through cut-off walls with given levels of constructions errors (e.g., random inclination and diameter variation of jet grouted columns). However, such approaches are still not optimal for an instant on-site leakage risk assessment because of the unacceptable computing time.…”

Consolidation Behavior and Compression Prediction Model of Coastal Cement Soil Modified by Nanoclay

“…With the continuous development of economic construction, determining how to carry out engineering construction in coastal soft soil areas has become a problem that many countries need to solve during the development process. For example, due to the current situation of large amounts of coastal areas, China, South Korea, Singapore, and other countries have to carry out engineering construction in these areas to meet their own development needs [1][2][3][4]. Coastal soft soil has the characteristics of high natural water content, large compressibility, and low strength [5], which makes it difficult to meet design requirements and requires cement reinforcement [6,7].…”