Statistics of Atterberg limit values of some pure kaolinitic clays

2021 ◽  
pp. 1-16
Author(s):  
Giovanni Spagnoli ◽  
Satoru Shimobe
Keyword(s):  
Atterberg Limit ◽  
Limit Values

A plasticity chart as an aid to the identification and assessment of industrial clays

Clay Minerals ◽  
1971 ◽  
Vol 9 (1) ◽  
pp. 1-17 ◽  
Author(s):  
J. A. Bain
Keyword(s):  
Physical Properties ◽  
Clay Minerals ◽  
Plasticity Index ◽  
Plastic Limit ◽  
Atterberg Limit ◽  
Plastic Properties ◽  
Limit Values ◽  
Advantages And Disadvantages ◽  
Identification Chart

AbstractThe plastic properties of clays are sufficiently variable to offer a simple but practical aid to identification. This can be done by using their Atterberg 'plastic limit' and 'plasticity index' values as parameters for an identification chart. The advantages and disadvantages of the technique are discussed, and results for a wide variety of clay minerals, particularly industrial clay types, are illustrated. A brief summary is also given of the effect of non-clay impurities, and reference is made to the correlation of Atterberg limit values with other physical properties of clays.

scholarly journals LIQUID LIMIT VALUES OBTAINED BY DIFFERENT TESTING METHODS

2017 ◽  
Vol 50 (2) ◽  
pp. 778 ◽  
Author(s):  
G. Kollaros
Keyword(s):  
Linear Regression Analysis ◽  
Correlation Coefficients ◽  
Liquid Limit ◽  
Natural Soil ◽  
Cone Penetrometer ◽  
Atterberg Limit ◽  
Limit Values ◽  
Soil Material ◽  
Stabilized Soil

Specifications in European countries include a variety of methods for determining the liquid limit based on Casagrande type devices and on the fall cone penetrometer. The results of a comparative study of the liquid limits determined using these two fall-cone methods are presented for lime stabilized soil. Soil material sampled in the area of Evros Regional Unit has been stabilized with lime in order to enhance its engineering characteristics. The soil and the soil-lime mixtures subjected in Atterberg limit testing. The liquid limit values were correlated through a linear regression analysis with the rest of the consistency limits of both the natural soil and its mixtures with various lime contents. The correlation coefficients in all cases were high, with those referring to results obtained by the Casagrande method to be dominant. The comparison of liquid limit values determined by either method showed that there is a systematically good correlation between them, with the decrease rate in function of the lime content in the mixture to be more intense in the case of the drop-cone procedure. There is a need for a universal specification for the determination of the consistency limits. 

scholarly journals Perbaikan Subgrade pada Jalan Kampung Keramat di Kota Pangkalpinang dengan Menggunakan Kapur Padam Sebagai Bahan Stabilisasi Tanah

2020 ◽  
Vol 17 (1) ◽  
pp. 22-30
Author(s):  
Ferra Fahriani ◽  
Desy Yovianti ◽  
Eko Saputra ◽  
Merley Misriani
Keyword(s):  
Specific Gravity ◽  
Soil Stabilization ◽  
Clay Soil ◽  
Liquid Limit ◽  
Soil Conditions ◽  
Atterberg Limit ◽  
Limit Values ◽  
The Road ◽  
On The Road ◽  
Soil Gradation

