scholarly journals Dam Foundation Treatment: High Stress Watetightness

2020 ◽  
Vol 150 ◽  
pp. 01002
Author(s):  
Maha Ben Tahar ◽  
Lahcen Bahi ◽  
Latifa Ouadif
Keyword(s):  
Statistical Study ◽  
High Stress ◽  
Grout Curtain ◽  
Dual Function ◽  
Dam Foundation ◽  
Karst Environment ◽  
Foundation Treatment ◽  
Overall Stability ◽  
Dam Site

By its dual function of consolidation and sealing, injection treatment is the most appropriate process to solve the majority of problems in the most diverse soils. Concerning a foundation, the use of this treatment makes it possible to reduce or eliminate karst risks by taking into account the geological implications of each region. However, its effectiveness is difficult to measure, especially when it comes to the treatment of a dam site where the waterthigtness of the foundation is essential for overall stability. A control of the parameters that regulate the injectability of the karst as well as a good knowledge of the karst environment allows the correct evaluation of the nature of the products and the methods of implementation of the grout curtain guaranteeing the safety of the structure. It is from this perspective that a statistical study of karst anomalies was carried out on the foundation of El Ghrass dam in order to define an adequate distribution of these karsts, which is essential for the determination of the pattern of injection (drilling spacing, alignments) necessary for the preparation of the quantities of the injection market.

scholarly journals Torrential Flood Water Management: Rainwater Harvesting through Relation Based Dam Suitability Analysis and Quantification of Erosion Potential

2021 ◽  
Vol 10 (1) ◽  
pp. 27
Author(s):  
Bilal Ahmad Munir ◽  
Sajid Rashid Ahmad ◽  
Raja Rehan
Keyword(s):  
Sediment Yield ◽  
Soil Loss ◽  
Rainwater Harvesting ◽  
Suitability Analysis ◽  
Valley Bottom ◽  
The North ◽  
Roughness Index ◽  
Dam Site ◽  
Very High

In this study, a relation-based dam suitability analysis (RDSA) technique is developed to identify the most suitable sites for dams. The methodology focused on a group of the most important parameters/indicators (stream order, terrain roughness index, slope, multiresolution valley bottom flatness index, closed depression, valley depth, and downslope gradient difference) and their relation to the dam wall and reservoir suitability. Quantitative assessment results in an elevation-area-capacity (EAC) curve substantiating the capacity determination of selected sites. The methodology also incorporates the estimation of soil erosion (SE) using the Revised Universal Soil Loss Equation (RUSLE) model and sediment yield at the selected dam sites. The RDSA technique identifies two suitable dam sites (A and B) with a maximum collective capacity of approximately 1202 million m3. The RDSA technique was validated with the existing dam, Gomal-Zam, in the north of Sanghar catchment, where RDSA classified the Gomal-Zam Dam in a very high suitability class. The SE estimates show an average of 75 t-ha−1y−1 of soil loss occurs in the study area. The result shows approximately 298,073 and 318,000 tons of annual average sediment yield (SY) will feed the dam A and B respectively. The SE-based sediment yield substantiates the approximate life of Dam-A and Dam-B to be 87 and 90 years, respectively. The approach is dynamic and can be applied for any other location globally for dam site selection and SE estimation.

Molar Absorptivity Values for Aflatoxins and Justification for Their Use as Criteria of Purity of Analytical Standards

1970 ◽  
Vol 53 (1) ◽  
pp. 96-101 ◽  
Author(s):  
J V Rodricks ◽  
L Stoloff ◽  
W A Pons ◽  
J A Robertson ◽  
L A Goldblatt
Keyword(s):  
Thin Layer ◽  
Statistical Study ◽  
Molar Absorptivity ◽  
Confidence Limits ◽  
Components Of Variance ◽  
Significant Difference ◽  
Single Determination ◽  
Comparison Measurements ◽  
Analytical Standards

