1,720,994 research outputs found
含软弱夹层的强风化泥岩强度及破坏模式试验研究
No full textIn order to investigate the effects of weak interlayer on slope instability, theoretical and experimental studies on the strength and the failure mode of rock containing weak interlayer were conducted. Three types of triaxial specimens of strongly weathered mudstone, muddied interlayer, and mudstone with the weak interlayer were prepared by using the core specimens of a slope borehole, and the triaxial consolidation undrained shear tests were conducted, respectively. Combined with the theoretical analysis, the strengths and failure modes of the strongly weathered mudstone, the muddied interlayer and the mudstone with weak interlayer were studied, and the influence laws of the interlayer angle and the confining pressure on the strengths and failure modes of specimens were revealed. The results show that the stress-strain curves of the strongly weathered mudstone and the muddied interlayer are strain-softening type and strain-hardening type, respectively. There exists a critical inclination angle range for specimens containing the weak interlayer. When the interlayer angle is within the range, the failure surface occurs in the weak interlayer. When the interlayer angle is outside the range, specimens undergo global shear damage. When the confining pressure exceeds 0.4 MPa, the confining pressure has no effect on the failure mode of specimens containing the weak interlayer.</p
Study on visualization and failure mode of model test of rock-socketed pile in soft rock
No full textComputed tomography (CT) technology is a kind of nondestructive image reconstruction technology. CT visualization technology is introduced into the physical model test of a single pile, which can visualize a rock-socketed pile in soft rock under different pile top loads. In this article, the visualization process of a model test of a rock-socketed pile in soft rock is carried out by medical CT. The implementation procedure, the composition of the device, and the technical requirements of the test equipment, as well as the CT scanning operation of nondestructive visualization technique of the single pile model test, are introduced in detail. The influence of a marked layer setting, side wall effect, size of the model cylinder, and model pile on the visualization effect of a single pile model test is discussed. The feasibility and reliability of the model test visualization technology of a rock-socketed pile in soft rock are demonstrated by examples, and the failure mode of rock-socketed pile in soft rock is intuitively revealed to be the spherical cavity expansion mode of the pile end.</p
su-Based Shaft Friction Design Method and Evaluation for Pipe Pile
No full textThe shaft friction in clay is essential to bearing capacity of pipe piles. Reasonable selection of design methods and parameters is very important for offshore piles. This paper focuses on the current popular vertical load design methods based on undrained strength for pipe piles, especially for offshore piles. Based on the database, the accuracy and reliability of various pile design methods based on undrained strength su in clay were reviewed. The small-scale model tests were conducted to evaluate su-based methods. For the shortcomings of small-diameter piles in the database, a field test of full-scale offshore pile was carried out and analysed. By comparing the calculated and the measured capacity for each method, the reliability of various design methods is evaluated for large-diameter piles. For the design methods based on undrained strength, it demonstrates the importance and reliability of the determination of undrained strength parameters. In view of the vertical loading conditions of offshore large-diameter steel pipe piles, reasonable suggestions for design methods and parameters determination are given
Vertical bearing characteristics of rock-socketed pile in a synthetic soft rock
No full textUsing the model test technology of the rock-socketed pile in soft rock in consideration of the influence of the overburden, the physical model test with different overburden pressure and different rock-socketed depth is carried out. The vertical bearing mechanism and law of the rock-socketed pile in soft rock are analysed through the results of axial force distribution, shaft resistance distribution, load sharing ratio of shaft resistance and base resistance, shaft resistance relationship between shaft resistance and displacement, and relationship between base resistance and displacement, etc. Based on the accurate qualitative analysis of indoor model test results, and combined with the measured data and engineering experience at home and abroad, the vertical bearing characteristics of the rock-socketed pile in soft rock are comprehensively interpreted, and the vertical bearing mechanism and its influencing factors of the rock-socketed pile in soft rock are revealed.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Prediction of normalized modulus reduction curve based on limited measurement data
No full textThe precision and reliability of the normalized modulus reduction curve in laboratory tests can be significantly compromised by the scarcity of specimens as well as variations among them, which can further impact the accuracy of seismic response analysis. In this paper, a Bayesian updating framework is proposed to predict the normalized modulus reduction curve with limited measurement data. Different prior distributions and measurement errors are investigated. Results show that the proposed technique is effective and efficient in handling limited data, reducing the uncertainty of variables through measurements, and improving the accuracy of the normalized modulus reduction curve with the acquisition of more measurements
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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