Documents disponibles écrits par cet auteur

Aging of crushed glass-dredged material blend embankments / Dennis G. Grubb in Journal of geotechnical and geoenvironmental engineering, Vol. 134 n°11 (Novembre 2008) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 134 n°11 (Novembre 2008) . - pp. 1676–1684 Titre : Aging of crushed glass-dredged material blend embankments Type de document : texte imprimé Auteurs : Dennis G. Grubb, Auteur ; Joseph Wartman, Auteur ; Nicholas E. Malasavage, Auteur Année de publication : 2009 Article en page(s) : pp. 1676–1684 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Laboratory  tests  Recycling  Glass  Dredge  spoil  Physical  properties  Aging  Penetrometers  Embankments Résumé : Four crushed glass (CG) and dredged material (DM) [(CG-DM)] blend embankments constructed (2004) and reconstructed (2005) to local DOT specifications were subjected to cone penetrometer tests (CPT). The CPT resistance of the original set of embankments was evaluated shortly after construction and approximately 360days later, immediately prior to being demolished for purposes of a second study. Cone tip resistances were observed to double to triple with aging. For the 80∕20 CG-DM blend, a 4MPa [40 tons per square foot (tsf)] or threefold increase in CPT tip resistance was measured. Likewise, isotropically consolidated, undrained triaxial shear tests were performed on relatively undisturbed thin-walled tube specimens of the 360-day aged CG-DM blend materials. The triaxial tests revealed that the effective friction angles of the aged materials increased by up to 8° over freshly prepared laboratory CG-DM blend specimens. The strength gains appeared to be more strongly linked to (amorphous) silica cementation rather than the formation of carbonates. Disturbance (demolition and reconstruction) generally reduced the in situ CPT behavior to that of the originally constructed embankments. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A11%281 [...] [article] Aging of crushed glass-dredged material blend embankments [texte imprimé] / Dennis G. Grubb, Auteur ; Joseph Wartman, Auteur ; Nicholas E. Malasavage, Auteur . - 2009 . - pp. 1676–1684. Geotechnical and geoenvironmental engineering Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 134 n°11 (Novembre 2008) . - pp. 1676–1684 Mots-clés : Laboratory  tests  Recycling  Glass  Dredge  spoil  Physical  properties  Aging  Penetrometers  Embankments Résumé : Four crushed glass (CG) and dredged material (DM) [(CG-DM)] blend embankments constructed (2004) and reconstructed (2005) to local DOT specifications were subjected to cone penetrometer tests (CPT). The CPT resistance of the original set of embankments was evaluated shortly after construction and approximately 360days later, immediately prior to being demolished for purposes of a second study. Cone tip resistances were observed to double to triple with aging. For the 80∕20 CG-DM blend, a 4MPa [40 tons per square foot (tsf)] or threefold increase in CPT tip resistance was measured. Likewise, isotropically consolidated, undrained triaxial shear tests were performed on relatively undisturbed thin-walled tube specimens of the 360-day aged CG-DM blend materials. The triaxial tests revealed that the effective friction angles of the aged materials increased by up to 8° over freshly prepared laboratory CG-DM blend specimens. The strength gains appeared to be more strongly linked to (amorphous) silica cementation rather than the formation of carbonates. Disturbance (demolition and reconstruction) generally reduced the in situ CPT behavior to that of the originally constructed embankments. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A11%281 [...]

