The water content of soils is frequently needed, and its reference value is currently obtained by conventional convection ovens. Infrared (IR) ovens appear to be overlooked by the geotechnical community even though they allow for precise control over temperature, much faster heat transfer, and much better energy efficiency resulting from its inherent low thermal inertia. The European Commission’s climate action enacts several policies for greener, sustainable, and energy efficient solutions. The objective of this study is to investigate the usability and efficiency of IR ovens as the permanent replacement for conventional ovens for supporting a greener and sustainable environment. Particular emphasis is given to precision and energy efficiency through experimental comparisons. The results suggest that IR ovens offer 70 % implied energy savings over conventional ovens while resulting in comparable precision. It is, therefore, proposed to adopt IR ovens as the new and preferred standard for water content determination and to abandon conventional ovens after a transition period.
{"title":"Infrared Drying for Water Content Measurements of Soils","authors":"Sami Arsoy","doi":"10.1520/gtj20220122","DOIUrl":"https://doi.org/10.1520/gtj20220122","url":null,"abstract":"The water content of soils is frequently needed, and its reference value is currently obtained by conventional convection ovens. Infrared (IR) ovens appear to be overlooked by the geotechnical community even though they allow for precise control over temperature, much faster heat transfer, and much better energy efficiency resulting from its inherent low thermal inertia. The European Commission’s climate action enacts several policies for greener, sustainable, and energy efficient solutions. The objective of this study is to investigate the usability and efficiency of IR ovens as the permanent replacement for conventional ovens for supporting a greener and sustainable environment. Particular emphasis is given to precision and energy efficiency through experimental comparisons. The results suggest that IR ovens offer 70 % implied energy savings over conventional ovens while resulting in comparable precision. It is, therefore, proposed to adopt IR ovens as the new and preferred standard for water content determination and to abandon conventional ovens after a transition period.","PeriodicalId":55099,"journal":{"name":"Geotechnical Testing Journal","volume":"31 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135513826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aysegul Bayin Sariahmetoglu, Mustafa Hatipoglu, Asli Y. Dayioglu
Highway drainage systems are designed to remove surface water and groundwater without deteriorating the road structure; hence, their durability is crucial to sustain the performance of highways. Filtration performance of a drainage system consisting of aggregate and geotextiles is one key parameter that needs to be carefully assessed so that clogging of the system does not result in failure. Substituting the natural aggregate in drainage systems with recycled materials would result in preservation of natural resources and employment of stockpiled recycled material, creating a mutually beneficial solution. In this study, the long-term filtration performance of three different recycled materials from different industries (i.e., two steel slag, recycled asphalt pavement, recycled concrete aggregate) has been investigated when used as filter material in drainage systems. Furthermore, two natural aggregate materials as control soils were used to compare the performance of recycled materials. A nonwoven geotextile with a low apparent opening size that represents the least favorable scenario in terms of clogging was selected as the filtration media. Long-term filtration experiments were carried out in the modified gradient ratio test setup and the hydraulic gradient ratio (GR) along with the permeability ratio (KR) were determined under different hydraulic gradients to evaluate the clogging performance. The results indicate that even under the most undesirable conditions, recycled materials exhibit a satisfactory filtration performance compared with natural aggregates, and they can be employed as aggregate material in highway drainage systems.