Soil is the main support in a construction. Unstable soil conditions, especially in the subgrade can cause damage to the road. Based on the results of a direct survey in the field, it was found that the condition of the Jalan Kampung Keramat in Pangkalpinang City was damaged. This might be caused by the condition of the subgrade on the road which is unstable and the subgrade is categorised as clay soil type. This study aims to improve the subgrade on Jalan Kampung Keramat in Pangkalpinang City by using limestone as a soil stabilization material. This study used an experimental method in the laboratory by making mixture between clay soil and limestone with four different variations in the percentage of limestone, namely 0%, 3%, 5%, 7%. There are four parameters of the mixed characteristics that are tested and analysed, namely: the Atterberg limit, specific gravity, soil gradation and CBR value. The results show that the Atterberg limit values ​​(liquid limit-LL and plasticity index-IP) and specific gravity tend to decrease with increasing percentage of limestone extinguished. However, the plastic limit value (PL) shows the opposite tendency, i.e. it increases with the decreasing percentage of limestone. The specific gravity values ​​obtained based on the percentage of lime outages (0%, 3%, 5%, 7%) are 2.63, 2.61, 2.60, and 2.58, respectively. In addition, the addition of limestone causes changes in soil gradation, namely the addition of retained fraction # No.200 and the reduction of passed fraction # No.200. The Addition of limestone can increase the CBR value of the soil, where the addition of 7% of limestone produces the highest CBR value (21.3%) compared to 5% limestone (15.7%), 3% limestone (13.4%) and 0% limestone (11.2%). Therefore, using limestone can improve quality of subgrade, which can be seen from the value of CBR obtained.  

Study of the process of forming a hole for a thread at manufacturing a high nut

2020 ◽  
Vol 76 (8) ◽  
pp. 841-846
Author(s):  
I. G. Shubin ◽  
A. A. Kurkin
Keyword(s):  
Metal Flow ◽  
Nonlinear Dependence ◽  
Geometrical Parameters ◽  
Relative Height ◽  
Forming Process ◽  
Normal Height ◽  
Accuracy Class ◽  
Limit Values ◽  
Program Complex ◽  
Class B

During manufacturing nuts of increased height, a problem of obtaining correct cylindrical form of the hole for thread and overall geometrical parameters arises. To solve the problem it is necessary to know regularity of the blank forming process. Results of the study of a technological process of high hexahedral nuts forming presented. The nuts were M18 of 22 mm height, M16 of 19 mm height and M12 of normal height 10 mm according to GOST 5915–70, accuracy class B, steel grade 10 according to GOST 10702–78. The volumetric stamping was accomplished at the five-position automatic presses of АА1822 type. It was determined, that unevenness of the metal flow in the process of plastic deformation of blanks of increased height nuts was caused by different stress conditions by their sections. To simulate the mode of deformation, the program complex QForm-3D was chosen. The complex ensured to forecast with necessary accuracy the metal flow in a blank, as well as to define the deformation force and arising stress in the working instrument. The simulation showed the presence of regularity between preliminary formed buffle and deviation of dimensions and form of a blank wall after its finishing piercing, which can be expressed by a nonlinear dependence. The limit values of the relative height of the buffle С/D = 0.56–0.588 defined, exceeding which will result in rejection of the finished product. Accounting the limit values of the relative height of the buffle will enable to correct a mode of technological operations and technological instruments at stamping of high hexahedral nuts.

The limit state of concrete and reinforced concrete rods at complex and longitudinal-transverse bending

2020 ◽  
pp. 60-73
Author(s):  
Yu V Nemirovskii ◽  
S V Tikhonov
Keyword(s):  
General Solution ◽  
Least Squares ◽  
Nonlinear Differential Equations ◽  
Limit State ◽  
Algebraic Equations ◽  
Method Of Least Squares ◽  
Elasticity Limit ◽  
Limit Values ◽  
Symbolic Calculations ◽  
Deformation Diagrams

The work considers rods with a constant cross-section. The deformation law of each layer of the rod is adopted as an approximation by a polynomial of the second order. The method of determining the coefficients of the indicated polynomial and the limit deformations under compression and tension of the material of each layer is described with the presence of three traditional characteristics: modulus of elasticity, limit stresses at compression and tension. On the basis of deformation diagrams of the concrete grades B10, B30, B50 under tension and compression, these coefficients are determined by the method of least squares. The deformation diagrams of these concrete grades are compared on the basis of the approximations obtained by the limit values and the method of least squares, and it is found that these diagrams approximate quite well the real deformation diagrams at deformations close to the limit. The main problem in this work is to determine if the rod is able withstand the applied loads, before intensive cracking processes in concrete. So as a criterion of the conditional limit state this work adopts the maximum permissible deformation value under tension or compression corresponding to the points of transition to a falling branch on the deformation diagram level in one or more layers of the rod. The Kirchhoff-Lyav classical kinematic hypotheses are assumed to be valid for the rod deformation. The cases of statically determinable and statically indeterminable problems of bend of the rod are considered. It is shown that in the case of statically determinable loadings, the general solution of the problem comes to solving a system of three nonlinear algebraic equations which roots can be obtained with the necessary accuracy using the well-developed methods of computational mathematics. The general solution of the problem for statically indeterminable problems is reduced to obtaining a solution to a system of three nonlinear differential equations for three functions - deformation and curvatures. The Bubnov-Galerkin method is used to approximate the solution of this equation on the segment along the length of the rod, and specific examples of its application to the Maple system of symbolic calculations are considered.