Assessment of sulfate-induced swell in stabilized dredged material / Maria Chrysochoou in Journal of geotechnical and geoenvironmental engineering, Vol. 138 N° 3 (Mars 2012) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 3 (Mars 2012) . - pp. 407-414 Titre : Assessment of sulfate-induced swell in stabilized dredged material : Is ettringite always a problem? Type de document : texte imprimé Auteurs : Maria Chrysochoou, Auteur ; Dennis G. Grubb, Auteur ; Nicholas E. Malasavage, Auteur Année de publication : 2012 Article en page(s) : pp. 407-414 Note générale : Géotechnique Langues : Anglais (eng) Mots-clés : Swelling  Sulfate  Dredge  spoil  Cement  Lime  Cement  kiln  dust  Soil  mixing Résumé : This paper is the last in a series related to pozzolanically stabilizing dredged material (DM) using up to 20 different combinations of lime, cement kiln dust (CKD), fly ash (FA), Portland cement (PC), and slag cement. The fine-grained nature of the DM and the presence of high sulfate concentrations (0.6–3.25% by weight) in the stabilized dredged material (SDM) blends derived from the raw materials themselves posed concern for potential ettringite formation and swell. The sulfate contents of the SDM blends were well in excess of the National Lime Association’s thresholds for mitigating against swell (<0.8% by weight SO4). The quantitative mineralogical results showed that the lime and lime/FA SDM blends showed moderate to high ettringite formation (1.6–4.6% by weight) up to 6 months of curing, with all available sulfate bound to ettringite. The lime and lime/FA SDM blends consistently maintained the highest pHs through 6 months, which caused continued release of alumina and increases in strength. The CKD and CKD/FA SDM blends showed the highest ettringite contents through 28 days of curing (up to 5%), but with little additional formation of ettringite through 6 months of curing. The total sulfate content of the SDM blends was not a good predictor of ettringite formation potential, because of decreases in pH below the ettringite stability threshold and, even more importantly, the apparent limited availability of soluble alumina in the SDM blends. Swell tests performed on six SDM blends showed slight consolidation, and no ettringite was detected in the two specimens that swelled. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v138/i3/p407_s1?isAuthorized=no [article] Assessment of sulfate-induced swell in stabilized dredged material : Is ettringite always a problem? [texte imprimé] / Maria Chrysochoou, Auteur ; Dennis G. Grubb, Auteur ; Nicholas E. Malasavage, Auteur . - 2012 . - pp. 407-414. Géotechnique Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 3 (Mars 2012) . - pp. 407-414 Mots-clés : Swelling  Sulfate  Dredge  spoil  Cement  Lime  Cement  kiln  dust  Soil  mixing Résumé : This paper is the last in a series related to pozzolanically stabilizing dredged material (DM) using up to 20 different combinations of lime, cement kiln dust (CKD), fly ash (FA), Portland cement (PC), and slag cement. The fine-grained nature of the DM and the presence of high sulfate concentrations (0.6–3.25% by weight) in the stabilized dredged material (SDM) blends derived from the raw materials themselves posed concern for potential ettringite formation and swell. The sulfate contents of the SDM blends were well in excess of the National Lime Association’s thresholds for mitigating against swell (<0.8% by weight SO4). The quantitative mineralogical results showed that the lime and lime/FA SDM blends showed moderate to high ettringite formation (1.6–4.6% by weight) up to 6 months of curing, with all available sulfate bound to ettringite. The lime and lime/FA SDM blends consistently maintained the highest pHs through 6 months, which caused continued release of alumina and increases in strength. The CKD and CKD/FA SDM blends showed the highest ettringite contents through 28 days of curing (up to 5%), but with little additional formation of ettringite through 6 months of curing. The total sulfate content of the SDM blends was not a good predictor of ettringite formation potential, because of decreases in pH below the ettringite stability threshold and, even more importantly, the apparent limited availability of soluble alumina in the SDM blends. Swell tests performed on six SDM blends showed slight consolidation, and no ettringite was detected in the two specimens that swelled. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v138/i3/p407_s1?isAuthorized=no

