scholarly journals The importance of designer-contractor communication in geotechnical design as exemplified by a cut slope failure

2020 ◽  
Vol 800 (1) ◽  
pp. 012004
Author(s):  
D Anafarta ◽  
E Turk ◽  
S O Akbas

Abstract A shallow slope failure has occurred on the cut slopes of the Bigadic-Simav-Abide highway at the section located between Km:125+530-125+870, during construction. A detailed investigation of the landslide mechanism, which includes site specific surveys, laboratory studies, and stability analyses indicates that the main reason of the failure lies within the construction procedure details. This study focuses on the forensic geotechnical engineering procedures applied for determining the cause of the slope failure. An emphasis was placed on the importance of strictly following the construction sequence as illustrated in the design documents in detail, as well as on the indispensable role of continuous communication between the designer and the contractor for successful performance of geotechnical works.

2021 ◽  
Author(s):  
Mincheol Park ◽  
Heuisoo Han ◽  
Yoonhwa Jin

In the process of constructing roads for the development of the city, cut-slopes are made by excavating mountains. However, these cut-slopes are degraded in strength by time-deterioration phenomenon, and progressive slope failure is caused. This study developed an integrated analysis method for stability analysis and maintenance of cut-slopes in urban. The slope stability analysis was performed using the finite element model, and the progressive slope failure by time-dependent deterioration was quantified by using the strength parameters of soil applying the strength reduction factor (SRF). The displacements until the slope failure by slope stability analysis were quantified by cumulative displacement curve, velocity curve, and inverse velocity curve and, applied to the slope maintenance method. The inverse-velocity curve applied to the prediction of the time of slope failure was regressed to the 1st linear equation in the brittle material and the 3rd polynomial equation in the ductile material. This is consistent with the proposed formula of Fukuzono and also shows similar behavior to the failure case in literature. In the future, integrated analysis method should be improved through additional research. And it should be applied to cut-slope to prevent disasters.


2003 ◽  
Vol 1821 (1) ◽  
pp. 104-114
Author(s):  
Hiroyuki Matsuyama ◽  
Kenji Ogata ◽  
Kiyoyuki Amano

The discrimination model for road cut slope stability was used to assess 216 cut slope locations on the Chuo Expressway. This model ranks the failure probability of slopes by the rainfall threshold (cumulative precipitation that causes the slope to fail) to identify slopes highly prone to collapse. Because of the complexity (nonlinearity) of the relationship between the factors relating to the cut slope failure and the precipitation that triggers a failure, it has been difficult to correctly evaluate the likelihood of failure for cut slopes. The developed model has overcome that difficulty by involving the neural network as the discrimination technique. The input data included the different factors (topography, soil properties and geology, surface layer status, change in state) in the stability investigation table prepared at the time of road slope inspection, with additional information such as catchment topography. The cut slope data were prepared, referring to a variety of information encompassing the failure history for 30 years after the commencement of service, the rainfall record at the time of failure, the maximum rainfall amount ever recorded, and the data on the status of slope protection around the time of failure. As shown by the discrimination results, the model accuracy (ratio of correct answers to number of slopes evaluated) was as high as approximately 80%, which allowed accurate determination of the amounts of rainfall inducing the failure of different slopes.


Author(s):  
Hamzah Hussin ◽  
Tajul Anuar Jamaluddin ◽  
Muhammad Fadzli Deraman

Geology of Bukit Panji, Chendering, Kuala Teregganu consists of interbededmetasedimentary rocks (slate, phyllite and schists with minor quartzite) which haveexperience regional metamorphism. The age of this rock is Carboniferous. A development project which under construction in Bukit Panji, Kuala Terengganu hasenabled a landslide assessment to observe the modes of failure in moderately tocompletely weathered metasedimentary rock. Development on hillsides caused manyslope had to be cut to provide space for the infrastructure construction. From assessment analysis, a total of 21 cases of landslide failure occurred involving 17 cut slopes, and 4 cut-fill slopes. The most common type of failures is gully failures, with 9 cases represent 43% of all the observed slope failure. This was followed by 6 wedge failures, two planar and rock fall failures and one shallow sliding and toppling respectively. Cut slope failure involving moderate weathered rock mass (grade III) to the residual soil (grade VI). Relict structure was identified as the main factors controlling the failure, as well as water, natural slope-forming materials and the use of appropriate slope stabilization.


