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Aziz A, Soroush A, Fattahi SM, Imam SMR, Ghahremani M. Chemical improvement of soluble rocks: Foundation of Mosul Dam as case study. Sci Rep 2024; 14:14103. [PMID: 38890376 PMCID: PMC11189501 DOI: 10.1038/s41598-024-64593-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Accepted: 06/11/2024] [Indexed: 06/20/2024] Open
Abstract
The dissolution of soluble rocks (gypsum/anhydrite) beneath the Mosul Dam by water seepage has been observed upon the initial impoundment; consequently, several sinkholes have been manifested in the vicinity of the dam site. Traditional grouting has been envisaged as a potential remedy; however this measure has not eradicated the problem. The main purpose of this study is to overcome the solubility of the gypsum/anhydrite rocks using chemical grouts. Rock samples were acquired from the Fatha Formation outcrop and problematic layers of brecciated gypsum situated at varying depths beneath the Mosul Dam. Two commercially available liquid polymers, polyurethane (PU) and a mixture of acrylic and cement (ARC) were used to investigate their sealing performance in halting of the solubility of the rocks (gypsum/anhydrite). To simulate the dissolution phenomenon under the influence of artificial hydraulic pressure of the dam and the water flow in its abutments, two distinct laboratory models were devised. The outcomes from the experimental study on both untreated and treated samples revealed that the acrylic-cement composite (ARC) and polyurethane (PU) are influential polymers in halting the solubility of the gypsum rock samples under both factors of water pressure and high-velocity water flow.
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Affiliation(s)
- Aram Aziz
- Department of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, Iran
- Faculty of Engineering, Koya University, Erbil, KRI, Iraq
| | - Abbas Soroush
- Department of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, Iran.
| | - Seyed Mohammad Fattahi
- Department of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, Iran
| | - Seyed Mohammad Reza Imam
- Department of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, Iran
| | - Mehrdad Ghahremani
- Department of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, Iran
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2
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Ma Q, Chen J, Li W, Wu N. Studying the Properties of Chromium-Contaminated Soil Solidified by Polyurethane. Polymers (Basel) 2023; 15:polym15092118. [PMID: 37177264 PMCID: PMC10181012 DOI: 10.3390/polym15092118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 04/25/2023] [Accepted: 04/25/2023] [Indexed: 05/15/2023] Open
Abstract
The solidification of chromium-contaminated soil using polyurethane (PU) was systematically investigated. The unconfined compression test was conducted to investigate the effects of the curing time, PU dosage and the content of chromium ions on the unconfined compressive strength (UCS) of chromium-contaminated soil. The effect of the PU dosage on the pore structure was investigated using nuclear magnetic resonance (NMR) and scanning electron microscopy (SEM), and the mechanism of strength change was revealed by combining the strength law with the pore structure development law. In addition, the ability of the PU to solidify the chromium-contaminated soil was studied by the toxicity characteristic leaching procedure (TCLP). According to the above test results, the UCS and the ability of the PU to solidify the chromium ions increased with the increase in curing time. The NMR tests showed that with the increase in PU dosage, the porosity decreased and the soil became more compact, hence increasing the strength. When the chromium ion content was 2000 mg/kg and the PU dosage was 8%, the strength of the sample was 0.37 MPa after curing for 24 h, which met the requirement of 0.35 MPa set by the U.S. Environmental Protection Agency. Consequently, PU is a solidification agent with high-early strength.
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Affiliation(s)
- Qiang Ma
- Innovation Demonstration Base of Ecological Environment Geotechnical and Ecological Restoration of Rivers and Lakes, School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430068, China
| | - Junjie Chen
- Innovation Demonstration Base of Ecological Environment Geotechnical and Ecological Restoration of Rivers and Lakes, School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430068, China
| | - Wentao Li
- Innovation Demonstration Base of Ecological Environment Geotechnical and Ecological Restoration of Rivers and Lakes, School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430068, China
| | - Nianze Wu
- Innovation Demonstration Base of Ecological Environment Geotechnical and Ecological Restoration of Rivers and Lakes, School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430068, China
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Lu H, Dun C, Jariwala H, Wang R, Cui P, Zhang H, Dai Q, Yang S, Zhang H. Improvement of bio-based polyurethane and its optimal application in controlled release fertilizer. J Control Release 2022; 350:748-760. [PMID: 36030990 DOI: 10.1016/j.jconrel.2022.08.039] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 08/20/2022] [Accepted: 08/21/2022] [Indexed: 11/28/2022]
Abstract
In the past decades, polyurethane has emerged as a new material that has been widely developed and applied in coated controlled release fertilizers (CRFs). Particularly in recent years, the excessive consumption of petroleum resources and increasing demand for sustainable development have resulted in considerable interest in bio-based polyurethane coated controlled-release fertilizers. This review article focuses on the application and progress of environmentally friendly bio-based materials in the polyurethane-coated CRF industry. We also explore prospects for the green and sustainable development of coated CRFs. Using animal and plant oils, starch, lignin, and cellulose as raw materials, polyols can be produced by physical, chemical, and biological means to replace petroleum-based materials and polyurethane film coating for CRFs can be prepared. Various modifications can also improve the hydrophobicity and degradability of polyurethane film. A growing body of research on bio-based polyurethane has revealed its great potential in the production and application of coated CRFs. The purpose of this review is to highlight the practicality of bio-based materials in the application of polyurethane-coated CRFs and to clarify their current limitations.
