- Email: [email protected]
Collapse of large tanks due to excessive settlement differences
187A 933372
Colialme of large tanks due to exce~ve settlement dfmereuees Farkas, J; Kovacs, M Proc lOth Fawopean Conference om Soil Meclmnics and Fmmdation ~ e r i q , Florence, 26-30 May 1991 V1, P393395. Publ Rotterdam: A A Balkema, 1991 An array of fermentation tanks for a brewery was constructed with each supported by 4 pillars of a raster, with block foundations for the pillars on 5-7m of loess. Internal columns settied 200-300ram on first loading, external pillars only 2070ram, and collapse of the tanks resulted. On economic grounds it was necessary to reuse the block foundations. Strengthening by surrounding them with 9m deep trench pillars was selected ahead of piling or construction of a continuous concrete slab. Maximum settlement after treatment was 8mm. 933373 Large di~qplaeements of a bridge foundation on a slope - its stabilization by a pore pressure relief screen Fnchsberger, M Prnc lOth European Conference on Soil Mechanics and Foundation Engineering, Florence, 26-30 May 1991 I/1, P397401. Publ Rotterdam: A A Balkema, 1991 The Vieuna-Graz motorway crosses in parts unstable slopes with a multilayered red soil of periglacial origin. Such soil is prone to creep, especially if disturbed by construction activity. Structural damage became evident at one bridge and subsequent investigations showed a slip surface had developed below the base of one pier and the slope and the pier were creeping downslope. Pore pressure buildup in a sandy seam was considered to be responsible for the development of creep. Remedial measures of a pore pressure relief screen (vertical drainage piles) and underpinning have stabilised the pier. 933374 Characterization of soft properties from large scale load tests Gatti, G; Cividini, A; Galloni, G Proc lOth European Conference on Soil Meclumics and Fomulation En "gmeering,Florence, 26-30 May 1991 I/1, 1'407412. Publ Rotterdam: A A Balkema, 1991 Results of load tests on two large tanks founded on layered alluvium (mainly sand and gravel) are presented and compared to settlements predicted by finite element analysis at the design stage and from a simplified analysis assuming uniform soil. The characteristics of the analysis method appear to have little effect on the accuracy of the results, provided variation of elastic properties with depth is described in adequate detail. Penetrometer tests are suggested for derivation of these elastic properties. 933375
Settlements of large shallow foundations on a partially cemented gravelly sand deposit using PLT data Ghionna, V N; Manassero, M; Peisino, V Proc lOth European Conference on Soil Mechanics and Foandation Engineering, Florence, 26-30 May 1991 V1, P417422. Publ Rotterdam: A A Balkema, 1991 When designing shallow foundations on gravelly soils, settlement prediction is made difficult by the inability to recover undisturbed samples and the doubtful reliability of SPT and CPT tests. If the deposits are uniform, settlement may be predicted on the basis of linear elastic theory with the appropriate deformation parameters. A procedure based on plate loading tests and a hyperbolic soil model is presented for determination of these parameters. An expression to evaluate settlement
using these parameters is given. It is verified using data from large foundation structures and the results compared to those based on SPT and CPT data.
933376
Analysis of frames on elastic soils or normally consolidated days Aytekin, M Proc 28th Symposhun on E~,ineering Geology and Geotecimieal E ~ e r i n g , Boise, 1-3 April 1992 P180-192. Publ Pocatello: Idaho State University, 1992 The assumption of fixed support in plane frame analysis is not generally valid as soil or even rock media may show considerable elastic settlement once a load is applied. A model which considers deflection of supports due to elastic or consolidation settlements should be applied. Such a model is presented for elastic soils or normally consolidated clays. The soil medium is represented by an infinite number of springs which have three components: vertical settlement, horizontal movement, and rotation of the footing of the frame. Spring coefficients are estimated as functions of soil elastic properties and size, shape, and loading of the footings. Examples are presented which show the difference in internal load distributions between fixed and spring-supported frames.
933377 Development of economical solutions to mitigate geoteclmical risks: Walpnoa Water Treatment Augmentation Plant Brabhaharan, P; Vessey, J V Proc 6th Am~ralia-New Zealmul Conference on Geomeckanics, Christchurch, 3-7 February 1992 P489-494. Publ New Zealand: New Zealand Geomechanics Society, 1992 The Waipaoa site on the North Island of New Zealand has a profile of predominantly soft clayey and sandy silts to a depth about 12m, then silty clay and clayey silt. Initial assessment indicated a high risk of damage to the main plant due to settlement and a moderate risk due to liquefaction-induced damage during large earthquake events. Economic assessment balanced costs of damage against costs of mitigation measures over the design life of the project. Site improvement by preloading, dynamic compaction, or both these measures was considered. The solution adopted was to use preloading, minimising risk of settlement but accepting risk of liquefaction.
933378 Appficntion of zero extension line in bearing capacity Behpoor, L; Ghahramani, A Proc Ninth Asian Regional Conference on Soil Mechanics and Foandmian Engineering, Bangkok, 9-13 December 1991 VI, P19-22. Publ Thailand." Southeast Asian Geotechnical Society, 1991 The zero extension line concept, first proposed by Roscoe in 1970 for the interpretation of the strain field in granular media, has been applied to evaluate the bearing capacity of shallow, smooth strip foundations on sandy soil. Predictions agree well with other values cited in the literature. The settlement of the footing produces a constant shear strain in soil elements in the Goursat and Rankine zones, the magnitude of which is twice the relative settlement of the foundation (settlement/width of the footing). Shear test results relating friction angle to shear strain can be used to predict bearing pressure at a given settlement and vice versa.