2014 ◽  
Vol 59 (1) ◽  
pp. 105-140 ◽  
Author(s):  
Alessandro Bertinetto

Die Hauptfrage, die ich in diesem Aufsatz diskutieren will, ist die folgende: Welche sind die ästhetisch-normativen Voraussetzungen für das richtige Verständnis und die richtige Evaluation von Jazz? Meine These lautet: Die Jazzästhetik ist eine Ästhetik der gelungenen Performanz. Sie ist nicht eine Ästhetik der Unvollkommenheit. Ich werde meine Argumentation in die folgenden Abschnitte gliedern. Nach der Einleitung (I.) wird in Abschnitt II. die ›These der Unvollkommenheit‹ dargestellt und in III. werden anschließend einige Argumente dagegen diskutiert. In den Abschnitten IV. und V. werden die für die Jazzästhetik wichtige Frage nach dem »Fehler« und das entscheidende Thema der Normativität untersucht. Dazu werde ich geltend machen, dass die ›These der Unvollkommenheit‹ insbesondere deswegen unbefriedigend ist, weil sie die spezifische Normativität von Jazz als Improvisationskunst missversteht. In Abschnitt VI. wird schließlich erklärt, in welchem Sinne von einer Normativität der gelungenen Performanz die Rede sein kann und warum dies für unser Verständnis von Jazz bedeutend ist. Abschließend (VII.) wird diese Idee gegen mögliche Einwände verteidigt.<br><br>In this paper I aim at discussing the aesthetic-normative conditions for the right understanding and the right evaluation of jazz. My main point is this: The aesthetics of jazz is an aesthetics of the successful performance, rather than an aesthetics of imperfection. The paper will be structured as follows. SectionI introduces the topic. SectionII presents the ›imperfection thesis‹, while III discusses some arguments against it. Sections IV and V investigate two related questions: the first is about the role of the »mistake« in jazz; the second concerns the crucial topic of normativity. At this regard I will maintain that the ›imperfection thesis‹ does not work, especially because it misunderstands the specific normativity of jazz as improvisational art. Section VI is devoted to clarifying both in which sense the idea of a normativity of the successful performance is sound and why this idea is important for understanding jazz. Finally (VII) I defend this view against possible objections.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Eva Höllmüller ◽  
Simon Geigges ◽  
Marie L. Niedermeier ◽  
Kai-Michael Kammer ◽  
Simon M. Kienle ◽  
...  

AbstractDecoding the role of histone posttranslational modifications (PTMs) is key to understand the fundamental process of epigenetic regulation. This is well studied for PTMs of core histones but not for linker histone H1 in general and its ubiquitylation in particular due to a lack of proper tools. Here, we report on the chemical synthesis of site-specifically mono-ubiquitylated H1.2 and identify its ubiquitin-dependent interactome on a proteome-wide scale. We show that site-specific ubiquitylation of H1 at position K64 modulates interactions with deubiquitylating enzymes and the deacetylase SIRT1. Moreover, it affects H1-dependent chromatosome assembly and phase separation resulting in a more open chromatosome conformation generally associated with a transcriptionally active chromatin state. In summary, we propose that site-specific ubiquitylation plays a general regulatory role for linker histone H1.


1988 ◽  
Vol 263 (36) ◽  
pp. 19662-19669
Author(s):  
T L Solomon ◽  
L R Solomon ◽  
L S Gay ◽  
P A Rubenstein
Keyword(s):  

2021 ◽  
pp. 106233
Author(s):  
Chih-Hsiang Yeh ◽  
Jia-Jyun Dong ◽  
Sara Khonevisan ◽  
C. Hsein Juang ◽  
Wen-Chao Huang ◽  
...  