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Affiliation(s)
- Hao Lu
- Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province, Yangzhou University, Yangzhou, Jiangsu 225009, China; Key Laboratory of Saline-alkali Soil Improvement and Utilization (Coastal Saline-alkali Lands), Ministry of Agriculture and Rural Affairs, P.R. China, Yangzhou University, Yangzhou, Jiangsu, China
| | - Canping Dun
- Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province, Yangzhou University, Yangzhou, Jiangsu 225009, China
| | - Hiral Jariwala
- School of Engineering, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
| | - Rui Wang
- Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province, Yangzhou University, Yangzhou, Jiangsu 225009, China
| | - Peiyuan Cui
- Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province, Yangzhou University, Yangzhou, Jiangsu 225009, China
| | - Haipeng Zhang
- Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province, Yangzhou University, Yangzhou, Jiangsu 225009, China
| | - Qigen Dai
- Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province, Yangzhou University, Yangzhou, Jiangsu 225009, China; Key Laboratory of Saline-alkali Soil Improvement and Utilization (Coastal Saline-alkali Lands), Ministry of Agriculture and Rural Affairs, P.R. China, Yangzhou University, Yangzhou, Jiangsu, China
| | - Shuo Yang
- Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province, Yangzhou University, Yangzhou, Jiangsu 225009, China
| | - Hongcheng Zhang
- Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province, Yangzhou University, Yangzhou, Jiangsu 225009, China.
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Mechanism confirmation of organofunctional silanes modified sodium silicate/polyurethane composites for remarkably enhanced mechanical properties. Sci Rep 2021; 11:9407. [PMID: 33931695 PMCID: PMC8087689 DOI: 10.1038/s41598-021-88893-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 04/19/2021] [Indexed: 11/21/2022] Open
Abstract
Hybrid reinforced sodium silicate/polyurethane (SS/PU) composites mainly derived from low-cost SS and polyisocyanate are produced by a one-step method based on the addition of 3-chloropropyltrimethoxysilane (CTS). The wettability of SS on PU substrate surface is much improved as CTS content increases from 0.0 to 3.5 wt%. Furthermore, with 2.5 wt% of CTS optimal addition, the fracture surface morphology and elemental composition of the resulting SS/PU composites are characterized, as well as mechanical properties, chemical structure and thermal properties. The results indicate that the CTS forms multiple physical and chemical interactions with the SS/PU composites to induce an optimized organic–inorganic hybrid network structure thus achieving simultaneous improvement of compressive strength, flexural strength, flexural modulus and fracture toughness of the SS/PU composites, with the improvement of 12.9%, 6.6%, 17.5% and 9.7%, respectively. Moreover, a reasonable mechanism explanation for CTS modified SS/PU composites is confirmed. Additionally, the high interface areas of the organic–inorganic phase and the active crosslinking effect of the CTS are the main factors to determine the curing process of the SS/PU composites.
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Numerical simulation with hardening soil model parameters of marine clay obtained from conventional tests. SN APPLIED SCIENCES 2021. [DOI: 10.1007/s42452-020-04115-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
AbstractOver the last decades, numerical modelling has gained practical importance in geotechnical engineering as a valuable tool for predicting geotechnical problems. An accurate prediction of ground deformation is achieved if models that account for the pre-failure behaviour of soil are used. In this paper, laboratory results of the consolidated drain (CD) triaxial compression tests and one-dimensional consolidation tests of marine clay were used to determine the hardening soil model (HSM) parameter for use in Plaxis 3D analyses. The parameters investigated for the HSM were stiffness, strength and advanced parameters. The stiffness parameters were secant stiffness in CD triaxial compression test ($$E_{50}^{\text{ref}}$$
E
50
ref
), tangent stiffness for primary oedometer loading test $$(E_{\text{oed}}^{\text{ref}} )$$
(
E
oed
ref
)
, unloading/reloading stiffness $$(E_{\text{ur}}^{\text{ref}}$$
(
E
ur
ref
) and power for the stress-level dependency of stiffness (m). The strength parameters were effective cohesion ($$c_{\text{ref}}^{\text{'}}$$
c
ref
'
), effective angle of internal friction ($$\phi^{\text{'}}$$
ϕ
'
) and angle of dilatancy ($$\psi^{\text{'}}$$
ψ
'
). The advanced parameters were Poisson’s ratio for unloading–reloading (ν) and K0-value for normal consolidation $$\left( {K_{\circ}^{\text{nc}} } \right)$$
K
∘
nc
. Furthermore, Plaxis 3D was used to simulate the laboratory results to verify the effectiveness of this study. The results revealed that the stiffness parameters $$E_{50}^{\text{ref}} , E_{\text{oed}}^{\text{ref}} , E_{\text{ur}}^{\text{ref}}$$
E
50
ref
,
E
oed
ref
,
E
ur
ref
and m are equal to 3.4 MPa, 3.6 MPa, 12 MPa and 0.7, respectively, and that the strength parameters $$c_{\text{ref}}^{\text{'}}$$
c
ref
'
, $$\phi^{\text{'}}$$
ϕ
'
, $$\psi^{\text{'}}$$
ψ
'
and $$K_{\circ}^{\text{nc}}$$
K
∘
nc
are equal to 33 kPa, 17.51°, 1.6° and 0.7, respectively. A final comparison of the laboratory results with the numerical results revealed that they were in accordance, which proved the efficacy of the study.
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