8,478 research outputs found
Hydro‐mechanically Coupled Interface Finite Element for the Modeling of Soil–Structure Interactions: Application to Offshore Constructions
No full textpeer reviewe
Implicit implementation of the Prevost model: 25th ALERT Workshop
No full textThe Prevost model for cohesionless soils (Prevost 1985) is currently used for the modelling of their cyclic behaviour, especially in earthquake engineering (Zerfa and Loret 2003) and (Yang and Elgamal 2008). It’s made of conical yield surfaces that allow for plastic deformations in both loading and unloading. Its non-associated volumetric flow rule can roughly take into account pore pressure build-up and cyclic mobility. The method of implementation of a constitutive law is a crucial issue (Montáns and Caminero 2007) and (Mira et al. 2009). On one hand the accuracy of the solution must be ensured, especially when a large number of cycles are considered. But on the other hand, the cost of the computation must be minimized which implies step size as large as possible. In this paper, an implicit implementation of the Prevost model is proposed. The plastic flow rule is computed through a trapezoidal rule, at the time step n + 1/2, in order to increase the accuracy.An iterative process has to be solved, due to the implicit formulation.The Jacobian matrix of the internal Newton-Raphson process is computed analytically to enhance efficiency. The algorithm is implemented in the finite element code LAGAMINE that carries out fully-coupled analysis. Simulations of triaxial tests are compared with “exact” solution
J.C. Painter letter to Benjamin Lundy
No full textLetter from J.E. Painter to (presumably) Benjamin Lundy, answering a request for information about the history and operations of the Underground Railroad. Letter includes details of a story of an ex-slave transported on the Underground Railroad through Ohio and stories of the plight of other fugitive slaves crossing the Ohio River.
Benjamin Lundy (1789-1839) was a prominent Quaker abolitionist best known for his development of abolitionist periodicals. His "Genius of Universal Emancipation" was first published in 1821 from his home in Mt. Pleasant, Ohio, and enjoyed a wide circulation across the antebellum United States. In the 1820s, the young William Lloyd Garrison came to work for The Genius. Benjamin Lundy traveled widely seeking subscriptions to The Genius, giving talks about the anti-slavery movement, and observing and documenting the conditions of enslaved people across the Americas. He was also involved in the establishment of freed slave colonies in Mexico
Mexican land grant contract to Benjamin Lundy, March 10, 1835 (English)
No full textLegal document from an unsigned officer to Benjamin Lundy, authorizing him rights as empresario to a tract of land in then-Mexico. The document extends a previous treaty made to Lundy by the government of Mexico from November 17, 1823 -- presumably, this land is to be the site of Lundy's freed slave colony. Original Spanish-language document is also a part of this collection. Benjamin Lundy (1789-1839) was a prominent Quaker abolitionist best known for his development of abolitionist periodicals. His Genius of Universal Emancipation was first published in 1821 from his home in Mt. Pleasant, Ohio, and enjoyed a wide circulation across the antebellum United States. In the 1820s, the young William Lloyd Garrison came to work for The Genius. Benjamin Lundy traveled widely seeking subscriptions to The Genius, giving talks about the anti-slavery movement, and observing and documenting the conditions of enslaved people across the Americas. He was also involved in the establishment of freed slave colonies in Mexico
Eli Nichols letter to Benjamin Lundy, March 17th, 1839
No full textFriendly note from Eli Nichols to Benjamin Lundy covering topics in contemporary abolition, ranging from the social status of abolitionists to the oppression of the poor. Much of the letter concerns a review of contemporary social movements in equality-based education, including Shaker and Quaker communities. The letter concludes in discussion of Nichols' and Lundy's interest in forming a freed slave colony or community in then-Mexico, and describes the climate and culture of those regions in detail. Benjamin Lundy (1789-1839) was a prominent Quaker abolitionist best known for his development of abolitionist periodicals. His Genius of Universal Emancipation was first published in 1821 from his home in Mt. Pleasant, Ohio, and enjoyed a wide circulation across the antebellum United States. In the 1820s, the young William Lloyd Garrison came to work for The Genius. Benjamin Lundy traveled widely seeking subscriptions to The Genius, giving talks about the anti-slavery movement, and observing and documenting the conditions of enslaved people across the Americas. He was also involved in the establishment of freed slave colonies in Mexico
Mexican land grant contract to Benjamin Lundy, March 10, 1835 (Spanish)
