Optimization of Multiple Seepage Piping Parameters to Maximize the Critical Hydraulic Gradient in Bimsoils

Abstract

Seepage failure in the form of piping can strongly influence the stability of block-in-matrix-soils (bimsoils), as well as weaken and affect the performance of bimsoil structures. The multiple-factor evaluation and optimization play a crucial role in controlling the seepage failure in bimsoil. The aim of this study is to improve the ability to control the piping seepage failure in bimsoil. In this work, the response surface method (RSM) was employed to evaluate and optimize the multiple piping parameters to maximize the critical hydraulic gradient (CHG), in combination with experimental modeling based on a self-developed servo-controlled flow-erosion-stress coupled testing system. All of the studied specimens with rock block percentage (RBP) of 30%, 50%, and 70% were produced as a cylindrical shape (50 mm diameter and 100 mm height) by compaction tests. Four uncertain parameters, such as RBP, soil matrix density, confining pressure, and block morphology were used to fit an optimal response of the CHG. The sensitivity analysis reveals the influential order of the studied factors to CHG. It is found that RBP is the most sensitive factor, the CHG decreases with the increase of RBP, and CHG increases with the increase of confining pressure, soil matrix density, and block angularity.

Soil Water Conservation: Dynamics and Impact

“…Moreover, during the secondary tillage, the working tools of the equipment had an erosive effect even when the equipment moves along the contour line. Wang et al [19] contributes to the assessment in the laboratory of the critical hydraulic gradient of bimsoils, concluding that it was mainly sensitive to the percentage of rock blocks.…”

“…Finally, Akramkhanov et al [28] involved local stakeholders in Uzbekistan in a transdisciplinary and participatory approach for innovation development. From a methodological point of view, the contributions involve both field [15,16,18,23,24,29] and laboratory [19] experiments, and modeling [20][21][22], survey [17,27,28] and review [25] studies. The Special Issue includes studies carried out at different spatial scales, from field-to regional-scales.…”

“…Two other papers focus on soil erosion, investigating the specific cases of tillage [18] and piping [19] erosion. In their study, Novák and Hůla [18] used aluminum cubes as tracers to investigate tillage erosion.…”

“…Piping is considered to be the main mechanism leading to the failure of hydraulic structures in bimsoils. Piping seepage failure in bimsoils was investigated by Wang et al [19]. The authors evaluated in the laboratory the critical hydraulic gradient on cylindrical specimens.…”

“…The aim of this Special Issue is to enhance our understanding on conservation strategies for effective and sustainable soil and water management. Contributions focus on: recovery of soil hydraulic properties [14][15][16]; erosion risk [17][18][19]; novel modeling [20][21][22], monitoring [23] and experimental [24] approaches for soil hydraulic characterization; improvement of crop yields [25,26]; water availability and food security [27]; and soil salinity [28]. In the following section we resume all the contributions of this Special Issue.…”