{"title":"地聚合物与废铸造砂在稳定石煤粘土路基中的协同作用","authors":"Shriram Marathe , Sowmya N J , Megha Mayuri B G","doi":"10.1016/j.pce.2025.103985","DOIUrl":null,"url":null,"abstract":"<div><div>In the context of road subgrade stabilization, this research explores the innovative application of geopolymer (GP) binder with Waste Foundry Sand (WFS) as chemical stabilizing additives. The aim is to enhance the engineering properties of lithomargic clay (shedi soil) found in the coastal Karnataka region of India. The study draws inspiration from prior studies on lithomargic and lateritic soil in the region, taking into account their unique challenges and vulnerabilities. The investigation focuses on the effectiveness of GP, which synthesizes slag and fly ash as integral binder precursors. The geopolymerization process is facilitated by an aqueous solution of sodium silicate-sodium hydroxide mix, serving as the chemical activating agent. This process involves cementation and chemical alterations within the soil matrix induced by GP, combined with mechanical stabilization using WFS. The study thoroughly examines and elucidates the enhanced compaction properties, Unconfined Compressive Strength (UCS), and California Bearing Ratio (CBR) values. Through Standard Proctor trials, the optimal GP dosage was determined to be with a Na<sub>2</sub>O-to-binder ratio of 3.0 %. Additionally, trials with WFS showed that 15 % of WFS resulted in a 30.65 % improvement in compacted density, along with substantial enhancements in UCS and CBR values. Furthermore, the study extends its insights into low-volume flexible pavement composition design, aligning with Indian standards. It presents a comparative analysis of performance disparities between selected stabilized and un-stabilized lithomargic clay. Durability studies, including prolonged strength (UCS, CBR) tests, wetting-drying repetitions, and freeze-thaw cycles, were conducted to gain confidence in the developed stabilization technique. Micro-structural analysis using scanning electron microscopy (SEM) clearly elucidated the mechanism by which GP-WFS stabilizes lithomargic clay. Overall, the incorporation of furnace slag, fly ash in GP production, and the inclusion of WFS in soil stabilization showcase its sustainable attributes, aligning with global efforts towards eco-friendly developments in pavement construction practices and resource optimization.</div></div>","PeriodicalId":54616,"journal":{"name":"Physics and Chemistry of the Earth","volume":"140 ","pages":"Article 103985"},"PeriodicalIF":3.0000,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Synergy of geopolymer and waste foundry sand in stabilizing lithomargic clay subgrades\",\"authors\":\"Shriram Marathe , Sowmya N J , Megha Mayuri B G\",\"doi\":\"10.1016/j.pce.2025.103985\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>In the context of road subgrade stabilization, this research explores the innovative application of geopolymer (GP) binder with Waste Foundry Sand (WFS) as chemical stabilizing additives. The aim is to enhance the engineering properties of lithomargic clay (shedi soil) found in the coastal Karnataka region of India. The study draws inspiration from prior studies on lithomargic and lateritic soil in the region, taking into account their unique challenges and vulnerabilities. The investigation focuses on the effectiveness of GP, which synthesizes slag and fly ash as integral binder precursors. The geopolymerization process is facilitated by an aqueous solution of sodium silicate-sodium hydroxide mix, serving as the chemical activating agent. This process involves cementation and chemical alterations within the soil matrix induced by GP, combined with mechanical stabilization using WFS. The study thoroughly examines and elucidates the enhanced compaction properties, Unconfined Compressive Strength (UCS), and California Bearing Ratio (CBR) values. Through Standard Proctor trials, the optimal GP dosage was determined to be with a Na<sub>2</sub>O-to-binder ratio of 3.0 %. Additionally, trials with WFS showed that 15 % of WFS resulted in a 30.65 % improvement in compacted density, along with substantial enhancements in UCS and CBR values. Furthermore, the study extends its insights into low-volume flexible pavement composition design, aligning with Indian standards. It presents a comparative analysis of performance disparities between selected stabilized and un-stabilized lithomargic clay. Durability studies, including prolonged strength (UCS, CBR) tests, wetting-drying repetitions, and freeze-thaw cycles, were conducted to gain confidence in the developed stabilization technique. Micro-structural analysis using scanning electron microscopy (SEM) clearly elucidated the mechanism by which GP-WFS stabilizes lithomargic clay. Overall, the incorporation of furnace slag, fly ash in GP production, and the inclusion of WFS in soil stabilization showcase its sustainable attributes, aligning with global efforts towards eco-friendly developments in pavement construction practices and resource optimization.