Abstract Measurements of molar absorptivities in methanol were carried out by two laboratories on samples of anatoxins Bi and Gi prepared and purified independently in four laboratories and on samples of aflatoxins B2 and G2 prepared and purified independently in three laboratories. Molar absorptivities of pure aflatoxins Bi, B2, G1, and G2 in benzene-acetonitrile (98 + 2) were determined at two laboratories. With the exception of aflatoxin G2, no significant difference between aflatoxin samples could be demonstrated. Molar absorptivity values and absorbance ratios for each aflatoxin, based on these data, are given. Statistical 95% confidence limits were established for a single determination of molar absorptivity. A statistical study was made of the components of variance which contribute to the accuracy of the determination of molar absorptivity. A comparison of the fluorescence intensities of spots of various aflatoxin preparations, developed on silica gel-coated thin layer plates, with the amount of aflatoxin in each spotting solution as determined by absorbance measurements, demonstrated the validity of using absorbance and fluorescence comparison measurements for aflatoxin quantitation.

High Strength Combined Support Technology in Deep High Stress Soft Rock Roadway

2012 ◽  
Vol 524-527 ◽  
pp. 598-603
Author(s):  
Nian Jie Ma ◽  
Zhi Qiang Zhao ◽  
Hua Zhao ◽  
Li Shuai Jiang
Keyword(s):  
High Stress ◽  
Soft Rock ◽  
High Strength ◽  
Parameter Determination ◽  
Test Results ◽  
Actual Measurement ◽  
Computer Numerical Simulation ◽  
Soft Rock Roadway ◽  
Rock Roadway

In order to solve the serious damage and repeat revision problem of high stress soft rock roadway in deep -950 level of Tangshan coal mine, based on the theory of the maximum stress level, together with the actual measurement of geostress and the laboratory mechanical parameters of rock-core and computer numerical simulation, the high strength combined support technology and supporting parameters are determined and the engineering test has been done. The engineering test results show that the parameter determination of high strength combined support technology, which based on the actual measurement of geostress, can effective solve the support issue of high stress soft rock roadway and provide useful experience for similar engineering problems.

Comparison of Permeability and Groutability of Ostur Dam Site Rock Mass for Grout Curtain Design

2012 ◽  
Vol 46 (2) ◽  
pp. 341-357 ◽  
Author(s):  
S. M. Sadeghiyeh ◽  
M. Hashemi ◽  
R. Ajalloeian
Keyword(s):  
Rock Mass ◽  
Grout Curtain ◽  
Dam Site

scholarly journals DETERMINATION OF THE FREQUENCY OF STAB-CUT DAMAGES OF INTERNAL ORGANS AND THE CONDITIONS OF THEIR CAUSES

2020 ◽  
Author(s):  
Aleksey A. Devyaterikov
Keyword(s):  
Statistical Study ◽  
The Body ◽  
Average Depth ◽  
Internal Organs ◽  
Medical Examinations

Aim. Determination of the frequency of stab-cut damages of internal organs and the conditions of their causes. Material and methods. The article presents the results of a retrospective statistical study of the conclusions of the forensic medical examinations of the corpses of the Khabarovsk State Forensic Bureau for the period from 2014-2018. Results. The frequency of injury with sharp objects, the most commonly damaged internal organs during stab-cut wounds and the average depth of the wound channels both in the body as a whole and separately for internal organs were established in the course of the study.

scholarly journals Liquefaction Susceptibility of an Earth Dam Foundation: A Case Study 

2021 ◽  
Author(s):  
Hatem karoui ◽  
Mounir Bouassida
Keyword(s):  
Ground Surface ◽  
Standard Penetration Test ◽  
Earth Dam ◽  
Sand Layer ◽  
Dam Foundation ◽  
Liquefaction Susceptibility ◽  
Numerical Predictions ◽  
Earth Embankment ◽  
Heterogeneous Foundation

Abstract Sidi El Barrak earth dam is a compacted earth embankment of height 28 m built in 1999 on a heterogeneous foundation with strong dominance of sandy formations. The dam foundation was subjected to several tests to predict its behavior against the liquefaction risk. Standard penetration test (SPT) results served to evaluate the liquefaction risk in an earthquake occurrence. This article, firstly, presents an interpretation of data collected from SPT tests. Determination of liquefaction risk resulted from the empirical methods proposed by Seed & Idriss, (1985) and Idriss & Boulanger, (2008). Obtained results by those methods showed that, for different earthquake magnitudes equal to 5.25, 6 and 6.75, the risk of liquefaction exists in the pure sand layer located between the ground surface and 15 m depth of the foundation of the earth dam. An UBC3D-PLM constitutive model was adopted for studying the numerical response of sand layer subjected to an earthquake of acceleration equal 0.2 g to estimate its liquefaction risk. Recorded SPT data and laboratory tests results served for the determination of geotechnical parameters of this model. From numerical predictions it revealed that the liquefaction risk is greater for an earthquake characterized by an acceleration equal 0.2g.

