Rodrigo A. e Silva , Fady B. Abdelaal , R. Kerry Rowe
{"title":"A 9-year study of the degradation of a HDPE geomembrane liner used in different high pH mining applications","authors":"Rodrigo A. e Silva , Fady B. Abdelaal , R. Kerry Rowe","doi":"10.1016/j.geotexmem.2024.09.012","DOIUrl":"10.1016/j.geotexmem.2024.09.012","url":null,"abstract":"<div><div>The degradation of a HDPE geomembrane in heap leaching environments is evaluated using immersion tests at five temperatures. The incubation solutions had a pH of 9.5, 11.5, and 13.5, relevant to gold and silver pregnant liquor solutions. After 9.3 years, the geomembrane's mechanical properties had reached nominal failure at 95, 85, and 75 °C in all three solutions. It is shown that the pH 13.5 solution had the greatest effect on the antioxidant depletion (Stage I) and polymer degradation (Stage III), but was the least aggressive to initiate the degradation (Stage II) compared to the pH 11.5 and 9.5 solutions. Overall, the time to nominal failure (time to 50% of the initial or specified property value) in pH 13.5 was slightly shorter than the pH 9.5 and 11.5 solutions. Based purely on immsersion tests, the time to nominal failure of this specific geeomembrane at 30<sup>o</sup>C is predicted to be 150 years in the pH 9.5 and 11.5 solutions, and 140 years in the pH 13.5 solution. Assuming a good liner design that limits the tensile strains in the GMB, nominal failure in a composite liner configuration is predicted to exceed 260 years at 30 °C and the expected value could exceed 1000 years at 10 °C.</div></div>","PeriodicalId":55096,"journal":{"name":"Geotextiles and Geomembranes","volume":"53 1","pages":"Pages 230-246"},"PeriodicalIF":4.7,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142428025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Qiang Ma , Chuchen Xi , Chenxi Miao , Yongli Liu , Feng Wu
{"title":"DEM investigation on mechanical behavior of geogrid-sand interface subjected to cyclic direct shear","authors":"Qiang Ma , Chuchen Xi , Chenxi Miao , Yongli Liu , Feng Wu","doi":"10.1016/j.geotexmem.2024.09.014","DOIUrl":"10.1016/j.geotexmem.2024.09.014","url":null,"abstract":"<div><div>The cyclic properties of geosynthetic soil interface are crucial for reinforced soil structures subject to seismic loading. To investigate the mechanical geogrid-sand interface behavior under cyclic shear conditions, a series of numerical simulation cyclic shear tests were conducted using the discrete element method. The results revealed with increasing of shear cycles, dense sand sample gradually shrunk, exhibiting obvious softening characteristics. The vertical displacement of the sample under simulated 10 cyclic shear increases by 0.27 mm, which is 0.41 mm lower than that under 1 cyclic shear. Meanwhile, obvious dilation was observed in the shear band. As the number of cyclic shear increases, the region where the particle rotation occurs does not change significantly, ranging from 75 mm to 125 mm. Higher sample density made it more difficult for particles at geogrid-sand interface to rotate. Under the same number of cycles, denser samples had narrower shear bands, smaller shear strain shifts, and larger shear stiffness. The sand size is 0.5 mm, and the particle displacement concentrated in the 3 mm shear zone. After the completion of cyclic shear, dense sand had little effect on the porosity of the unreinforced sand affected zone, and the porosity after cyclic cycle was close to the initial porosity.</div></div>","PeriodicalId":55096,"journal":{"name":"Geotextiles and Geomembranes","volume":"53 1","pages":"Pages 217-229"},"PeriodicalIF":4.7,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142428024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yu-Xin Gao , Hong-Hu Zhu , Jing-Wen Su , Xu-Yan Ren , Xu-Hui Guo , Hannah Wan-Huan Zhou , Bin Shi
{"title":"Experimental study on deformation and failure mechanism of geogrid-reinforced soil above voids","authors":"Yu-Xin Gao , Hong-Hu Zhu , Jing-Wen Su , Xu-Yan Ren , Xu-Hui Guo , Hannah Wan-Huan Zhou , Bin Shi","doi":"10.1016/j.geotexmem.2024.09.015","DOIUrl":"10.1016/j.geotexmem.2024.09.015","url":null,"abstract":"<div><div>Geosynthetic materials are crucial for reinforcing soil above subterranean voids. However, the complexities of load transfer mechanisms in reinforced structures remain elusive. This study investigates the deformation and failure mechanisms in geogrid-reinforced soil using trapdoor experiments. The particle image velocimetry (PIV) technique was utilized for detailed observation of soil deformation, while fiber optic strain sensing cables were used to monitor tensile strains within geogrids. Results indicate that soil arching redistributes loads across the trapdoor area, effectively transferring loads from subsiding to adjacent stable regions. As trapdoor displacement increases, the