Material stone-concrete – selection of composition for concrete face rockfill dams

The properties of the face zone material as a flexible foundation of the face play an extremely important role in the formation of stress-strain state of rockfill dams with reinforced concrete face. Stone-concrete, made by watering the stone backfill with cement-sand mix containing water-reducing agents is proposed to be used as such foundation in the paper. Methods of selecting the composition of the casting mixture and search results of its optimal composition by the method of factor analysis are given in this paper. The properties of stone-concrete are investigated and a dam design technique is developed based on the selection of optimal properties for the face zone of that material.

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Efficiency justification for stone-concrete face zone of rockfill dams with reinforced concrete face

E3S Web of Conferences ◽

10.1051/e3sconf/202126403022 ◽

2021 ◽

Vol 264 ◽

pp. 03022

Author(s):

Aleksandra Bestuzheva ◽

Dimitri Gadai

Keyword(s):

Reinforced Concrete ◽

Face Zone ◽

Deformation Properties ◽

The Face ◽

The Difference ◽

Stone Concrete ◽

Concrete Face

At present, over 600 dams with a reinforced concrete face are built worldwide; 7 of them are higher than 200 m. However, most of these dams have an inherent disadvantage – face cracking [1, 2, 3], caused by face deformations resulted from the difference in deformation properties of the face and downstream toe. To solve this problem, the authors consider the arrangement of a massive stone-concrete face zone.

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Search for Optimal Composition and an Investigation of Special Material for the Near-Face Zone of a Dam with Reinforced Concrete Face

Power Technology and Engineering ◽

10.1007/s10749-019-01011-1 ◽

2019 ◽

Vol 52 (6) ◽

pp. 660-668 ◽

Cited By ~ 1

Author(s):

A. S. Bestuzheva ◽

D. V. Gadai

Keyword(s):

Reinforced Concrete ◽

Optimal Composition ◽

Face Zone ◽

Concrete Face

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Impact of rockfill dam structure heterogeneity on reinforced concrete face stress-strain state

Stroitel stvo nauka i obrazovanie [Construction Science and Education] ◽

10.22227/2305-5502.2019.2.5 ◽

2019 ◽

pp. 5-5 ◽

Cited By ~ 1

Author(s):

Mikhail Sainov ◽

Igor Egorov ◽

Konstantin Pak

Keyword(s):

Reinforced Concrete ◽

Strain State ◽

Longitudinal Force ◽

Heterogeneous Structure ◽

Stress Strain ◽

Stress Strain State ◽

Rockfill Dam ◽

Deformation Properties ◽

The Face ◽

Concrete Face

Introduction. One of the main principles in designing modern ultra-high rockfill dams with reinforced concrete face is the principle of zoning rockfill of various quality in the dam body. It envisages that rockfill in the shell upper part should be compacted very carefully in order to minimize to the maximum the deflections of the reinforced concrete face. In the shell lower part it is allowed placing heterogeneous rockfill with less degree of compaction. Analysis of the results of field observations over settlements of the already constructed dams shows that this pattern of zoning may lead to considerable irregularity in distribution of rockfill deformation moduli between the upstream and the downstream parts of the dam. Numerical modeling of the existing Aguamilpa dam carried out by use arlier showed that this effect may be caused by unfavorable stress-strain state of the reinforced concrete face threatening with crack formation. Were come ended using dams of homogenous structure. However, this conclusion caused doubts of some experts. More detailed studies who see results are described in this article were conducted in order to confirm or disprove this conclusion. Materials and methods. The studies were conducted by finite element method on the example of 100 m high rockfill dam. Different alternatives of rockfill deformation properties in the shell upstream and downstream parts were considered. Results. Analysis of the results of studies confirmed the conclusions made earlier about the features of the rockfill dam reinforced concrete face stress-strain state. It was revealed that increase of rockfill deformation in the dam shell downstream part leads to appearance of additional tensile longitudinal force in the face. It increases the risk of appearance of through transversal cracks in the face. However, the heterogeneous structure of the dam shell may not have a decisive impact on stress values because the value of bending moment plays a great role. Conclusions. The results of the fulfilled study as well as modern dam construction practice show the necessity of modifying the traditional pattern of rockfill zoning in the dam body. It is necessary to provide decrease of differences in rockfill deformation of the upstream and downstream parts of the dam.

