Plasticity Based Liquefaction Criteria

Since their introduction into Chinese building codes in the 1970’s, plasticity-based liquefaction criteria have provided a means for evaluating the liquefaction susceptibility of sands with clayey fines. These criteria are used to separate soils that may be considered non-liquefiable from those susceptible to liquefaction. The majority of the proposed criteria contain some minimum requirement regarding clay content and soil plasticity. The results of a parametric study into the effects of plastic fines content and plasticity on the liquefaction susceptibility of sandy soils were used to evaluate the accuracy of several of the more commonly used plasticity-based liquefaction criteria. Most of the proposed criteria were found to have conservative requirements in terms of soil plasticity. Soils meeting the plasticity criteria were found to have very different deformation characteristics under cyclic loading than those soils not meeting the criteria. However, all the criteria reviewed were also found to include other requirements which were not accurate predictors of liquefaction susceptibility. In light of these findings, recommendations are provided for a simplified plasticity-based liquefaction criteria

Using Tactile Pressure Sensors to Measure Lateral Spreading Induced Earth Pressures Against a Large, Rigid Foundation

Two centrifuge tests were performed at the NEES facility at Rensselaer Polytechnic Institute (RPI) to observe lateral earth pressures mobilized against a rigid foundation element during liquefaction-induced lateral spreading, as part of a larger NEESR study aimed at developing novel approaches to mitigate the effects of seismically-induced ground failures on large, rigid foundation elements. Models were constructed in a laminar box to allow unimpeded downslope soil displacement, and the sand in the model was liquefied during the centrifuge test. Lateral pressures prior to, during, and after shaking and liquefaction were directly measured using a novel device: tactile pressure sensors. Prior to testing the production models, several 1g and centrifuge experiments were conducted to determine whether the tactile pressure sensors would accurately measure pressures. Using the tactile pressure sensor and configuration described in this paper, geostatic pressures measured prior to the shaking agreed well with the anticipated theoretical at-rest earth pressures. In this paper, we describe these initial tests, the challenges that were encountered, methods employed to overcome these challenges, and the production centrifuge tests

Importance of Echocardiography and Clinical "Red Flags" in Guiding Genetic Screening for Fabry Disease

Aim of this study was to evaluate, in a metropolitan area not already explored, the prevalence of Anderson-Fabry disease, by genetic screening, in patients with echocardiographic evidence of left ventricular hypertrophy (LVH) of unknown origin and "clinical red flags"

Epistasis between IL1A, IL1B, TNF, HTR2A, 5-HTTLPR and TPH2 Variations Does Not Impact Alcohol Dependence Disorder Features

We assessed a set of biological (HDL, LDL, SGOT, SGPT, GGT, HTc, Hb and T levels) and psychometric variables (investigated through HAM-D, HAM-A, GAS, Liebowitz Social Anxiety Scale, Mark & Mathews Scale, Leyton scale, and Pilowski scale) in a sample of 64 alcohol dependent patients, at baseline and after a detoxification treatment. Moreover, we recruited 47 non-consanguineous relatives who did not suffer alcohol related disorders and underwent the same tests. In both groups we genotyped 11 genetic variations (rs1800587; rs3087258; rs1799724; 5-HTTLPR; rs1386493; rs1386494; rs1487275; rs1843809; rs4570625; rs2129575; rs6313) located in genes whose impact on alcohol related behaviors and disorders has been hypothesized (IL1A, IL1B, TNF, 5-HTTLPR, TPH2 and HTR2A). We analyzed the epistasis of these genetic variations upon the biological and psychological dimensions in the cases and their relatives. Further on, we analyzed the effects of the combined genetic variations on the short – term detoxification treatment efficacy. Finally, being the only not yet investigated variation within this sample, we analyzed the impact of the rs6313 alone on baseline assessment and treatment efficacy. We detected the following results: the couple rs6313 + rs2129575 affected the Leyton -Trait at admission (p = 0.01) (obsessive-compulsive trait), whilst rs1800587 + 5-HTTLPR impacted the Pilowski test at admission (p = 0.01) (hypochondriac symptoms). These results did not survive Bonferroni correction (p ≤ 0.004). This lack of association may depend on the incomplete gene coverage or on the small sample size which limited the power of the study. On the other hand, it may reflect a substantial absence of relevance of the genotype variants toward the alcohol related investigated dimensions. Nonetheless, the marginal significance we detected could witness an informative correlation worth investigating in larger samples

Constant-Volume Cyclic Testing to Determine Input Parameters for the GMP Pore Pressure Generation Model