No full textLegal document in Spanish from the government of Tamaulipas, Mexico, to Benjamin Lundy, which appears to grant Lundy the rights of empresario for his proposed colony for freed slaves in Tamaulipas. This document appears to be truncated; it ends abruptly after 2 pages. Collection also includes a period translation of this contract with Lundy in English, which appears to contain the full text of the agreement. Benjamin Lundy (1789-1839) was a prominent Quaker abolitionist best known for his development of abolitionist periodicals. His Genius of Universal Emancipation was first published in 1821 from his home in Mt. Pleasant, Ohio, and enjoyed a wide circulation across the antebellum United States. In the 1820s, the young William Lloyd Garrison came to work for The Genius. Benjamin Lundy traveled widely seeking subscriptions to The Genius, giving talks about the anti-slavery movement, and observing and documenting the conditions of enslaved people across the Americas. He was also involved in the establishment of freed slave colonies in Mexico
General Benjamin Butler Letter Regarding the naming of Newport News, Virginia
No full textDigital images of an original letter written by Former Union Major-General Benjamin Butler in reply to a query by author, Edwin Everett Hale on how Newport News, Virginia had received it's name. both sides of the original letter are included along with a typed transcription of the letter
Numerical modelling of transient cyclic vertical loading of suction caissons in sand
No full textpeer reviewedThis paper presents numerical investigations of the monotonic and cyclic behaviours of suction caissons upon vertical transient loading. Both drained and partially drained conditions are investigated. Monotonic compression and traction simulations are carried out to qualitatively compare results with the literature and validate the model. They highlight the different modes of reaction of the caisson to both compression and traction loading. A sensitivity analysis points out the strong influence of some parameters on the resistance of the caisson but also on the failure mechanism. The transient behaviour of the caisson upon different kinds of cyclic load signals is analysed. Results reproduce the settlement and pore water pressure accumulations observed during experiments. The influence of the key design parameters on the settlement accumulation is also assessed. Finally a cyclic diagram is proposed to describe the evolution of the final settlement upon different magnitudes of loading
Cinq années de voyage en Orient 1846-1851 par Israel-Joseph Benjamin II, voyageur et auteur, demeurant à Faltischan (Moldavie). Paris en vente chez Michel Levy Frères, rue Vivienne, 2 bis 1856 L' auteur se réserve le droit de traduction et de reproduction
No full textPreface: by Benjamin, J.Dedication: by the author to M.J. Altaras aîné de Marseille et M. Albert Cohn.Content description: Detailed contentsPagination: PP28+240PVolumes: 1Text Genre:Pros
Validation of a new elastoplastic constitutive model dedicated to the cyclic behaviour of brittle rock materials
No full textpeer reviewedOld mines or caverns may be used as reservoirs for fuel/gas storage or in the context of large-scale energy storage. In the first case, oil or gas is stored on annual basis. In the second case pressure due to water or compressed air varies on a daily basis or even faster. In both cases a cyclic loading on the cavern’s/mine’s walls must be considered for the design. The complexity of rockwork geometries or coupling with water flow requires finite element modelling and then a suitable constitutive law for the rock behaviour modelling. This paper presents and validates the formulation of a new constitutive law able to represent the inherently cyclic behaviour of rocks at low confinement. The main features of the behaviour evidenced by experiments in the literature depict a progressive degradation and strain of the material with the number of cycles. A constitutive law based on a boundary surface concept is developed. It represents the brittle failure of the material as well as its progressive degradation. Kinematic hardening of the yield
surface allows the modelling of cycles. Isotropic softening on the cohesion variable leads to the progressive degradation of the rock strength. A limit surface is introduced and has a lower opening than the bounding surface. This surface describes the peak strength of the material andallows the modelling of a brittle behaviour. In addition a fatigue limit is introduced such that no cohesion degradation occurs if the stress state lies inside this surface. The model is validated against three different rock materials and types of experiments. Parameters of the constitutive
laws are calibrated against uniaxial tests on Lorano marble, triaxial test on a sandstone and damage-controlled test on Lac du Bonnet granite. The model is shown to reproduce correctly experimental results, especially the evolution of strain with number of cycles.SMARTWATE
- …