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IMPACT OF DAM ROCKFILL CREEP ON REINFORCED CONCRETE FACE STRESS-STRAIN STATE

Stroitel stvo nauka i obrazovanie [Construction Science and Education] ◽

10.22227/2305-5502.2019.1.3 ◽

2019 ◽

Author(s):

Mikhail P. Sainov ◽

Andrey Yu. Kirichenko

Keyword(s):

Reinforced Concrete ◽

Rheological Model ◽

Strain State ◽

Time Dependent ◽

Favorable Effect ◽

Stress Strain ◽

Stress Strain State ◽

Operation Period ◽

The Face ◽

Concrete Face

Introduction. Rockfill deformations are developed during long time. It is known that most intensive they are during construction period, but their increment continues also during operation period due to creep. Therefore, creep may affect the reinforced concrete face stress-strain state. Nevertheless, search for the scientific and technical information showed that the problem of creep impact on the face strength is poorly studied. Materials and methods. Studies of stress-strain state were conducted with the aid of numerical modeling by finite element method. They were carried out on the example of in-situ Toulnustouc dam, which deformations during the operation period are known by the results of field measurements. For simulation of the time-dependent dam, deformation increment process there was chosen a rheological model of soil and a technique was worked out for calculating the dam stress-strain state. At plotting the rheological model, the use was made of the simplest exponential relationship of time-dependent deformations. Results. The parameters of the rockfill model were determined by selection from condition of matching between the dam design displacements and the field data. For the considered dam, the rockfill creep has not resulted in cardinal changes in the reinforced concrete face stress-strain state. Conclusion. It was revealed that increase of the dam settlements due to creep has a favorable effect: they create additional compressive longitudinal force in the face.

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Evaluation of the Modified Naranjo Criteria for Assessing Causal Attribution of Clinical Outcome to Homeopathic Intervention as Presented in Case Reports

Homeopathy ◽

10.1055/s-0040-1701251 ◽

2020 ◽

Vol 109 (04) ◽

pp. 191-197

Author(s):

Chetna Deep Lamba ◽

Vishwa Kumar Gupta ◽

Robbert van Haselen ◽

Lex Rutten ◽

Nidhi Mahajan ◽

...

Keyword(s):

Clinical Outcome ◽

Causal Relationship ◽

Clinical Case ◽

Assessment Tool ◽

Causal Attribution ◽

Case Reports ◽

Face Validity ◽

Rater Agreement ◽

The Face ◽

Selection Of

Abstract Objectives The objective of this study was to establish the reliability and content validity of the “Modified Naranjo Criteria for Homeopathy—Causal Attribution Inventory” as a tool for attributing a causal relationship between the homeopathic intervention and outcome in clinical case reports. Methods Purposive sampling was adopted for the selection of information-rich case reports using pre-defined criteria. Eligible case reports had to fulfil a minimum of nine items of the CARE Clinical Case Reporting Guideline checklist and a minimum of three of the homeopathic HOM-CASE CARE extension items. The Modified Naranjo Criteria for Homeopathy Inventory consists of 10 domains. Inter-rater agreement in the scoring of these domains was determined by calculating the percentage agreement and kappa (κ) values. A κ greater than 0.4, indicating fair agreement between raters, in conjunction with the absence of concerns regarding the face validity, was taken to indicate the validity of a given domain. Each domain was assessed by four raters for the selected case reports. Results Sixty case reports met the inclusion criteria. Inter-rater agreement/concordance per domain was “perfect” for domains 1 (100%, κ = 1.00) and 2 (100%, κ = 1.00); “almost perfect” for domain 8 (97.5%, κ = 0.86); “substantial” for domains 3 (96.7%, κ = 0.80) and 5 (91.1%, κ = 0.70); “moderate” for domains 4 (83.3%, κ = 0.60), 7 (67.8%, κ = 0.46) and 9 (99.2%, κ = 0.50); and “fair” for domain 10 (56.1%, κ = 0.38). For domains 6A (46.7%, κ = 0.03) and 6B (50.3%, κ = 0.18), there was “slight agreement” only. Thus, the validity of the Modified Naranjo Criteria for Homeopathy tool was established for each of its domains, except for the two that pertain to direction of cure (domains 6A and 6B). Conclusion The Modified Naranjo Criteria for Homeopathy—Causal Attribution Inventory was identified as a valid tool for assessing the likelihood of a causal relationship between a homeopathic intervention and clinical outcome. Improved wordings for several criteria have been proposed for the assessment tool, under the new acronym “MONARCH”. Further assessment of two MONARCH domains is required.

