Geotechnical Resistances of Drilled Shafts in Triassic Basin Sedimentary Rocks

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
John Turner
Keyword(s):  
Design Tool ◽  
Drilled Shafts ◽  
Late Triassic ◽  
Load Testing ◽  
Rift Basins ◽  
Base Resistance ◽  
Load Tests ◽  
The Common ◽  
Drilled Shaft Foundations

Load tests on drilled shaft foundations with rock sockets in sedimentary formations associated with various Triassic Basins in the Mid-Atlantic region show that some generalizations are possible for estimating geotechnical resistances. Axial load tests on drilled shafts in locations several hundred miles apart produce surprisingly similar results. The common feature is the geology: all of the load-tested rock sockets considered were constructed in sedimentary rock associated with one of the rift basins that developed in response to breaking apart of the supercontinent Pangaea that began during the late Triassic Period (about 220 million years ago) and coincided with opening of the Atlantic Ocean. More specifically, all of the tested rock sockets were in the ‘red bed’ facies of the rift basin sediments consisting of reddish-brown siltstone, sandstone, and shale. Each of the projects described herein and the associated load tests are described and used to illustrate fundamental principles of rock socket design and how load testing can be used as a design tool. The important role of quality construction, in combination with quality assurance through inspection and testing, is emphasized, especially as it relates to the evaluation of base resistance for rock socket design.

Innovative Method for Evaluating Drilled Shaft Foundations for St. Croix River Bridge

1998 ◽  
Vol 1633 (1) ◽  
pp. 84-93
Author(s):  
Michael W. O’Neill ◽  
Gary J. Person
Keyword(s):  
Drilled Shafts ◽  
Interface Roughness ◽  
Design Parameters ◽  
Lateral Stiffness ◽  
Test Results ◽  
Side Resistance ◽  
Major River ◽  
Load Tests ◽  
Drilled Shaft Foundations ◽  
A Site

To develop design parameters for axially loaded drilled shafts for the St. Croix River Bridge, a major river crossing at Oak Park Heights, Minnesota, load tests were conducted on half-scale sockets in the primary formation, the Franconia Sandstone, at a site on the west bank of the river. The test results were analyzed by using a procedure that considered dilatancy at the shaft-sandstone interface using the known normal, lateral stiffness of the rock, and several candidate interface roughness patterns. The normal stiffness was measured by splitting a short socket vertically with an Osterberg load cell, within the Franconia formation. The interface roughness patterns were varied until the load-deformation behavior of the axial socket test was matched. The production shafts will have larger diameters and will penetrate the formation to a shallower depth than the axial test socket. The lateral stiffness therefore was scaled to account for these effects, and the analytical method was used to determine values of side resistance that should be used for designing the production shafts.

Evaluation of uplift interpretation criteria for drilled shafts in gravelly soils

2012 ◽  
Vol 49 (1) ◽  
pp. 70-77 ◽  
Author(s):  
Yit-Jin Chen ◽  
Tsu-Hung Chu
Keyword(s):  
Drilled Shafts ◽  
Load Test ◽  
Drilled Shaft ◽  
Specific Design ◽  
Interpretation Criteria ◽  
Interpretation Criterion ◽  
Gravelly Soils ◽  
Load Tests ◽  
Drilled Shaft Foundations ◽  
Shaft Failure

Representative interpretation criteria are examined in this paper to evaluate the capacity of drilled shaft foundations under axial uplift loading in gravelly soils. A large number of uplift shaft load tests for gravelly soils are used for analysis, and the interpretation criteria are applied to these load test data to establish a consistent uplift interpretation criterion. The statistical results show that the smaller the uplift displacement, the higher the coefficient of variation. In general, the displacements required to mobilize shaft failure load in gravelly soils are larger than those in non-gravelly soils. Based on these analyses, the relative merits and interrelationships of these criteria are established. Specific design recommendations for the evaluation of uplift drilled shaft capacity are given.

