The problem of slope stability is considered as a main geotechnical problem due to the
significant damage (material or moral) related to failure. This paper aims to study the
influence of piles on the stability of slopes loaded with strip footing a
nd investigating the
parameters affected on stability (location of pile row relative to the slope crest X , piles
spacing S , piles length L and edge distance of the footing b ). This study has been realized
in two phases : the first phase consists in establishing a numerical model for sand slope by
using finite element analyses program (FLAC3D) and determining the footing settlement at
crest of slope before using piles and after reinforcing , after that the numerical results is
compared with the experimental ones (reference case ). A close agreement between
experimental and numerical curves is noticed .The second phase deals with studying the
influence of most important parameters such as ( piles length ,piles spacing, pile row
location relative to the slope crest on stability and edge distance of the footing) on the
slope stability. The results of parametric study have shown the piles installed near the slope
crest is more efficient in reinforcing where the safety factor is increased by reducing the
distance between row of piles and slope crest and the greatest value for safety factor when
X=0.7Lx . The currently study showed the efficiency of piles to increase the ultimate
bearing capacity with increasing edge, after that at b=3B the increase in ultimate bearing
capacity decreased. Also the slope stability depends significantly on pile length and it
increases even reaching the length equals the height of the slope. At other hand, the safety
factor is reduced by increasing the piles spacing, so that the efficiency of pile is
disappeared when pile spacing equals to six times pile diameter(UBCR<1.1).
The aim of this study was to study the plant species diversity at Al-Kahaf protected
area in A-Sheikh Badr region, Tartous governorate, in terms of functional
characteristics of the recorded plant species, its uses. The results can contribute
in u
nderstanding, and determining the role of those plant species for ecosystem
function and local community and help in the management of this protected area.
Plant species diversity was studied on three versants; using the intercepted line
method; and in the watercourses surrounding Al Kahaf castle. Additional surveys
have also been conducted over the whole site. Life forms, dispersal types, and the
uses of these species were recorded. The recorded species belong to 53 plant family.
Fabaceae was the most represented family (17 species), followed by Asteraceae
(12 species), and Lamiaceae (11 species).
The main aim of this study was to determine the effect of slope position on some
soil physico-chemical properties .The study was conducted on a pine forest soil , Tartous.
Soil samples were collected from top , mid and bottom slope positions at hor
izon- A and C
of top and mid slope positions and at horizon A,(B)and C of bottom slope positions .
Results showed a significant difference among the physico-chemical properties of top ,
mid and bottom slope soils . Bulk density of the top - slope (1.34 gcm-3) was the highest
followed by mid ( 1.31 gcm-3) and bottom slopes (1.27 g cm-3) .Conversely ,Organic
matter content (2.86%) ,electrical conductivity EC(0.20mmos/cm) , calcium(28.3
meq/100g) , magnesium(6.80 meq/100g) , Potassium (0.21 meq/100g), Soil pH ( 7.95) ,
clay content (38.43 %) and silt content (34.70%) were the highest at bottom slope followed
by mid and top- slopes , respectively . Soil A and C horizon of top and mid slope positions
and A ,(B)and C horizons of bottom slope positions were also significantly different in
their physical and chemical properties . Horizon A had the highest organic matter
,electrical conductivity , calcium , magnesium , silt contents and lower bulk
density,CaCO3, sand contents than both the (B) and C horizons of bottom slope and the C
horizon of top and mid slope .The deterioration in physico-chemical properties of top slope
as compared to mid and bottom slopes and that of A horizon as compared to C horizons
were presumed to be due to past soil erosion effect that removed the finer soil particles
including soil organic matter and other plant nutrient.
This research aimed to study the natural regeneration of Pinus brutia in Qurdaha
region, and to determine the most important factors affecting the regeneration. 42 circular
samples were taken, the area of each sample was 400m2. The following measur
ements were
taken: geographic coordinates of each sample's centre, altitude, aspect, the slope, forest
litter thickness, the proportion of gravels, stones and rocks, tree, bushes and herb cover.
Forest inventories were achieved using Braun-Blanquet method. Which, the number of
sample seedlings, the seedling height, seedling diameter, the seedling age, burning trees
and alive trees of Pinus brutia were registered. The results showed a significant negative
effect of slope and a significant positive effect of herb cover, where the percentage of data
classification by the model was reached 74.4%, while the Nagelkerke R2value was 37%.
The negative effect of the slope comes from increasing the risks of soil erosion and the loss
in their nutritional elements. In contrast, the positive effect of herbal coverage is the
contribution to reducing the risks of summer drought that can be affect the seedlings.
This research aims at finding the model of rainfall carnal slope
in Kastal Mouaf-Coastal basin . Statistical analysis has been
performed during 48 year ( 1961-2009) using spss v.22 to
represent the relationship between the rainfall and the factors
whose impacts are shown by the passage time .