Geotechnical performance of dredged material—steel slag fines blends / Nicholas E. Malasavage in Journal of geotechnical and geoenvironmental engineering, Vol. 138 N° 8 (Août 2012) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 8 (Août 2012) . - pp. 981–991 Titre : Geotechnical performance of dredged material—steel slag fines blends : Laboratory and field evaluation Type de document : texte imprimé Auteurs : Nicholas E. Malasavage, Auteur ; Santhi Jagupilla, Auteur ; Dennis G. Grubb, Auteur Année de publication : 2012 Article en page(s) : pp. 981–991 Note générale : Géotechnique Langues : Anglais (eng) Mots-clés : Field  tests  Recycling  Slag  Dredge  spoils  Physical  properties  Soil  mixing  Embankment  Cone  penetration  tests Résumé : This paper contains the results of a combined laboratory and field demonstration project exploring the use of dredged material (DM) blended with steel slag fines [SSF; 9.5 mm (3/8  in.) minus] as synthetic fill materials. The granular nature [a well graded sand (SW) soil], mineralogy, reactivity, and residual lime content of the SSF media make it well suited for blending with DM high-plasticity organic (OH) soil, so that geotechnical and environmental soil improvement occur simultaneously with one amendment. The source materials (100% DM, 100% SSF) were evaluated along with 80/20, 60/40, 50/50, 40/60, and 20/80 DM-SSF blends (dry weight basis), where the DM content is reported first. Key findings include that the 100% DM had a ϕ′CIU¯¯¯ of 27.3°, which increased to a peak ϕ′CIU¯¯¯ value of 45° for the 50/50 DM-SSF blend. The hydraulic conductivity (k) of the 100% DM (10−8  cm/s) remained relatively constant until SSF content reached 80%, where an abrupt increase to 10−5  cm/s was observed. The field demonstration project confirmed that the DM-SSF blends could be easily blended to within ±5% of their target DM content. Trial highway embankments were constructed with 100% DM, 100% SSF, and the 80/20, 50/50, and 20/80 DM-SSF blends to modified Proctor compaction goals ranging from 85 to 95% relative compaction on the maximum dry unit weight, depending on the blend. The average cone penetration test (CPT) tip resistance for 100% DM and 100% SSF media were approximately 1.3 and 57.3 MPa, respectively. The compacted 80/20, 50/50, and 20/80 DM-SSF blend embankments were generally characterized by average CPT tip resistances on the order of 2.9, 6.2, and 11.6 MPa, respectively. ISSN : 1090-0241 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000658 [article] Geotechnical performance of dredged material—steel slag fines blends : Laboratory and field evaluation [texte imprimé] / Nicholas E. Malasavage, Auteur ; Santhi Jagupilla, Auteur ; Dennis G. Grubb, Auteur . - 2012 . - pp. 981–991. Géotechnique Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 8 (Août 2012) . - pp. 981–991 Mots-clés : Field  tests  Recycling  Slag  Dredge  spoils  Physical  properties  Soil  mixing  Embankment  Cone  penetration  tests Résumé : This paper contains the results of a combined laboratory and field demonstration project exploring the use of dredged material (DM) blended with steel slag fines [SSF; 9.5 mm (3/8  in.) minus] as synthetic fill materials. The granular nature [a well graded sand (SW) soil], mineralogy, reactivity, and residual lime content of the SSF media make it well suited for blending with DM high-plasticity organic (OH) soil, so that geotechnical and environmental soil improvement occur simultaneously with one amendment. The source materials (100% DM, 100% SSF) were evaluated along with 80/20, 60/40, 50/50, 40/60, and 20/80 DM-SSF blends (dry weight basis), where the DM content is reported first. Key findings include that the 100% DM had a ϕ′CIU¯¯¯ of 27.3°, which increased to a peak ϕ′CIU¯¯¯ value of 45° for the 50/50 DM-SSF blend. The hydraulic conductivity (k) of the 100% DM (10−8  cm/s) remained relatively constant until SSF content reached 80%, where an abrupt increase to 10−5  cm/s was observed. The field demonstration project confirmed that the DM-SSF blends could be easily blended to within ±5% of their target DM content. Trial highway embankments were constructed with 100% DM, 100% SSF, and the 80/20, 50/50, and 20/80 DM-SSF blends to modified Proctor compaction goals ranging from 85 to 95% relative compaction on the maximum dry unit weight, depending on the blend. The average cone penetration test (CPT) tip resistance for 100% DM and 100% SSF media were approximately 1.3 and 57.3 MPa, respectively. The compacted 80/20, 50/50, and 20/80 DM-SSF blend embankments were generally characterized by average CPT tip resistances on the order of 2.9, 6.2, and 11.6 MPa, respectively. ISSN : 1090-0241 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000658