The GMP (Green, Mitchell and Polito) pore pressure generation model uses the energy dissipated in a soil during cyclic loading to predict the residual pore pressure rise in a saturated soil subjected to cyclic loading. In addition to the shear stresses and shear strains applied to the soil deposit being modeled, the GMP model requires a single calibration parameter referred to as the “pseudo energy capacity” or “PEC”. The study reported in this paper examined the validity of using constant-volume cyclic simple shear tests to develop values of the PEC for input into the GMP model. The study performed consisted of using the PEC developed from a series of constant-volume cyclic simple shear tests performed on a loose sand to predict the residual pore pressures generated during a series of stress- and strain-controlled cyclic triaxial tests performed on the same sand prepared to the same density. It was found that once the pseudoenergy capacities from the constant-volume cyclic simple shear tests were scaled to account for the effects of specimen size, they did an excellent job of predicting the pore pressure generation that occurred during the cyclic triaxial tests

On the Potential of Robust Satellite Techniques Approach for SPM Monitoring in Coastal Waters: Implementation and Application over the Basilicata Ionian Coastal Waters Using MODIS‐Aqua

Monitoring river plume dynamics and variations in complex coastal areas can provide useful information to prevent marine environmental damage. In this work, the Robust Satellite Techniques (RST) approach has been implemented and tested on historical series of Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) data to monitor, for the first time, Suspended Particulate Matter (SPM) anomalies associated to river plumes. To this aim, MODIS-Aqua Level 1A data were processed using an atmospheric correction adequate for coastal waters, and SPM daily maps were generated applying an algorithm adapted from literature. The RST approach was then applied to these maps to assess the anomalous presence of SPM. The study area involves the Basilicata region coastal waters (Ionian Sea, South of Italy). A long-time analysis (2003–2015) conducted for the month of December allows us to find that the maximum SPM concentration value was registered in December 2013, when an extreme hydrological event occurred. A short-time analysis was then carried out applying RST to monitor the dynamics of anomalous SPM concentrations. Finally, the most exposed areas, in terms of SPM concentration, were identified. The results obtained in this work showed the RST high potential when used in combination with standard SPM daily maps to better characterize and monitor coastal waters

IG II2 1237 and CID I 9: Sacrifices and Prebends in Athens and Delphi

This contribution consists of two parts: the first section is dedicated to Athens, the second one to Delphi. Through the examination of some short sections of two long epigraphic texts (the stele of the Demotionidai; the cippus of the Labyadai), very well known and discussed as significant for the structure of the community «minor units», but neglected by Moderns with regard to prebends and sacrifices and their relation to the polis, the contribution focuses on the sacrificial procedures and the prebends asso-ciated with them (IG II2 1237, col. I, ll. 4-8; CID I 9, face D, ll. 29-43) in order to highlight, in this way, the relationship between individual citizens and their minor units, the minor units and the polis, and, although exam-ining different sacrificial contexts, finds various points of contact between the mechanisms operating in the two poleis.Keywords: sacrifices, prebends

Threshold fines content and behavior of sands with nonplastic silts

The threshold fines content of a sand with nonplastic fines represents the silt content where the soil transitions from being a sand matrix, with silt particles entirely contained in the voids between the sands, to being a silt matrix that contains isolated sand grains. A laboratory testing program was performed on a series of mixtures of sand and silt, with silt contents ranging from 0% to 45%, to determine if the friction angle, cyclic resistance, and normalized dissipated energy per unit volume required to initiate liquefaction changed based upon the silt content of the soil relative to the threshold fines content. These data were evaluated with respect to whether the silt content of the specimens was below the lower-bound threshold fines content or above the upper-bound threshold fines content. It was determined that soils above the upper-bound threshold fines content had lower friction angles, lower cyclic resistances, and required less normalized dissipated energy per unit volume to initiate liquefaction than soils below the lower-bound threshold fines content. It was also shown that under the larger strains experienced during monotonic testing, the friction angle did not reach a constant value until it was well above the upper-bound limiting silt content.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

El Adelanto : Diario político de Salamanca: Año 48 Número 14688 - 1932 Marzo 12

The pore pressures generated in soils subjected to cyclic loadings have been shown to be proportional to the energy dissipated in the soil during that loading. Both stress-controlled and strain-controlled cyclic triaxial tests can be used to develop parameters for energy-based pore pressure models; however, the patterns of their energy dissipation into the soil are quite different. In this study, the two patterns of energy-dissipation associated with stress-controlled and strain-controlled cyclic triaxial tests were developed and then confirmed using sixteen stress-controlled and sixteen strain-controlled cyclic triaxial tests. Additionally, it was shown that the patterns of pore-pressure generation for the two tests, which differ greatly when evaluated relative to the cycles of loading, were very similar when evaluated in terms of their energy dissipation

Reply to the discussion by Dallo on “Threshold fines content and behavior of sands with nonplastic silts”

A reply to the discussion submitted by Yosif Dallo of the authors' paper entitled, “Threshold Fines Content and the Behavior of Sands with Non-Plastic Silts” is provided. The reply clarifies and expands upon several points raised by Dr. Dallo.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author