{"title":"Comparative Evaluation of the Long-Term Filtration Performance of Recycled Materials in Highway Drainage Systems","authors":"Aysegul Bayin Sariahmetoglu, Mustafa Hatipoglu, Asli Y. Dayioglu","doi":"10.1520/gtj20220279","DOIUrl":"https://doi.org/10.1520/gtj20220279","url":null,"abstract":"Highway drainage systems are designed to remove surface water and groundwater without deteriorating the road structure; hence, their durability is crucial to sustain the performance of highways. Filtration performance of a drainage system consisting of aggregate and geotextiles is one key parameter that needs to be carefully assessed so that clogging of the system does not result in failure. Substituting the natural aggregate in drainage systems with recycled materials would result in preservation of natural resources and employment of stockpiled recycled material, creating a mutually beneficial solution. In this study, the long-term filtration performance of three different recycled materials from different industries (i.e., two steel slag, recycled asphalt pavement, recycled concrete aggregate) has been investigated when used as filter material in drainage systems. Furthermore, two natural aggregate materials as control soils were used to compare the performance of recycled materials. A nonwoven geotextile with a low apparent opening size that represents the least favorable scenario in terms of clogging was selected as the filtration media. Long-term filtration experiments were carried out in the modified gradient ratio test setup and the hydraulic gradient ratio (GR) along with the permeability ratio (KR) were determined under different hydraulic gradients to evaluate the clogging performance. The results indicate that even under the most undesirable conditions, recycled materials exhibit a satisfactory filtration performance compared with natural aggregates, and they can be employed as aggregate material in highway drainage systems.","PeriodicalId":55099,"journal":{"name":"Geotechnical Testing Journal","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135805064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yashay Narainsamy, Schalk Willem Jacobsz, Ruan Andrew Murison, Nicolaas Johannes Vermeulen
Depending on the stress state, mine tailings are generally accepted to be susceptible to static liquefaction. A common method to assess the in situ stress state of tailings in relation to static liquefaction susceptibility involves the use of the state parameter. Because most tailings materials are normally consolidated (NC), this type of assessment requires knowledge about the normal consolidation line (NCL). It has been shown experimentally that the uniqueness of the NCL is vastly different for fine-grained and coarse-grained soils, with clays usually exhibiting a unique NCL and clean sands exhibiting an infinite number of parallel NCLs. Gold tailings, a sandy silt, fall between clays and clean sands, and there are limited experimental data regarding their compression behavior over a range of initial void ratios. This lack of data results in inconsistent interpretation of the uniqueness of the NCL for gold tailings in the industry. This can influence the results of designs and safety evaluations of tailings dams. In this study, a number of oedometer tests were conducted on gold tailings sourced from an active tailings dam in South Africa. Several specimens were prepared at various initial densities and were consolidated in small increments to a high effective stress. The oedometer tests were supplemented with triaxial compression tests, from which a unique critical state line was identified. Across the oedometer and triaxial tests, it was found that the behavior of the NC and overconsolidated samples was consistent with that typically observed for fine-grained soils. Therefore, for practical purposes, it appears that the gold tailings tested can be viewed in a framework with a unique NCL. No significant influence of particle crushing was noted.
{"title":"Uniqueness of the Normal Consolidation Line for Gold Tailings","authors":"Yashay Narainsamy, Schalk Willem Jacobsz, Ruan Andrew Murison, Nicolaas Johannes Vermeulen","doi":"10.1520/gtj20230325","DOIUrl":"https://doi.org/10.1520/gtj20230325","url":null,"abstract":"Depending on the stress state, mine tailings are generally accepted to be susceptible to static liquefaction. A common method to assess the in situ stress state of tailings in relation to static liquefaction susceptibility involves the use of the state parameter. Because most tailings materials are normally consolidated (NC), this type of assessment requires knowledge about the normal consolidation line (NCL). It has been shown experimentally that the uniqueness of the NCL is vastly different for fine-grained and coarse-grained soils, with clays usually exhibiting a unique NCL and clean sands exhibiting an infinite number of parallel NCLs. Gold tailings, a sandy silt, fall between clays and clean sands, and there are limited experimental data regarding their compression behavior over a range of initial void ratios. This lack of data results in inconsistent interpretation of the uniqueness of the NCL for gold tailings in the industry. This can influence the results of designs and safety evaluations of tailings dams. In this study, a number of oedometer tests were conducted on gold tailings sourced from an active tailings dam in South Africa. Several specimens were prepared at various initial densities and were consolidated in small increments to a high effective stress. The oedometer tests were supplemented with triaxial compression tests, from which a unique critical state line was identified. Across the oedometer and triaxial tests, it was found that the behavior of the NC and overconsolidated samples was consistent with that typically observed for fine-grained soils. Therefore, for practical purposes, it appears that the gold tailings tested can be viewed in a framework with a unique NCL. No significant influence of particle crushing was noted.","PeriodicalId":55099,"journal":{"name":"Geotechnical Testing Journal","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135302605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fausto Molina-Gómez, António Viana da Fonseca, Cristiana Ferreira, Bernardo Caicedo
