Effect of tensile stress concentration around magma chambers on intrusion and extrusion frequencies

1988 ◽  
Vol 35 (3) ◽  
pp. 179-194 ◽  
Author(s):  
Agust Gudmundsson
2016 ◽  
Vol 368 ◽  
pp. 121-125
Author(s):  
Pavel Kejzlar ◽  
Tomáš Pilvousek ◽  
Michal Tregler

The present work deals with determination of the cause of crack occurring in a part of car body manufactured from deep-drawing sheet. UHR-SEM, EDS, EBSD and measurement of microhardness were used for evaluation of the structure, local deformation and crack formation mechanism. A material analysis discovered foreign particles in the material. These particles were identified as MgAl2O4 with BCC lattice. The occurrence of these hard particles led to local stress concentration, decrease in mechanical strength and sheet breach due to tensile stress during deformation.


1991 ◽  
Vol 44 (5) ◽  
pp. 545 ◽  
Author(s):  
RE Collins ◽  
AC Fischer-Cripps

Flat evacuated glazing consists of two plane sheets of glass separated by a narrow evacuated space. These structures must incorporate an array of support pillars in order to maintain the separation of the glass plates under the influence of atmospheric pressure forces. A design procedure is outlined for determining the dimensions of this pillar array. Two important constraints in the design process are the mechanical tensile stress on the outside of the glass plates near the pillar, and the thermal conductance through the array of support pillars. A third constraint arises because of stress concentration near the pillars on the inside of the window. Evacuated windows having usefully low values of thermal conductance through the pillar array and tolerably small levels of exterior tensile stress can only be produced if large stresses exist on the inside of the structure in the region of the glass plates near the support pillars. The implications of these stresses are discussed. It is concluded that it is possible to design a pillar array for which the localised tensile stresses and overall thermal conductance have usefully small values.


2007 ◽  
Vol 44 (1) ◽  
pp. 194-200 ◽  
Author(s):  
Kunigal N. Shivakumar ◽  
Anil Bhargava ◽  
James C. Newman

2011 ◽  
Vol 94-96 ◽  
pp. 1545-1548
Author(s):  
Ying Min Li ◽  
Lu Wang ◽  
Li Ping Liu

Based on the test and numerical analysis, the paper studied the constructional reinforcement of blast furnace foundation under the influence of concrete hydration and top temperature. The results indicate that constructional reinforcement should be thinner and have a small spacing. Stress concentration always appears around the corner and constraints of blast furnace foundation, where should be strengthened with constructional reinforcements. In order to prevent cracks caused by internal tensile stress during concrete hardening, it is necessary to place temperature reinforcement inside the foundation. Temperature effect should be considered at the circular area on top of blast furnace foundation and should be strengthened with constructional reinforcements.


1974 ◽  
Vol 9 (2) ◽  
pp. 118-129 ◽  
Author(s):  
D Budney ◽  
N L Svensson

This investigation deals with the stress and strain distribution in a large plate containing a reinforced circular hole when loaded monotonically in uniaxial tension beyond the elastic range. The hole is reinforced with a cylindrical member which is symmetrical with respect to the plate to which it is continuously joined. Consideration is given to various degrees of plastic deformation of plate and reinforcement corresponding to various uniaxial tension loads. Whole-field analyses of the reinforcement in cylindrical co-ordinates and of the plate in plane polar co-ordinates are obtained by the finite-difference method in which the governing equilibrium equations are expressed in terms of displacements and plastic strains. Deformation theory of plasticity is employed. Limitations of the ‘compact’ reinforcement assumption result from the subsequent whole-field investigation. Results are obtained for material of a specific stress-strain curve so that strain-gauge results could be compared with the strains predicted by the finite-difference analysis. It is demonstrated that the compact reinforcement is adequate for analysis of the plate, but for a very significant range of reinforcement geometry it neglects a more serious stress concentration in the reinforcement. For the whole-field analysis, prediction of first yield is made for four critical points: tensile-stress concentration in the plate; tensile-stress concentration in the reinforcement; and shear-stress concentrations in both plate and reinforcement at their joint.


2012 ◽  
Vol 5 (2) ◽  
pp. 158 ◽  
Author(s):  
Feras Darwish ◽  
Lubna Al Nasser ◽  
Omar Al Araidah

2008 ◽  
Vol 575-578 ◽  
pp. 649-653
Author(s):  
Jun Min Li ◽  
Fu Rong Chen

Aiming at the radiator with tube-to-plate structure applied usually in aeroplane, a two-dimensional model for finite element analysis was established in this work. By ANSYS software, the temperature field and stress field of electron beam brazing (EBB) 1Cr18Ni9Ti stainless steel radiator by two kinds of process were numerically simulated. The calculated results of temperature field show, by the stage-by-stage heating process, the uniform temperature distribution of radiator faying face was obtained. The temperature of most regions is between 1042~1051°C, which is in the range of brazing temperature. The calculation results of stress field indicate, for radial residual stress, the obvious stress concentration region was found in faying face by direct-heating process; while there was no stress concentration in faying face by stage-by-stage heating process. For circumferential residual stress, compared the stage-by-stage heating process with direct-heating process, the peak value of tensile stress reduces by 11.2%. Compared circumferential residual stress with radial residual stress by two kinds of brazing process, the peak value of circumferential tensile stress is higher than radial tensile stress. So the dangerous position of faying face is along circle direction, namely, the heating direction of scanning electron beam. Consequently, the temperature difference between different positions in faying face must be controlled well during heating. The reduction of temperature difference can fall the peak value of tensile stress and improve the distribution of residual stress.


Sign in / Sign up

Export Citation Format

Share Document