initial soil arch collapses, prompting the formation of another stable arch. This cycle of development and failure of soil arch continues until shear bands reach the ground surface. Soil arches are more prone to failure over shallower voids. Strain data reveal that the geogrid's tension varies with the tensile strain and is highest near the void's edges. For shallow voids, the tensioned membrane effect of the geogrid bears more of the overlying soil weight, whereas for deeper voids, soil arching plays a more significant role in load transfer. This study provides important insights into the interaction between soil arching and tensioned membrane effects, offering potential implications for optimizing geosynthetic design.</div></div>","PeriodicalId":55096,"journal":{"name":"Geotextiles and Geomembranes","volume":"53 1","pages":"Pages 203-216"},"PeriodicalIF":4.7,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Multi-scale behaviour of sand-geosynthetic interactions considering particle size effects","authors":"Rizwan Khan, Gali Madhavi Latha","doi":"10.1016/j.geotexmem.2024.09.008","DOIUrl":"10.1016/j.geotexmem.2024.09.008","url":null,"abstract":"<div><div>The continuous evolution of digital imaging and sensing technologies helps in understanding the multi-scale interactions between soils and geosynthetic inclusions in a progressively better way. In this study, advanced techniques like X-ray micro-computed tomography (μCT) and profilometry are used to provide better understanding of the multi-scale interactions between sand and geosynthetic materials in direct shear interface tests. To cover the dilative and non-dilative interfaces and sands of different particle sizes, shear tests were carried out with a woven geotextile and a smooth geomembrane interfacing with three graded sands at different normal stresses. The shear response of different interfaces is analyzed in the light of 3D multi-scale morphology of particles and the roughness of tested geosynthetic surfaces to compare the peak and residual friction angles and shear zone thickness determined using Digital Image Correlation (DIC) technique. The average peak frictional efficiencies for sand-geotextile and sand-geomembrane interfaces are 0.84 and 0.52, respectively. The extent of the shear zone increased with the increase in particle size, with its average thickness ranging from 2.22 to 11.41 times the mean particle size. On a microscopic level, fine sands cause increased shear-induced changes on geomembrane surfaces because of their greater effective contact per unit area.</div></div>","PeriodicalId":55096,"journal":{"name":"Geotextiles and Geomembranes","volume":"53 1","pages":"Pages 169-187"},"PeriodicalIF":4.7,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142320435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Julieta de Goycoechea , Marcos A. Montoro , Daniel A. Glatstein , Karina F. Crespo Andrada , María Gabriela Paraje
{"title":"Biological clogging of geotextiles under discontinuous fermentation scenario","authors":"Julieta de Goycoechea , Marcos A. Montoro , Daniel A. Glatstein , Karina F. Crespo Andrada , María Gabriela Paraje","doi":"10.1016/j.geotexmem.2024.09.013","DOIUrl":"10.1016/j.geotexmem.2024.09.013","url":null,"abstract":"<div><div>This article presents the effect of biological clogging on the hydraulic performance of geotextiles used for the construction of filter and drainage in landfills. Clogging tests were performed on specimens of woven and non-woven geotextiles in a discontinuous fermentation scenario using natural leachate and a nutrient solution. The consequences of biological clogging were assessed through experimental measurements of changes in the cross-plane hydraulic conductivity and the impregnation ratio of different geotextiles specimens at different immersion times. Porosity reduction was then back-calculated from the hydraulic conductivity results using the Kozeny-Carman equation. Additionally, the impact of an antibiotic and antifungal solution on biofilm development was evaluated. It was demonstrated that the cross-plane hydraulic conductivity of geotextile specimens decreases as biomass accumulation per unit area increases with immersion time. The application of an antibiotic and antifungal solution resulted in a porosity recovery of over 90% and a hydraulic conductivity recovery ranging from 78 to 83% for both woven and non-woven geotextiles. These results demonstrate that the clogging was primarily due to biological activity. Despite certain limitations in measurement and definition, the impregnation ratio proved to be a reliable parameter for the evaluation of biological clogging.