</div></div>\",\"PeriodicalId\":54616,\"journal\":{\"name\":\"Physics and Chemistry of the Earth\",\"volume\":\"140 \",\"pages\":\"Article 103985\"},\"PeriodicalIF\":3.0000,\"publicationDate\":\"2025-06-11\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Physics and Chemistry of the Earth\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S1474706525001354\",\"RegionNum\":3,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"GEOSCIENCES, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physics and Chemistry of the Earth","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1474706525001354","RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
Synergy of geopolymer and waste foundry sand in stabilizing lithomargic clay subgrades
In the context of road subgrade stabilization, this research explores the innovative application of geopolymer (GP) binder with Waste Foundry Sand (WFS) as chemical stabilizing additives. The aim is to enhance the engineering properties of lithomargic clay (shedi soil) found in the coastal Karnataka region of India. The study draws inspiration from prior studies on lithomargic and lateritic soil in the region, taking into account their unique challenges and vulnerabilities. The investigation focuses on the effectiveness of GP, which synthesizes slag and fly ash as integral binder precursors. The geopolymerization process is facilitated by an aqueous solution of sodium silicate-sodium hydroxide mix, serving as the chemical activating agent. This process involves cementation and chemical alterations within the soil matrix induced by GP, combined with mechanical stabilization using WFS. The study thoroughly examines and elucidates the enhanced compaction properties, Unconfined Compressive Strength (UCS), and California Bearing Ratio (CBR) values. Through Standard Proctor trials, the optimal GP dosage was determined to be with a Na2O-to-binder ratio of 3.0 %. Additionally, trials with WFS showed that 15 % of WFS resulted in a 30.65 % improvement in compacted density, along with substantial enhancements in UCS and CBR values. Furthermore, the study extends its insights into low-volume flexible pavement composition design, aligning with Indian standards. It presents a comparative analysis of performance disparities between selected stabilized and un-stabilized lithomargic clay. Durability studies, including prolonged strength (UCS, CBR) tests, wetting-drying repetitions, and freeze-thaw cycles, were conducted to gain confidence in the developed stabilization technique. Micro-structural analysis using scanning electron microscopy (SEM) clearly elucidated the mechanism by which GP-WFS stabilizes lithomargic clay. Overall, the incorporation of furnace slag, fly ash in GP production, and the inclusion of WFS in soil stabilization showcase its sustainable attributes, aligning with global efforts towards eco-friendly developments in pavement construction practices and resource optimization.
期刊介绍:
Physics and Chemistry of the Earth is an international interdisciplinary journal for the rapid publication of collections of refereed communications in separate thematic issues, either stemming from scientific meetings, or, especially compiled for the occasion. There is no restriction on the length of articles published in the journal. Physics and Chemistry of the Earth incorporates the separate Parts A, B and C which existed until the end of 2001.
Please note: the Editors are unable to consider submissions that are not invited or linked to a thematic issue. Please do not submit unsolicited papers.
The journal covers the following subject areas:
-Solid Earth and Geodesy:
(geology, geochemistry, tectonophysics, seismology, volcanology, palaeomagnetism and rock magnetism, electromagnetism and potential fields, marine and environmental geosciences as well as geodesy).
-Hydrology, Oceans and Atmosphere:
(hydrology and water resources research, engineering and management, oceanography and oceanic chemistry, shelf, sea, lake and river sciences, meteorology and atmospheric sciences incl. chemistry as well as climatology and glaciology).
-Solar-Terrestrial and Planetary Science:
(solar, heliospheric and solar-planetary sciences, geology, geophysics and atmospheric sciences of planets, satellites and small bodies as well as cosmochemistry and exobiology).