© 1993 Pergamon Press Ltd. Reproduction not permitted
Colialme of large tanks due to exce~ve settlement dfmereuees Farkas, J; Kovacs, M Proc lOth Fawopean Conference om Soil Meclmnics and Fmmdation ~ e r i q , Florence, 26-30 May 1991 V1, P393395. Publ Rotterdam: A A Balkema, 1991 An array of fermentation tanks for a brewery was constructed with each supported by 4 pillars of a raster, with block foundations for the pillars on 5-7m of loess. Internal columns settied 200-300ram on first loading, external pillars only 2070ram, and collapse of the tanks resulted. On economic grounds it was necessary to reuse the block foundations. Strengthening by surrounding them with 9m deep trench pillars was selected ahead of piling or construction of a continuous concrete slab. Maximum settlement after treatment was 8mm. 933373 Large di~qplaeements of a bridge foundation on a slope - its stabilization by a pore pressure relief screen Fnchsberger, M Prnc lOth European Conference on Soil Mechanics and Foundation Engineering, Florence, 26-30 May 1991 I/1, P397401. Publ Rotterdam: A A Balkema, 1991 The Vieuna-Graz motorway crosses in parts unstable slopes with a multilayered red soil of periglacial origin. Such soil is prone to creep, especially if disturbed by construction activity. Structural damage became evident at one bridge and subsequent investigations showed a slip surface had developed below the base of one pier and the slope and the pier were creeping downslope. Pore pressure buildup in a sandy seam was considered to be responsible for the development of creep. Remedial measures of a pore pressure relief screen (vertical drainage piles) and underpinning have stabilised the pier. 933374 Characterization of soft properties from large scale load tests Gatti, G; Cividini, A; Galloni, G Proc lOth European Conference on Soil Meclumics and Fomulation En "gmeering,Florence, 26-30 May 1991 I/1, 1'407412. Publ Rotterdam: A A Balkema, 1991 Results of load tests on two large tanks founded on layered alluvium (mainly sand and gravel) are presented and compared to settlements predicted by finite element analysis at the design stage and from a simplified analysis assuming uniform soil. The characteristics of the analysis method appear to have little effect on the accuracy of the results, provided variation of elastic properties with depth is described in adequate detail. Penetrometer tests are suggested for derivation of these elastic properties. 933375
Settlements of large shallow foundations on a partially cemented gravelly sand deposit using PLT data Ghionna, V N; Manassero, M; Peisino, V Proc lOth European Conference on Soil Mechanics and Foandation Engineering, Florence, 26-30 May 1991 V1, P417422. Publ Rotterdam: A A Balkema, 1991 When designing shallow foundations on gravelly soils, settlement prediction is made difficult by the inability to recover undisturbed samples and the doubtful reliability of SPT and CPT tests. If the deposits are uniform, settlement may be predicted on the basis of linear elastic theory with the appropriate deformation parameters. A procedure based on plate loading tests and a hyperbolic soil model is presented for determination of these parameters. An expression to evaluate settlement
using these parameters is given. It is verified using data from large foundation structures and the results compared to those based on SPT and CPT data.
933376
Analysis of frames on elastic soils or normally consolidated days Aytekin, M Proc 28th Symposhun on E~,ineering Geology and Geotecimieal E ~ e r i n g , Boise, 1-3 April 1992 P180-192. Publ Pocatello: Idaho State University, 1992 The assumption of fixed support in plane frame analysis is not generally valid as soil or even rock media may show considerable elastic settlement once a load is applied. A model which considers deflection of supports due to elastic or consolidation settlements should be applied. Such a model is presented for elastic soils or normally consolidated clays. The soil medium is represented by an infinite number of springs which have three components: vertical settlement, horizontal movement, and rotation of the footing of the frame. Spring coefficients are estimated as functions of soil elastic properties and size, shape, and loading of the footings. Examples are presented which show the difference in internal load distributions between fixed and spring-supported frames.
933377 Development of economical solutions to mitigate geoteclmical risks: Walpnoa Water Treatment Augmentation Plant Brabhaharan, P; Vessey, J V Proc 6th Am~ralia-New Zealmul Conference on Geomeckanics, Christchurch, 3-7 February 1992 P489-494. Publ New Zealand: New Zealand Geomechanics Society, 1992 The Waipaoa site on the North Island of New Zealand has a profile of predominantly soft clayey and sandy silts to a depth about 12m, then silty clay and clayey silt. Initial assessment indicated a high risk of damage to the main plant due to settlement and a moderate risk due to liquefaction-induced damage during large earthquake events. Economic assessment balanced costs of damage against costs of mitigation measures over the design life of the project. Site improvement by preloading, dynamic compaction, or both these measures was considered. The solution adopted was to use preloading, minimising risk of settlement but accepting risk of liquefaction.
933378 Appficntion of zero extension line in bearing capacity Behpoor, L; Ghahramani, A Proc Ninth Asian Regional Conference on Soil Mechanics and Foandmian Engineering, Bangkok, 9-13 December 1991 VI, P19-22. Publ Thailand." Southeast Asian Geotechnical Society, 1991 The zero extension line concept, first proposed by Roscoe in 1970 for the interpretation of the strain field in granular media, has been applied to evaluate the bearing capacity of shallow, smooth strip foundations on sandy soil. Predictions agree well with other values cited in the literature. The settlement of the footing produces a constant shear strain in soil elements in the Goursat and Rankine zones, the magnitude of which is twice the relative settlement of the foundation (settlement/width of the footing). Shear test results relating friction angle to shear strain can be used to predict bearing pressure at a given settlement and vice versa.
© 1993 Pergamon Press Ltd. Reproduction not permitted