Study of liquid limit values determined by Casagrande cup and Cone penetrometer test for different clays

Geotecnia ◽  
2017 ◽  
Vol 140 ◽  
pp. 63-72 ◽  
Author(s):  
Kátia Vanessa Bicalho ◽  
◽  
Josiane Gramelich ◽  
Camila Santos Cunha ◽  
Rogério Sarmento Junior ◽  
...  
Keyword(s):  
Liquid Limit ◽  
Cone Penetrometer ◽  
Limit Values

New aspects of power grid facilities personnel workplaces electromagnetic environment

2020 ◽  
Vol 60 (9) ◽  
pp. 569-574
Author(s):  
Nina B. Rubtsova ◽  
Sergey Yu. Perov ◽  
Olga V. Belaya ◽  
Tatiana A. Konshina
Keyword(s):  
Transmission Lines ◽  
Power Transmission ◽  
Power Grid ◽  
Spectral Characteristics ◽  
Ground Level ◽  
Frequency Characteristics ◽  
Frequency Range ◽  
Electromagnetic Environment ◽  
Limit Values ◽  
Special Assessment

Introduction. Electromagnetic safety of power grid facilities staff requires the exclusion of electromagnetic fields (EMF) harmful effects. EMF is evaluated by 50 Hz electric and magnetic fields (EF and MF) values in the framework of working conditions special assessment, and very rarely the analysis of the electromagnetic environment (EME) is carried out in depth. The aim of the study - EME hygienic assessment of power grid EHV facilities personnel workplace with adequate 50 Hz EF and MF levels evaluation as well as the analysis of EF and MF in the frequency range from 5 Hz to 500 Hz amplitude-frequency characteristics. Materials and methods. 50 Hz EF and MF values assessment was carried out on open switchgears (S) of substations and within sanitary breaks of 500 and 750 kV overhead power transmission lines (OTL). Measurements along to OTL trasses was performed using matrix-based method. Measurements and analysis of EF and MF values in 5-500 Hz frequency range amplitude-frequency characteristics were performed in the territory of 500 and 750 kV S. Results. Power frequency 50 Hz measurements results at 500 and 750 kV S ground-level personnel workplaces showed the presence of an excess of permissible limit values by EF intensity and the absence of an excess by MF. The measured EF values within 500 and 750 kV OTL sanitary gaps require limiting the working time of linemen due to the excess of the hygienic norms for full work shift, while the MP levels were almost completely within the standard values for persons not occupationally connected with electrical installations maintenance. MF and EE frequency range from 50 Hz to 500 Hz spectral characteristics analysis showed that 3rd harmonic percentage does not exceed 2.5% for EF and 6% for MF of the main level, the level of the 5th harmonic does not exceed 1% for EF and 3.5% for MF, the level of the 7th harmonic does not exceed 0.2% for EF and 0.8% for MF. These data show despite its low levels the contribution of MF different harmonics in a possible adverse impact on humane than EF corresponding harmonics. Conclusions. There was the confirmation of the previously justified use of the "matrix" scheme for of EF and MF values measurement along OTL routes. The relevance of to EF and MF all frequency components expos ure assessing possible health risk in extremely high voltage S territories and under OTL, based on international recommendations due to the lack of sanitary regulations in the Russian Federation for >50 Hz-30 kHz EF and MF, is shown.

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