Stabilized dredged material. II, Geomechanical behavior / Dennis G. Grubb in Journal of geotechnical and geoenvironmental engineering, Vol. 136 N° 8 (Août 2010) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 136 N° 8 (Août 2010) . - pp. 1025-1036 Titre : Stabilized dredged material. II, Geomechanical behavior Type de document : texte imprimé Auteurs : Dennis G. Grubb, Auteur ; Nicholas E. Malasavage, Auteur ; Charles J. Smith, Auteur Année de publication : 2010 Article en page(s) : pp. 1025-1036 Note générale : Géotechnique Langues : Anglais (eng) Mots-clés : Soil  stabilization  Soil  cement  Dredge  spoil  Byproduct  utilization  Laboratory  tests  Physical  properties Index. décimale : 624.1 Infrastructures.Ouvrages en terre. Fondations. Tunnels Résumé : This study presents the results of a detailed geotechnical evaluation of six stabilized dredged material (SDM) blends incorporating various combinations of lime, cement kiln dust, high alkali and slag cements, and Class F fly ash. The dredged material classified as CH/OH soil with an in situ moisture content (MC) of approximately 130% and void ratio of 3.35. Mix designs and unconfined compression strength tests were completed for each SDM blend based on 3-day mellowing characteristics. Compacted dry densities were on the order of 7.8–11.2 kN/m3 (49–71 lb/ft3), with MCs on the order of 34–73%. Peak effective friction angles ranged from 20–50° with cohesion intercepts on the order of 30–235 kPa (4–34 lb/in.2) using a maximum stress obiliquity criterion. Postpeak effective friction angles (15% axial strain) were routinely in excess of 40° with low cohesion (<40 kPa; 6 lb/in.2). One sample exhibited very strong soil-fabric effects (cohesion) having an effective friction angle of only approximately 9°, but cohesion on the order of 450 kPa (65 lb/in.2). Negligible consolidation of a 28-day cured sample was measured. Also, contrary to expectations based on the high sulfate contents (10,000–30,000 mg/kg) of the SDM blends, negligible swell (<1%) was measured in five of six SDM blends. The main finding of this research is the SDM blends exhibit the strength, compressibility, and bulking characteristics that make them favorable for large fill applications and subgrade improvement applications at costs equivalent to or less than conventional construction materials. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v136/i8/p1025_s1?isAuthorized=no [article] Stabilized dredged material. II, Geomechanical behavior [texte imprimé] / Dennis G. Grubb, Auteur ; Nicholas E. Malasavage, Auteur ; Charles J. Smith, Auteur . - 2010 . - pp. 1025-1036. Géotechnique Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 136 N° 8 (Août 2010) . - pp. 1025-1036 Mots-clés : Soil  stabilization  Soil  cement  Dredge  spoil  Byproduct  utilization  Laboratory  tests  Physical  properties Index. décimale : 624.1 Infrastructures.Ouvrages en terre. Fondations. Tunnels Résumé : This study presents the results of a detailed geotechnical evaluation of six stabilized dredged material (SDM) blends incorporating various combinations of lime, cement kiln dust, high alkali and slag cements, and Class F fly ash. The dredged material classified as CH/OH soil with an in situ moisture content (MC) of approximately 130% and void ratio of 3.35. Mix designs and unconfined compression strength tests were completed for each SDM blend based on 3-day mellowing characteristics. Compacted dry densities were on the order of 7.8–11.2 kN/m3 (49–71 lb/ft3), with MCs on the order of 34–73%. Peak effective friction angles ranged from 20–50° with cohesion intercepts on the order of 30–235 kPa (4–34 lb/in.2) using a maximum stress obiliquity criterion. Postpeak effective friction angles (15% axial strain) were routinely in excess of 40° with low cohesion (<40 kPa; 6 lb/in.2). One sample exhibited very strong soil-fabric effects (cohesion) having an effective friction angle of only approximately 9°, but cohesion on the order of 450 kPa (65 lb/in.2). Negligible consolidation of a 28-day cured sample was measured. Also, contrary to expectations based on the high sulfate contents (10,000–30,000 mg/kg) of the SDM blends, negligible swell (<1%) was measured in five of six SDM blends. The main finding of this research is the SDM blends exhibit the strength, compressibility, and bulking characteristics that make them favorable for large fill applications and subgrade improvement applications at costs equivalent to or less than conventional construction materials. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v136/i8/p1025_s1?isAuthorized=no