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Spontaneous fracture of coal during borehole drilling as an index of burst hazard of the face zone

Soviet Mining Science ◽

10.1007/bf02498541 ◽

1977 ◽

Vol 13 (1) ◽

pp. 80-82

Author(s):

I. V. Nedashkovskii ◽

A. I. Panteleev ◽

N. I. Voronkov

Keyword(s):

Face Zone ◽

Burst Hazard ◽

Spontaneous Fracture ◽

The Face ◽

Borehole Drilling

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The construction of leadership practice: Making sense of leader competencies

Leadership ◽

10.1177/1742715021996497 ◽

2021 ◽

pp. 174271502199649

Author(s):

Dag Jansson ◽

Erik Døving ◽

Beate Elstad

Keyword(s):

Professional Practice ◽

Leadership Competencies ◽

The Self ◽

Leadership Practice ◽

Choral Conductors ◽

Making Sense ◽

Sensemaking Process ◽

The Face ◽

Depth Interviews ◽

Selection Of

The notion of leadership competencies is a much-debated issue. In this article, we propose that how the leader makes sense of his or her competencies is key to leadership practice. Specifically, we look at how leaders reconcile discrepancies between the self-perceived proficiency of various competencies and their corresponding importance. Empirically, we study leaders within the music domain – how choral conductors make sense of their competencies in the shaping of their professional practice. We investigated how choral leaders in Scandinavia ( N = 638) made sense of their competencies in the face of demands in their working situations. A mixed methodology was used, comprising a quantitative survey with qualitative comments and in-depth interviews with a selection of the respondents. The results show that when choral leaders shape their practice, they frequently face competency gaps that compel them to act or adjust their identity. The key to this sensemaking process is how they move competency elements they master to the foreground and wanting elements to the background. The concept of ‘sensemaking affordance’ is introduced to account for how various leader competency categories are negotiated to safeguard overall efficacy.

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Facial Expression Recognition Based on Multi-Features Cooperative Deep Convolutional Network

Applied Sciences ◽

10.3390/app11041428 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1428

Author(s):

Haopeng Wu ◽

Zhiying Lu ◽

Jianfeng Zhang ◽

Xin Li ◽

Mingyue Zhao ◽

...

Keyword(s):

Facial Expression ◽

Facial Expressions ◽

Facial Expression Recognition ◽

Video Data ◽

Expression Recognition ◽

Convolutional Network ◽

Facial Movements ◽

The Face ◽

Deep Convolutional Network ◽

Selection Of

This paper addresses the problem of Facial Expression Recognition (FER), focusing on unobvious facial movements. Traditional methods often cause overfitting problems or incomplete information due to insufficient data and manual selection of features. Instead, our proposed network, which is called the Multi-features Cooperative Deep Convolutional Network (MC-DCN), maintains focus on the overall feature of the face and the trend of key parts. The processing of video data is the first stage. The method of ensemble of regression trees (ERT) is used to obtain the overall contour of the face. Then, the attention model is used to pick up the parts of face that are more susceptible to expressions. Under the combined effect of these two methods, the image which can be called a local feature map is obtained. After that, the video data are sent to MC-DCN, containing parallel sub-networks. While the overall spatiotemporal characteristics of facial expressions are obtained through the sequence of images, the selection of keys parts can better learn the changes in facial expressions brought about by subtle facial movements. By combining local features and global features, the proposed method can acquire more information, leading to better performance. The experimental results show that MC-DCN can achieve recognition rates of 95%, 78.6% and 78.3% on the three datasets SAVEE, MMI, and edited GEMEP, respectively.

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A Clinical Study to Correlate the Facial Form and Maxillary Central Incisor Tooth Form in Males and Females of Davangere Population

Dental Journal of Advance Studies ◽

10.1055/s-0038-1672063 ◽

2016 ◽

Vol 04 (03) ◽

pp. 156-164

Author(s):

Deepak Bansal ◽

Shruti Sharma ◽

Manjit Kumar ◽

Amrit Khosla

Keyword(s):

Facial Appearance ◽

Central Incisor ◽

Incisor Tooth ◽

Maxillary Central Incisor ◽

Anterior Teeth ◽

The Face ◽

Tooth Form ◽

Males And Females ◽

Selection Of ◽

Made In

AbstractAn altered facial appearance is more difficult to face, than problems related to ill-fitting denture or eating. The selection of maxillary anterior teeth for complete denture has long posed problem in clinical practice and a controversy about the best method to employ still exists. An attempt is made in the present study to clinically correlate the face form with maxillary central incisor tooth form in males and females of Davangere population. In 1914, Leon William's projected the “the form method” where he classified facial forms as square, tapering, and ovoid. Maxillary central incisors were selected according to the facial forms.Of total 100 subjects four different tooth forms and face forms were evaluated. They are: square, ovoid, square-tapered, tapered. No significant correlation existed between face form in male and females. Females exhibited greater correlation between face forms and inverted tooth form but that correlation is not sufficient to serve as a guide for selection of anterior teeth.

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