The pelvis anatomy and position, interact with the lumbar spinal organization in shape and position to regulate the sagittal balance between both the lumbar spine and pelvis. Sagittal lumbar-pelvic balance of the human body may be analyze by a pelvic
parameters ( pelvic incidence (PI), and sacral slope (SS)) and shape of the spine (lumbar lordosis (LL) and spinal morphologic type). Hamstring muscle tightness (HMT) causes rotating backward the pelvis (retroversion) which decrease lumbar lordosis. We measure PI, SS, lumbar lordosis and spine type on lateral radiographs of 21 patients with lumbar disc herniation (LDH) and 50 spinal healthy subjects and evaluate HMT by straight-leg-raising test (SLR-test). The lumbar-pelvis parameters for patients with DH demonstrated to have a mean PI, SS and LL equal to 48.85°, 37.9°and 47.28°, respectively, versus 52.24°, 42.88° and 59.24°, respectively, for the control group. Patients with a LDH were characterized to have PI, SS and LL significantly lower than the control group. Also DH group has a mean SLR-test equal to 74.85°, significantly lower than control group (82.24°). We notice also that spine type I and type II are more frequently in DH group. All results give that DH group has vertical spine more than control one, which mean that the DH patients have vertical pressure on lumbar discs more than normal subjects.
The pelvis anatomy and position, interact with the lumbar spinal organization in shape and position to regulate the sagittal balance between both the lumbar spine and pelvis. Sagittal lumbar-pelvic balance of the human body may be analyze by a pelvic
parameters ( pelvic incidence (PI), and sacral slope (SS)) and shape of the spine (lumbar lordosis (LL) and spinal morphologic type). Hamstring muscle tightness (HMT) causes rotating backward the pelvis (retroversion) which decrease lumbar lordosis. We measure PI, SS, lumbar lordosis and spine type on lateral radiographs of 21 patients with lumbar disc herniation (LDH) and 50 spinal healthy subjects and evaluate HMT by straight-leg-raising test (SLR-test). The lumbar-pelvis parameters for patients with DH demonstrated to have a mean PI, SS and LL equal to 48.85°, 37.9°and 47.28°, respectively, versus 52.24°, 42.88° and 59.24°, respectively, for the control group. Patients with a LDH were characterized to have PI, SS and LL significantly lower than the control group. Also DH group has a mean SLR-test equal to 74.85°, significantly lower than control group (82.24°). We notice also that spine type I and type II are more frequently in DH group. All results give that DH group has vertical spine more than control one, which mean that the DH patients have vertical pressure on lumbar discs more than normal subjects.
Cracks of irrigation channel’s service roads are becoming a significant feature in Al-Ghab region. All information indicates that lateral spreading of stresses in slope vicinity induced cracks in the side parts of roads. These cracks resulted from la
teral displacements, which could dominate total displacements. This
paper presents a geotechnical evaluation of the possibility to mitigate this phenomena by using geogrid soil reinforcement. Finite elements numerical model analysis is performed to calculate total, horizontal and vertical displacements at road side near channel’s slope. Numerical models include different cases of
un-reinforced soil and geogrid reinforced soils at different locations. Locations of geogrid were chosen carefully to attain the best effectiveness. Beneficial factor and coefficient of efficiency were determined for reinforced road.
Rock slope failures usually occur along the structural
discontinuities in rock masses, but for weathered and highly
jointed rock masses, failure surfaces are often curved as in soil
slopes.
This paper is concerned with stability analysis of weath
ered and
highly jointed rock slope using shear strength reduction technique by FLAC program, which uses finite difference method.
This paper presents a stability analysis of a rock slope in Khneifees
mines in Syrian desert, to verify that it is safe for workers and
equipments to work beside it, and manipulates the result charts
of FLAC analysis using finite difference method and shear strength
reduction technique to assess the stability of the rock slope,
determine the safety factor of the rock slope and expect failure
mechanism.
This research was carried out in five sites varied in altitude representing Mediterranean vegetation zones of western slopes of Lattakia Mountains during 2010 - 2011 on Quercus infectoria Oliv species. Research shows that significant difference of al
titude above sea level has obvious effect on seed germination in different sites. This is noticed in characteristics related to fruit weight, germination rate value sum, and height of vegetal and rooty seedling after four months of germination. Altitude above sea level has no effect on the branchlet number of rooty and vegetal sum height of seedlings as well as mean of leaves number of seedlings. According to germination ratio and daily germination ratio, in addition to seedling diameter, there is harmony among all sites. It can be deduced that there are changes in growth traits of studied seedlings in different sites. This is the primary indication of the impact of the altitude above sea level on seedling traits of Quercus infectoria Oliv.