Biomolecules ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 15
Author(s):  
Aishat Motolani ◽  
Matthew Martin ◽  
Mengyao Sun ◽  
Tao Lu

The nuclear factor kappa B (NF-κB) is a ubiquitous transcription factor central to inflammation and various malignant diseases in humans. The regulation of NF-κB can be influenced by a myriad of post-translational modifications (PTMs), including phosphorylation, one of the most popular PTM formats in NF-κB signaling. The regulation by phosphorylation modification is not limited to NF-κB subunits, but it also encompasses the diverse regulators of NF-κB signaling. The differential site-specific phosphorylation of NF-κB itself or some NF-κB regulators can result in dysregulated NF-κB signaling, often culminating in events that induce cancer progression and other hyper NF-κB related diseases, such as inflammation, cardiovascular diseases, diabetes, as well as neurodegenerative diseases, etc. In this review, we discuss the regulatory role of phosphorylation in NF-κB signaling and the mechanisms through which they aid cancer progression. Additionally, we highlight some of the known and novel NF-κB regulators that are frequently subjected to phosphorylation. Finally, we provide some future perspectives in terms of drug development to target kinases that regulate NF-κB signaling for cancer therapeutic purposes.


2019 ◽  
Vol 7 (4) ◽  
pp. 929-947 ◽  
Author(s):  
Michele Delchiaro ◽  
Marta Della Seta ◽  
Salvatore Martino ◽  
Maryam Dehbozorgi ◽  
Reza Nozaem

Abstract. The Seymareh landslide, detached ∼10 ka from the northeastern flank of the Kabir-kuh fold (Zagros Mts., Iran), is recognized worldwide as the largest rock slope failure (44 Gm3) ever recorded on the exposed Earth surface. Detailed studies have been performed that have described the landslide mechanism and different scenarios have been proposed for explaining the induced landscape changes. The purpose of this study is to provide still missing time constraints on the evolution of the Seymareh River valley, before and after the emplacement of the Seymareh landslide, to highlight the role of geomorphic processes both as predisposing factors and as response to the landslide debris emplacement. We used optically stimulated luminescence (OSL) to date lacustrine and fluvial terrace sediments, whose plano-altimetric distribution has been correlated to the detectable knickpoints along the Seymareh River longitudinal profile, allowing the reconstruction of the evolutionary model of the fluvial valley. We infer that the knickpoint migration along the main river and the erosion wave propagation upstream through the whole drainage network caused the stress release and the ultimate failure of the rock mass involved in the landslide. We estimated that the stress release activated a mass rock creep (MRC) process with gravity-driven deformation processes occurring over an elapsed time-to-failure value on the order of 102 kyr. We estimated also that the Seymareh damming lake persisted for ∼3500 years before starting to empty ∼6.6 ka due to lake overflow. A sedimentation rate of 10 mm yr−1 was estimated for the lacustrine deposits, which increased up to 17 mm yr−1 during the early stage of lake emptying due to the increased sediment yield from the lake tributaries. We calculated an erosion rate of 1.8 cm yr−1 since the initiation of dam breaching by the Seymareh River, which propagated through the drainage system up to the landslide source area. The evolutionary model of the Seymareh River valley can provide the necessary constraints for future stress–strain numerical modeling of the landslide slope to reproduce the MRC and demonstrate the possible role of seismic triggering in prematurely terminating the creep-controlled time-to-failure pathway for such an extremely large case study.


2006 ◽  
Vol 291 (6) ◽  
pp. F1123-F1132 ◽  
Author(s):  
James J. De Yoreo ◽  
S. Roger Qiu ◽  
John R. Hoyer

Calcium oxalate monohydrate (COM) is the primary constituent of the majority of renal stones. Osteopontin (OPN), an aspartic acid-rich urinary protein, and citrate, a much smaller molecule, are potent inhibitors of COM crystallization at levels present in normal urine. Current concepts of the role of site-specific interactions in crystallization derived from studies of biomineralization are reviewed to provide a context for understanding modulation of COM growth at a molecular level. Results from in situ atomic force microscopy (AFM) analyses of the effects of citrate and OPN on growth verified the critical role of site-specific interactions between these growth modulators and individual steps on COM crystal surfaces. Molecular modeling investigations of interactions of citrate with steps and faces on COM crystal surfaces provided links between the stereochemistry of interaction and the binding energy levels that underlie mechanisms of growth modification and changes in overall crystal morphology. The combination of in situ AFM and molecular modeling provides new knowledge that will aid rationale design of therapeutic agents for inhibition of stone formation.


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