{"title":"Experimental Wave-Based Assessment of Liquefaction Resistance for Different Degrees of Saturation","authors":"Fausto Molina-Gómez, António Viana da Fonseca, Cristiana Ferreira, Bernardo Caicedo","doi":"10.1520/gtj20230299","DOIUrl":"https://doi.org/10.1520/gtj20230299","url":null,"abstract":"","PeriodicalId":55099,"journal":{"name":"Geotechnical Testing Journal","volume":"199 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135648211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Buddhima Indraratna, Chathuri M. K. Arachchige, Cholachat Rujikiatkamjorn, Ana Heitor, Yujie Qi
{"title":"Utilization of Granular Wastes in Transportation Infrastructure","authors":"Buddhima Indraratna, Chathuri M. K. Arachchige, Cholachat Rujikiatkamjorn, Ana Heitor, Yujie Qi","doi":"10.1520/gtj20220233","DOIUrl":"https://doi.org/10.1520/gtj20220233","url":null,"abstract":"","PeriodicalId":55099,"journal":{"name":"Geotechnical Testing Journal","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135790591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
María Juliana Chaparro López, Juan-Pablo Castillo-Betancourt, Miguel Cabrera, Bernardo Caicedo, Pierre Delage, Philippe Lognonné, Bruce Banerdt
The dynamic properties of loose sands under low stresses are an unexplored topic in soil dynamics because these soil conditions are uncommon in most geotechnical structures on Earth. However, low densities and low-stress conditions prevail on other planets, like, for instance, the surface of Mars, for which particular attention is presently given through the InSight NASA mission. This work presents a new procedure for measuring the dynamic properties of loose sand under low stress by using the dynamical mechanical analysis (DMA) tester, a technique commonly used in asphalt engineering but not in geotechnical engineering. Compared to traditional geotechnical methods (resonant column and cyclic triaxial tests), DMA investigates a broader range of strains using a single apparatus. In this work, we assess the dynamical properties of loose fine sand Dr ≈ 0.2, considered a possible Mars regolith analog, by varying the input strain from γ = 10−6 to γ = 10−2 while applying confining pressures from σ3 = 3 kPa to σ3 = 30 kPa. The results validate the proposed procedure, showing an increment of the shear modulus as the confining pressure increases. Furthermore, they highlight DMA’s advantages for studying the dynamic properties of granular soils under low stress and strain.
{"title":"Dynamic Mechanical Analysis Test for Evaluating Loose Sands on a Wide Strain Range—Application to the InSight Mission on Mars","authors":"María Juliana Chaparro López, Juan-Pablo Castillo-Betancourt, Miguel Cabrera, Bernardo Caicedo, Pierre Delage, Philippe Lognonné, Bruce Banerdt","doi":"10.1520/gtj20230381","DOIUrl":"https://doi.org/10.1520/gtj20230381","url":null,"abstract":"The dynamic properties of loose sands under low stresses are an unexplored topic in soil dynamics because these soil conditions are uncommon in most geotechnical structures on Earth. However, low densities and low-stress conditions prevail on other planets, like, for instance, the surface of Mars, for which particular attention is presently given through the InSight NASA mission. This work presents a new procedure for measuring the dynamic properties of loose sand under low stress by using the dynamical mechanical analysis (DMA) tester, a technique commonly used in asphalt engineering but not in geotechnical engineering. Compared to traditional geotechnical methods (resonant column and cyclic triaxial tests), DMA investigates a broader range of strains using a single apparatus. In this work, we assess the dynamical properties of loose fine sand Dr ≈ 0.2, considered a possible Mars regolith analog, by varying the input strain from γ = 10−6 to γ = 10−2 while applying confining pressures from σ3 = 3 kPa to σ3 = 30 kPa. The results validate the proposed procedure, showing an increment of the shear modulus as the confining pressure increases. Furthermore, they highlight DMA’s advantages for studying the dynamic properties of granular soils under low stress and strain.","PeriodicalId":55099,"journal":{"name":"Geotechnical Testing Journal","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136263671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. P. Singh, K. Seshagiri Rao, Ramanathan Ayothiraman
This paper presents the findings from a model experimental setup designed and fabricated for conducting single gravity (1-g) model experiments on model aluminum instrumented piles embedded in synthetic rock subjected to both independent vertical–compressive and lateral loading and combined vertical–compressive and lateral loading. Synthetic rock was prepared based on a mix design that can simulate the strength and modulus of soft rocks. Model tests were carried out on single piles of different socketing lengths (L/D ratios: 6, 9, and 12). Combined loading tests were done such that the resultant of the vertical–compressive and lateral loads was at constant inclinations (30° and 60°). Piles with smooth and rough surfaces were simulated for examining the effect of the pile–rock roughness profile. The vertical load–settlement and the lateral load–deflection response were measured from the tests. The bending behavior of piles under both independent and combined loading was also measured. The deflection profile of the rock-socketed pile was obtained by tracing the tested/failed piles after extracting them. The axial and lateral resistance of the rock-socketed piles are interpreted and discussed. It is observed that the rock-socketed piles behave in a distinctly different manner under combined loading compared with independent loading.