scholarly journals A comparative study of beam design curves against lateral torsional buckling using AISC, EC and SP

2019 ◽  
Vol 15 (1) ◽  
pp. 25-32 ◽  
Author(s):  
Vera V Galishnikova ◽  
Tesfaldet H Gebre
Keyword(s):  
Steel Structures ◽  
Reduction Factor ◽  
Steel Beams ◽  
Steel Beam ◽  
Lateral Torsional Buckling ◽  
Torsional Buckling ◽  
Vertical Loading ◽  
Beam Design ◽  
Overall Stability

Introduction. Structural stability is an essential part of design process for steel structures and checking the overall stability is very important for the determination of the optimum steel beams section. Lateral torsional buckling (LTB) normally associated with beams subject to vertical loading, buckling out of the plane of the applied loads and it is a primary consideration in the design of steel structures, consequently it may reduce the load currying capacity. Methods. There are several national codes to verify the steel beam against LTB. All specifications have different approach for the treatment of LTB and this paper is concentrated on three different methods: America Institute of Steel Construction (AISC), Eurocode (EC) and Russian Code (SP). The attention is focused to the methods of developing LTB curves and their characteristics. Results. AISC specification identifies three regimes of buckling depending on the unbraced length of the member ( Lb ). However, EC and SP utilize a reduction factor (χ LT ) to treat lateral torsional buckling problem. In general, flexural capacities according to AISC are higher than those of EC and SP for non-compact sections.

Diagnostic tool for the diagnosis of physiological and pathological conditions of the uterus in cows postpartum

2021 ◽  
Vol 49 (04) ◽  
pp. 229-233
Author(s):  
Isatay Jakupov ◽  
Zhanargul Karabayeva ◽  
Aida Abultdinova
Keyword(s):  
Dual Function ◽  
New Device ◽  
Black And White ◽  
Pathological Alteration ◽  
Uterine Involution ◽  
Pathological Conditions ◽  
New Instrument ◽  
Early Diagnose ◽  
Cattle Husbandry

Abstract Objective An important task of veterinarians in cattle husbandry is the early diagnosis of postpartum complications that can lead to infertility. The aim of the study was the evaluation of a new device to distinguish between physiological and pathological conditions of the uterus based on the determination of the time of uterine involution and the physicochemical properties of the vaginal discharge (lochia) during the first weeks after parturition. Material and methods A total of 173 black-and-white Holstein-Friesian dairy cows were examined for any pathological alteration of the uterine involution on days 1–2, 6–8, 11–14 postpartum and, in case of pathological findings, additionally on days 18–22, 23–27 and 28–30 after parturition. In addition to the standard examination a newly developed hand-held instrument (“Metrastatum”) was used to differentiate between physiological and pathological uterine involution. It allows determination of the distance between the cervix and vulva (DCV) and simultaneous collection of lochial secretions. Results The best time to use the new instrument was 10–16 days postpartum. In healthy cows without disturbed puerperium, the average DCV was 25.7 cm (± 0.8 cm) in this phase. This distance decreased by 12.5 ± 0.3 cm compared to the first days. In contrast, in cows with postpartum problems, the DCV was significantly greater at (31 ± 0.7 cm) (p < 0.001). In these animals, the AGV was reduced only by an average of 8.4 ± 0.6 cm when compared to the first days. The mucus obtained with the dome-shaped rubber funnel of the instrument also differed in the cows of the 2 groups. In healthy cows without puerperal problems, the lochia were thick, colorless, transparent and sometimes cloudy. In case of puerperal disorders, the discharge was thin, light red to reddish brown, contained flakes and had a nasty odor depending on the form of the inflammation. Conclusion The dual function of device helps to early diagnose puerperal disorders in cows and to select healthy animals for reproduction and sick cows for treatment depending on the form of uterine inflammation.

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