</div></div>","PeriodicalId":55096,"journal":{"name":"Geotextiles and Geomembranes","volume":"53 1","pages":"Pages 188-202"},"PeriodicalIF":4.7,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"New theoretical solution for soft soil consolidation under vacuum pressure via horizontal drainage enhanced geotextile sheets","authors":"Hao Chen , Jian Chu , Shifan Wu , Wei Guo , Kokpang Lam","doi":"10.1016/j.geotexmem.2024.09.011","DOIUrl":"10.1016/j.geotexmem.2024.09.011","url":null,"abstract":"<div><div>Land reclamation is a major construction activity in Singapore and other Asian countries. When granular fills become scarce, soft materials have to be used for land reclamation. A new land reclamation and soil improvement method using vacuum preloading and horizontal drainage enhanced non-woven geotextile (HDeG) sheets for soft soil consolidation has been proposed to reduce consolidation time and save costs. This paper presents a new theoretical solution for analysing the consolidation process of soil under vacuum pressure via horizontal drainage enhanced geotextile sheets as such a solution is not available yet. To verify the proposed theoretical solution, model tests and finite element analyses (FEA) have also been conducted. The proposed analytical solution agrees well with the results from FEA and the model tests in settlement, average effective stress and degree of consolidation. Thus, this solution could be used for design and analysis for land reclamation with soft materials consolidated using vacuum preloading together with HDeG sheets or other horizontal drainage materials with an adequately high transmissivity. The prediction of the consolidation performance relies on the proper selection of the coefficient of consolidation based on the effective stress history of soil.</div></div>","PeriodicalId":55096,"journal":{"name":"Geotextiles and Geomembranes","volume":"53 1","pages":"Pages 155-168"},"PeriodicalIF":4.7,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142320434","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Implications of single and double liners on the impact of PFOA in landfills on an underlying aquifer","authors":"Farah B. Barakat , R. Kerry Rowe","doi":"10.1016/j.geotexmem.2024.09.009","DOIUrl":"10.1016/j.geotexmem.2024.09.009","url":null,"abstract":"<div><p>The transport of perfluorooctanoic acid (PFOA) through the base of a municipal solid waste landfill lined by a single or double composite liner system underlain by an aquifer is examined. Experiments conducted to obtain permeation coefficients for PFOA (and other PFAS) through HDPE and a GCL at different stress levels are described and the results presented. Experimentally derived interface transmissivity and GCL hydraulic conductivity permeated by a PFAS solution are presented. The experimentally derived parameters for PFOA are then used together with finite element software to model diffusive and diffusive-advective transport of PFOA through holed wrinkles from a landfill. The peak concentrations of PFOA in the modelled aquifer are reported and compared to the maximum allowable drinking water regulations for PFOA in different jurisdictions. A sensitivity analysis is performed to assess the effect of different parameters on the degree of contamination of the aquifer. With no holes in the geomembrane (pure diffusive transport), all regulatory limits are met for both single and double-lined barrier systems. The amount of leakage through holed wrinkles required for PFOA to exceed regulatory limits varies depending on the initial concentration of PFOA and jurisdictional allowable limits. Most results showed that the single composite liner barrier system examined is unlikely to be sufficient to contain PFOA to an acceptable level. The double liner system is more likely to meet regulatory requirements if most of the leakage through the primary is collected.</p></div>","PeriodicalId":55096,"journal":{"name":"Geotextiles and Geomembranes","volume":"53 1","pages":"Pages 140-154"},"PeriodicalIF":4.7,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0266114424001109/pdfft?md5=d470727bc23b223253de6962c115d4a9&pid=1-s2.0-S0266114424001109-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142272932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Penglu Cui , Hongyuan Fang , Fuming Wang , Wengui Cao , Xingyi Zhang , Bocheng Peng , Huixin Li , Shao Yue , Jiachao Zhang