Load and Resistance Factor Design, Cost, and Risk: Designing a Drilled-Shaft Load Test Program in Florida Limestone

2003 ◽  
Vol 1849 (1) ◽  
pp. 98-106 ◽  
Author(s):  
Michael C. McVay ◽  
Ralph D. Ellis ◽  
Bjorn Birgisson ◽  
Gary R. Consolazio ◽  
Sastry Putcha ◽  
...  
Keyword(s):  
Laboratory Data ◽  
Resistance Factor ◽  
Load Test ◽  
Drilled Shaft ◽  
Load Testing ◽  
Load Tests ◽  
Factor Design ◽  
Drilled Shaft Foundations ◽  
Load And Resistance Factor ◽  
The Cost

Currently there are few if any guidelines on estimating the number of load tests in the design of drilled-shaft foundations in Florida limestone. For instance, for many sites there may be a similar number of field load tests but a significantly different number of design shafts. Moreover, little if any information exists on risk or reliability versus cost of drilled-shaft foundations or on the cost of field load testing. The collection of a large database of drilled-shaft tests (more than 25 with Osterberg and Statnamic devices), in situ laboratory data, drilled-shaft construction costs, and field load testing costs for Florida limestone is reported on. From the field load tests, the average unit skin friction for various sites was found, as well as the predicted values based on the Florida Department of Transportation recommended design approach. Next, using load and resistance factor design (LRFD), the resistance (ϕ) values were found for various reliabilities (risk or probability of failure). Once the factored design loads were known (from plans), drilled-shaft lengths were estimated on the basis of the computed LRFD ϕ-values for different reliabilities (i.e., risk). From the linear length of the designed shaft as well as the expected cost per meter, a plot of total foundation cost versus reliability (risk) was generated for each site. On the basis of the latter plot, acceptable risk, and the cost of field load testing (bid and itemized), the designer can identify the cost savings of load testing and the appropriate number of tests to be performed.

On everyday academic research

2017 ◽  
pp. 98-134 ◽  
Author(s):  
J. Tirole
Keyword(s):  
Common Good ◽  
Academic Research ◽  
Research Quality ◽  
Economic Research ◽  
Relevant Research ◽  
The Common ◽  
Verification Of Models ◽  
Science And Research

In the fourth chapter of the book “The economy of the common good”, the nature of economics as a science and research practices in their theoretical and empirical aspects are discussed. The author considers the processes of modeling, empirical verification of models and evaluation of research quality. In addition, the features of economic cognition and the role of mathematics in economic research are analyzed, including the example of relevant research in game theory and information theory.

Contemplative Principles of a Non-dual Praxis: the Unmediated Practices of the Tibetan ‘Heart Essence’ (sNying thig) Tradition

2015 ◽  
Vol 31 (2) ◽  
pp. 215-240
Author(s):  
Eran Laish
Keyword(s):  
Contemplative Practice ◽  
Tibetan Buddhist ◽  
Buddhist Tradition ◽  
The Common

This article focuses on the main contemplative principles of the ‘Heart Essence’ (sNying thig), a Tibetan Buddhist tradition that is characterized by a vision of non-duality and primordial wholeness. Due to this vision, which asserts an original reality that is not divided into perceiving subject and perceived object, the ‘Heart Essence’ advocates a contemplative practice that undermines the usual intuitions of temporality and enclosed selfhood. Hence, unlike the common principles of intentional praxis, such as deliberate concentration and gradual purification, the ‘Heart Essence’ affirms four contemplative principles of non-objectiveness, openness, spontaneity and singleness. As these principles transcend intentionality, temporality, and multiplicity, they are seen to directly disclose the nature of primordial awareness, in which the meanings of knowing and being are radically transformed. Therefore, the article will also consider the role of these non-dual contemplative principles in deeply changing our understanding of being and knowing alike.