{"title":"Model Testing of Rock-Socketed Piles under Combined Vertical–Lateral Loading","authors":"A. P. Singh, K. Seshagiri Rao, Ramanathan Ayothiraman","doi":"10.1520/gtj20220173","DOIUrl":"https://doi.org/10.1520/gtj20220173","url":null,"abstract":"This paper presents the findings from a model experimental setup designed and fabricated for conducting single gravity (1-g) model experiments on model aluminum instrumented piles embedded in synthetic rock subjected to both independent vertical–compressive and lateral loading and combined vertical–compressive and lateral loading. Synthetic rock was prepared based on a mix design that can simulate the strength and modulus of soft rocks. Model tests were carried out on single piles of different socketing lengths (L/D ratios: 6, 9, and 12). Combined loading tests were done such that the resultant of the vertical–compressive and lateral loads was at constant inclinations (30° and 60°). Piles with smooth and rough surfaces were simulated for examining the effect of the pile–rock roughness profile. The vertical load–settlement and the lateral load–deflection response were measured from the tests. The bending behavior of piles under both independent and combined loading was also measured. The deflection profile of the rock-socketed pile was obtained by tracing the tested/failed piles after extracting them. The axial and lateral resistance of the rock-socketed piles are interpreted and discussed. It is observed that the rock-socketed piles behave in a distinctly different manner under combined loading compared with independent loading.","PeriodicalId":55099,"journal":{"name":"Geotechnical Testing Journal","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135010775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Black cotton soils are extremely problematic because they are susceptible to large volume changes with variation in moisture contents. These soils are conventionally stabilized with ordinary portland cement and lime, but the production/utilization of these traditional stabilizers is highly energy intensive, involves quarrying, and emits large quantities of carbon dioxide (CO2) into the atmosphere. Geopolymer is a promising alternative to these stabilizers because it provides high strength, consumes low energy, and emits low CO2 during synthesis and application. In this study, geopolymers synthesized from coal gangue (waste generated during coal mining) and ground granulated blast furnace slag (GGBS; by-product from the iron and steel industry) binders were evaluated for treating black cotton soil. A mixture of sodium silicate and sodium hydroxide is used as an alkaline activator solution for geopolymerization. An attempt is further made to identify the optimal dosages of geopolymer by evaluating the strength and durability characteristics of geopolymer-treated black cotton soil mixtures. X-ray diffraction and scanning electron microscopy were further conducted to distinguish the mineralogical and microstructural changes that occurred because of geopolymerization. From this study, it is found that using coal gangue alone as a precursor in geopolymer is good at improving the strength of black cotton soil but observed to be weak in durability. Hence, an attempt is further made to synthesize a better-performing geopolymer with a combination of GGBS and coal gangue, i.e., effective in both strength and durability aspects. Optimal geopolymer identified in this study can be a sustainable alternative to traditional stabilizers in improving black cotton soils for geotechnical subgrade applications.
{"title":"Performance Evaluation of Coal Gangue-GGBS–Based Geopolymer for Treating Black Cotton Soil","authors":"Aravind Gaddam, Sudheer Kumar Yamsani","doi":"10.1520/gtj20220251","DOIUrl":"https://doi.org/10.1520/gtj20220251","url":null,"abstract":"Black cotton soils are extremely problematic because they are susceptible to large volume changes with variation in moisture contents. These soils are conventionally stabilized with ordinary portland cement and lime, but the production/utilization of these traditional stabilizers is highly energy intensive, involves quarrying, and emits large quantities of carbon dioxide (CO2) into the atmosphere. Geopolymer is a promising alternative to these stabilizers because it provides high strength, consumes low energy, and emits low CO2 during synthesis and application. In this study, geopolymers synthesized from coal gangue (waste generated during coal mining) and ground granulated blast furnace slag (GGBS; by-product from the iron and steel industry) binders were evaluated for treating black cotton soil. A mixture of sodium silicate and sodium hydroxide is used as an alkaline activator solution for geopolymerization. An attempt is further made to identify the optimal dosages of geopolymer by evaluating the strength and durability characteristics of geopolymer-treated black cotton soil mixtures. X-ray diffraction and scanning electron microscopy were further conducted to distinguish the mineralogical and microstructural changes that occurred because of geopolymerization. From this study, it is found that using coal gangue alone as a precursor in geopolymer is good at improving the strength of black cotton soil but observed to be weak in durability. Hence, an attempt is further made to synthesize a better-performing geopolymer with a combination of GGBS and coal gangue, i.e., effective in both strength and durability aspects. Optimal geopolymer identified in this study can be a sustainable alternative to traditional stabilizers in improving black cotton soils for geotechnical subgrade applications.","PeriodicalId":55099,"journal":{"name":"Geotechnical Testing Journal","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135010777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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