{"title":"Nonlinear creep consolidation of vertical drain-improved soft ground with time-dependent permeable boundary under linearly construction load","authors":"Penglu Cui , Hongyuan Fang , Fuming Wang , Wengui Cao , Xingyi Zhang , Bocheng Peng , Huixin Li , Shao Yue , Jiachao Zhang","doi":"10.1016/j.geotexmem.2024.09.001","DOIUrl":"10.1016/j.geotexmem.2024.09.001","url":null,"abstract":"<div><p>This paper presents an upgraded nonlinear creep consolidation model for VDI soft ground, incorporating a modified UH relation to capture soil creep deformation. Key novelties also include considering linear construction loads, TDP boundary conditions, and Swartzendruber's flow in the small strain consolidation domain. The system was solved using the implicit finite difference method, and numerical solutions were rigorously validated. A parametric analysis reveals that soil viscosity causes abnormal EPP increases under poor drainage conditions during early consolidation. Meanwhile, neglecting the time effect of the secondary consolidation coefficient delayed the overall EPP dissipation process and overestimated the settlement during the middle and late consolidation stages. Furthermore, TDP boundaries, Swartzendruber's flow, and construction processes significantly influence the creep consolidation process but not the final settlement. These findings offer fresh insights into the nonlinear creep consolidation of VDI soft ground, advancing the field.</p></div>","PeriodicalId":55096,"journal":{"name":"Geotextiles and Geomembranes","volume":"53 1","pages":"Pages 121-139"},"PeriodicalIF":4.7,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142245496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Microstructural characteristics and prediction of hydraulic properties of geotextile envelopes via image analysis and pore network modeling","authors":"Hang Li, Jingwei Wu, Chenyao Guo, Haoyu Yang, Zhe Wu, Shuai Qin","doi":"10.1016/j.geotexmem.2024.09.007","DOIUrl":"10.1016/j.geotexmem.2024.09.007","url":null,"abstract":"<div><p>In this study, the microstructural characteristics of geotextile envelopes were investigated via two-dimensional (2D) and three-dimensional (3D) image analysis. A pore network model was constructed to predict the hydraulic properties of the geotextile envelopes. Based on image analysis, the representative domain size of the geotextile envelopes was estimated and was further confirmed by pore network modeling. The results showed that while nonuniformity existed in geotextile envelopes, no noticeable difference was observed in porosity among samples of different sizes. The porosity derived from 3D image analysis was much closer to the theoretical value, with relative error less than 12%. The fibers of the geotextile envelopes were mainly distributed in the in-plane direction and were nearly uniform. The prediction of the permeability coefficient was optimal when hybrid cones and cylinders were considered as the geometric shapes and when the equivalent diameter, inscribed diameter, and total length were used as the geometric properties of the extracted pore network. The capillary pressure curves matched experimental values more closely when using the equivalent diameter for throat diameter. The representative domain size of geotextile envelopes was at least 3500 μm, but no meaningful length could be found along the through-plane direction.</p></div>","PeriodicalId":55096,"journal":{"name":"Geotextiles and Geomembranes","volume":"53 1","pages":"Pages 106-120"},"PeriodicalIF":4.7,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142238323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Characteristics of electro-osmosis consolidation and resistivity evolution in soft clay reinforced with recycled carbon fibers","authors":"Guanyu Chen , Lingwei Zheng , Xunli Zhang , Guoqiang Wu , Cheng Feng , Xudong Zheng , Xinyu Xie","doi":"10.1016/j.geotexmem.2024.09.006","DOIUrl":"10.1016/j.geotexmem.2024.09.006","url":null,"abstract":"<div><p>This study repurposed discarded carbon fiber fabric by mechanically cutting it into short-cut carbon fibers and utilized these fibers in electro-osmosis experiments with varying lengths (5 mm, 10 mm, and 15 mm) and mixing ratios (0.05%, 0.10%, and 0.25%). The results indicated that increasing the length and mixing ratio of recycled carbon fibers effectively reduced the soil resistivity. Furthermore, incorporating an appropriate amount of carbon fibers not only reduced the energy consumption coefficient but also enhanced the electro-osmotic drainage performance. Increasing the length and mixing ratio of carbon fiber also improved the vane shear strength after electro-osmosis consolidation. To promote the application of carbon fiber in electro-osmosis consolidation and to provide support for the development of electro-osmosis consolidation theory and numerical analysis, a resistivity calculation model of carbon fiber-reinforced soil during the electro-osmosis process was developed based on the Ohm's Law and tunneling transmission theory. The model elucidates that during the electro-osmosis process, soil resistivity is influenced by the increase in barrier thickness, which consequently raises the tunneling transmission resistance.</p></div>","PeriodicalId":55096,"journal":{"name":"Geotextiles and Geomembranes","volume":"53 1","pages":"Pages 96-105"},"PeriodicalIF":4.7,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142238322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}