Charles de Gaulle and European Community

2020 ◽  
Vol 2020 (10-3) ◽  
pp. 70-81
Author(s):  
David Ramiro Troitino ◽  
Tanel Kerikmae ◽  
Olga Shumilo
Keyword(s):  
World War Ii ◽  
European Community ◽  
World War ◽  
Charles De Gaulle ◽  
The United Kingdom ◽  
History Of ◽  
The Common ◽  
Post War ◽  
De Gaulle

This article highlights the role of Charles de Gaulle in the history of united post-war Europe, his approaches to the internal and foreign French policies, also vetoing the membership of the United Kingdom in the European Community. The authors describe the emergence of De Gaulle as a politician, his uneasy relationship with Roosevelt and Churchill during World War II, also the roots of developing a “nationalistic” approach to regional policy after the end of the war. The article also considers the emergence of the Common Agricultural Policy (hereinafter - CAP), one of Charles de Gaulle’s biggest achievements in foreign policy, and the reasons for the Fouchet Plan defeat.

“There is such a situation that Comrade Svoboda is under pressure”. The Soviet leadership and the settlement of relations with Czechoslovakia. May 1969

2019 ◽  
pp. 512-519
Author(s):  
Teymur Dzhalilov ◽  
Nikita Pivovarov
Keyword(s):  
Central Committee ◽  
Secretary General ◽  
Political Agenda ◽  
The Political ◽  
Soviet Government ◽  
Soviet Leadership ◽  
Policy Issues ◽  
The World ◽  
The Common

The published document is a part of the working record of The Secretariat of the CPSU Central Committee on May 5, 1969. The employees of The Common Department of the CPSU Central Committee started writing such working records from the end of 1965. In contrast to the protocols, the working notes include speeches of the secretaries of the Central Committee, that allow to deeper analyze the reactions of the top party leadership, to understand their position regarding the political agenda. The peculiarity of the published document is that the Secretariat of the Central Committee did not deal with the most important foreign policy issues. It was the responsibility of the Politburo. However, it was at a meeting of the Secretariat of the Central Committee when Brezhnev raised the question of inviting G. Husák to Moscow. The latter replaced A. Dubček as the first Secretary of the Communist party of Czechoslovakia in April 1969. As follows from the document, Leonid Brezhnev tried to solve this issue at a meeting of the Politburo, but failed. However, even at the Secretariat of the Central Committee the Leonid Brezhnev’s initiative at the invitation of G. Husák was not supported. The published document reveals to us not only new facets in the mechanisms of decision-making in the CPSU Central Committee, the role of the Secretary General in this process, but also reflects the acute discussions within the Soviet government about the future of the world socialist systems.

The Science of Wisdom in a Polarized World: Knowns and Unknowns

2020 ◽  
Author(s):  
Igor Grossmann ◽  
Nic M. Weststrate ◽  
Monika Ardelt ◽  
Justin Peter Brienza ◽  
Mengxi Dong ◽  
...  
Keyword(s):  
Individual Differences ◽  
Problem Solving ◽  
Best Practices ◽  
Cognitive Sciences ◽  
Methodological Challenges ◽  
The Common ◽  
Empirical Approaches ◽  
And Training ◽  
Contextual Differences

Interest in wisdom in the cognitive sciences, psychology, and education has been paralleled by conceptual confusions about its nature and assessment. To clarify these issues and promote consensus in the field, wisdom researchers met in Toronto in July of 2019, resolving disputes through discussion. Guided by a survey of scientists who study wisdom-related constructs, we established a common wisdom model, observing that empirical approaches to wisdom converge on the morally-grounded application of metacognition to reasoning and problem-solving. After outlining the function of relevant metacognitive and moral processes, we critically evaluate existing empirical approaches to measurement and offer recommendations for best practices. In the subsequent sections, we use the common wisdom model to selectively review evidence about the role of individual differences for development and manifestation of wisdom, approaches to wisdom development and training, as well as cultural, subcultural, and social-contextual differences. We conclude by discussing wisdom’s conceptual overlap with a host of other constructs and outline unresolved conceptual and methodological challenges.

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