In this paper, the modeling methods of tunneling and the surface subsidence induced by
that have been studied by using two-dimensional numerical analysis according to the FEM
method, assuming the green field condition، which means that there is no
load on the soil
surface above the tunnel. A FE study was conducted in which an elasto-plastic constitutive
model was adopted to model the soil behavior (HS, HSsmall).
This article includes a comparison between the results of numerical analysis and field
measurements to executed projects، and a suggested method for modeling tunnel
excavation and surface subsidence induced by that.
This paper concerns the mathematical, linear model of micropolar
elastic, homogeneous and isotropic body, of axisymetric state of
small deformations, in the frame of the linear theory of micropolar
elasticity with six material constants . In the p
aper, first
we introduce the dynamic displacements-rotation-temperature
equations for the considerable body in the axisymetric state of
small deformation , subjected to temperature field.
الجسم المرن البلوري ذو انفعالات صغيرة متناظرة محوريا و خاضع لحرارة
تركيب معادلات الإزاحات و الدورانات و الحرارة
الحلول الشاذة
Micropolar elastic body of axisymetric state of small deformations and subjected to temperature field
decomposing the dynamical displacements-rotationstemperature equations
singular solutions
This research aims to study the deformations creep in clayey soils
treatment with calcium chloride.
Creep experiments were carried out on samples of soil was added
with different ratios of calcium chloride compound, was measured
deformations with time and monitor the impact of the proportion of
calcium chloride added to the soil to these deformations.
In this paper, ground surface settlement induced by tunneling have been studied
using 2D finite element analysis. By assuming greenfield conditions, which means that
there is no loads on the soil surface above the tunnel.
A FE study was conducted
in which an elasto-plastic constitutive model was adopted
to model the soil behavior (MC,HS).
This paper include Comparison between actual field measurements with (FEM)
results, and parametric study for the most factors that influence ground surface settlement.
There are many sources that cause the emergence of geometric deformations in close
range images. These deformations are accumulated and not present singly in the image.
Therefore, it is necessary to rectify (correct) the image before extracting geo
metric or
semantic data from it.
Two methods are available to rectify the close range images. These ones are the
parametric and the non-parametric methods. Non-parametric approach does not require
knowledge of the parameters of the used camera. Control points and geometric
transformations are considered as the two main components in the non-parametric
approach.
Usually, barrel and perspective deformations are present in close range images. In
this paper, we will study the impact of the distribution of control points and the degree of
geometric transformation on the correction of the image of these deformations. The test
was performed using a close range image of a historical façade. This image was exposed to
previous deformations by simulation. The goal is to investigate the effect of the
distribution of control points and on the effectiveness of global (linear) and local
transformations used to rectify the close range images. It has been demonstrated that the
control points located in different parts of the image have different deformation rates, the
control points distributed in the center of the image suffers less deformations, and local
transformations give the best results when rectifying images with complex deformations.
The copper wire drawing is one of cold forming operations which
basicly the copper is used as pure material for various diameters &
sections in electrical conductors industry.
By cooperation with S.M.C company for cables industry in
Damascus – Sy
ria, a research has been done during 2 years on rod
breakdown heavy drawing machine -HENRICH - GERMANY- 2
lines- with max productivity 25 ton/24hr.
50 samples of copper wire breaks and deformations have been
studied & analyzed, thus the defects are classified in main statistics
diagrams in gold of give main instructions that contribute in raising
the quality level of local copper wire manufacturing & giving a
whole view about this industry.
The mixed use of steel bars and carbon rods in concrete beams can offer beams with different behaviour from that of steel reinforcement only. This paper studies the case of reinforcing concrete beams with two layers of bars, and the main parameters
investigated are the proportion and the distribution of carbon rods in the cross-section. Four groups containing 12 beams are tested, and each is reinforced with 4 bars located in two layers. The first group includes three control beams reinforced with steel bars, while the second includes three beams reinforced with carbon bars. Each of the third and fourth groups includes three beams reinforced with two steel bars and two carbon bars, whereas in the third group, steel bars are located above carbon ones, but in the fourth group, steel bars are located under carbon ones. Concrete beams reinforced with carbon rods in the second group exhibit a higher load carrying capacity and deflections, compared with other beams. However, the beams in the third and fourth groups have approximately the same load carrying capacity and the same behaviour up to the load level equal to 75% of their load carrying capacity. But after that, the beams in the fourth group become more deformed, compared with those of the third group.