scholarly journals Features of ultrasonic control of mechanical properties of core rocks of geological exploration wells

2019 ◽  
Vol 109 ◽  
pp. 00115
Author(s):  
Anatolii Yalanskyi

The article discusses the features of ultrasonic operative control of the mechanical properties of rocks of geological exploration wells. The control develops in three directions: ultrasonic logging of exploration wells, the determination of the strength and elastic properties of rocks, taking into account their geological homogeneity; comprehensive monitoring of physical and mechanical properties of cores of deep and ultra-deep wells directly on the wells or core storage facilities. To control samples with untreated ends, it was proposed to use methods and means to ensure the point contact of the sensor with the surface, which allows to accurately determine the distance traveled by the waves through the sample, and taking into account the directional patterns of ultrasonic vibrations to determine the type and speed of the wave. According to the velocities of the longitudinal, shear or surface waves and the density of rocks determine the dynamic elastic parameters. The discrepancy between the actual structure of deep rock massif and seismic data is considered. With depth, the metamorphism of rocks increases. At the considered depths, the crust of rocks has a layered structure, which is due to the alternation of igneous and sedimentary rocks differing in the degree of metamorphism.

2019 ◽  
pp. 297-297
Author(s):  
Yuan Zhang ◽  
Zhijun Wan ◽  
John McLennan ◽  
Bin Gu ◽  
TA Xupeng

Determining the physical and mechanical behavior of sedimentary rocks is one of the most common challenges in deep rock mass engineering. Experiments were conducted to study the physical and mechanical properties of coal measure mudstone with scanning electron microscope, x-rays diffraction and uniaxial compression testing. The results show that temperature has a significant effect on the physical and mechanical properties of coal measure mudstone. The presence of clay minerals in the evaluated mudstone contributes to the unique characteristics seen at high temperature. The mudstone experiences obvious color changes on the surface as temperature rises. This is mostly attributed to the iron-bearing clay minerals. Internal color change is caused by thermal decomposition of kerogen associated with the clay minerals. As the major clay mineral in mudstone, kaolinite undergoes significant phase changes at high temperatures, which leads to changes in mechanical properties. From 25? to 200 ?, due to the evaporation of absorbed water from the clay minerals, the strength of the mudstone increases significantly. As the temperature continues to rise beyond this, water evaporation continues and the rock strength increases gradually from 200? to 400 ?. When the temperature reaches 400 ?, this mudstone was strengthened as a result of decomposition of the kaolinite and thermal expansion of crystalline minerals. Above 600?, dehydration of the clay minerals ends while thermal cracking initiates gradually, which results in decreasing strength.


2012 ◽  
Vol 4 (1) ◽  
pp. 1
Author(s):  
Djoko Purwanto

Timber Acacia mangium (Acacia mangium, Willd) for Furniture. The study aims to determine the mechanical and physical properties and the decorative value (color and fiber) wood of acacia mangium with using finishing materials. This type of finishing material used is ultran lasur natural dof ,ultran lasur classic teak, aqua politur clear dof, aqua politur akasia dan aqua politur cherry. After finishing the wood is stored for 3 months. Test parameters were observed, namely, physical and mechanical properties of wood, adhesion of finishing materials, color and appearance of the fiber, and timber dimensions expansion. The results showed that the mechanical physical properties of acacia wood qualified SNI. 01-0608-89 about the physical and mechanical properties of wood for furniture, air dry the moisture content from 13.78 to 14.89%, flexural strength from 509.25 to 680.50 kg/cm2, and compressive strength parallel to fiber 342.1 - 412.9 kg/cm2. Finishing the treatment process using five types of finishing materials can increase the decorative value (color and fiber) wood. Before finishing the process of acacia mangium wood has the appearance of colors and fibers and less attractive (scale scores 2-3), after finishing acacia wood fibers have the appearance of colors and interesting and very interesting (scale 4-5).Keywords: mangium wood, mechanical properties, decorative value, finishing, furniture.


2016 ◽  
Vol 13 (2) ◽  
pp. 67
Author(s):  
Engku Liyana Zafirah Engku Mohd Suhaimi ◽  
Jamil Salleh ◽  
Suzaini Abd Ghani ◽  
Mohamad Faizul Yahya ◽  
Mohd Rozi Ahmad

An investigation on the properties of Tenun Pahang fabric performances using alternative yarns was conducted. The studies were made in order to evaluate whether the Tenun Pahang fabric could be produced economically and at the same time maintain the fabric quality. Traditional Tenun Pahang fabric uses silk for both warp and weft. For this project, two alternative yarns were used which were bamboo and modal, which were a little lower in cost compared to silk. These yarns were woven with two variations, one with the yarns as weft only while maintaining the silk warp and the other with both warp and weft using the alternative yarns. Four (4) physical testings and three (3) mechanical testings conducted on the fabric samples. The fabric samples were evaluated including weight, thickness, thread density, crease recovery angle, stiffness and drapability. The results show that modal/silk and bamboo silk fabrics are comparable in terms of stiffness and drapability, hence they have the potential to replace 100% silk Tenun Pahang.


2014 ◽  
Vol 62 (1) ◽  
pp. 129-137
Author(s):  
A. Sawicki ◽  
J. Mierczyński

Abstract A basic set of experiments for the determination of mechanical properties of sands is described. This includes the determination of basic physical and mechanical properties, as conventionally applied in soil mechanics, as well as some additional experiments, which provide further information on mechanical properties of granular soils. These additional experiments allow for determination of steady state and instability lines, stress-strain relations for isotropic loading and pure shearing, and simple cyclic shearing tests. Unconventional oedometric experiments are also presented. Necessary laboratory equipment is described, which includes a triaxial apparatus equipped with local strain gauges, an oedometer capable of measuring lateral stresses and a simple cyclic shearing apparatus. The above experiments provide additional information on soil’s properties, which is useful in studying the following phenomena: pre-failure deformations of sand including cyclic loading compaction, pore-pressure generation and liquefaction, both static and caused by cyclic loadings, the effect of sand initial anisotropy and various instabilities. An important feature of the experiments described is that they make it possible to determine the initial state of sand, defined as either contractive or dilative. Experimental results for the “Gdynia” model sand are shown.


Author(s):  
Thais Helena Sydenstricker Flores-Sahagun ◽  
Kelly Priscila Agapito ◽  
ROSA MARIA JIMENEZ AMEZCUA ◽  
Felipe Jedyn

2020 ◽  
pp. 39-48
Author(s):  
B. O. Bolshakov ◽  
◽  
R. F. Galiakbarov ◽  
A. M. Smyslov ◽  
◽  
...  

The results of the research of structure and properties of a composite compact from 13 Cr – 2 Мо and BN powders depending on the concentration of boron nitride are provided. It is shown that adding boron nitride in an amount of more than 2% by weight of the charge mixture leads to the formation of extended grain boundary porosity and finely dispersed BN layers in the structure, which provides a high level of wearing properties of the material. The effect of boron nitride concentration on physical and mechanical properties is determined. It was found that the introduction of a small amount of BN (up to 2 % by weight) into the compacts leads to an increase in plasticity, bending strength, and toughness by reducing the friction forces between the metal powder particles during pressing and a more complete grain boundary diffusion process during sintering. The formation of a regulated structure-phase composition of powder compacts of 13 Cr – 2 Mо – BN when the content of boron nitride changes in them allows us to provide the specified physical and mechanical properties in a wide range. The obtained results of studies of the physical and mechanical characteristics of the developed material allow us to reasonably choose the necessary composition of the powder compact for sealing structures of the flow part of steam turbines, depending on their operating conditions.


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