Institut za rudarstvo i metalurgiju Bor

GEO-MECHANICAL FEATURES OF
THE TERRAIN
The site prospecting up to 12.0 m
depth separates the layers of dikes, loamy
clays, dusty sandy clays and sandy clays
and clayey muddy dusts, Figure 2. The
last two layers can be divided into a dust
layer of clay sediments from lower layers
of silt materials. Below the layer above
the sandy gravel sediments , this prospecting
is not registered.
The results of site prospecting and laboratory
tests have given the information necessary
for further geomechanical calculations.
Data obtained in the laboratory are somewhat
better in relation to the terrain characteristics
defined during drilling and core from the
recording drillholes. This primarily refers to
the layer of clayey dusty sediments with interlayers
of muddy material.
In order to build these facilities, the
certain stability analysis for the coast natural
conditions and conditions that will occur
provided the construction of buildings was
implemented. For clayey dusty sediments,
the adopted parameters are somewhat lower
due to the presence of muddy components:
γ pot. = 9.6 kN/m 2 , φ = 10 0 and c = 8 kN/m 2 ,
where the following values were obtained:
• the natural state with no load, the water
level of 83.0 m, Fs = 1.226
• the natural state of the specified load,
water level 83.0 m, Fs = 1.112
Given the above analysis to date features
of the terrain, dust sediments are
favorable for the foundation support struc
tures which are planned to ensure the road
trunk. For improvement the security of
support structures, it is necessary to replace
materials with good quality gravel
from the river Sava, which in the good
conditions of compactness could be a stable
support. The replacement of material
will prevent the export of finest particles,
which would result into the terrain stabilization
of embankment.
CONCLUSION
The investigations, conducted for the
purpose of planning the right riverside of
the river Sava in Brcko, gave the necessary
information about the geological
structure and geomechanical characteristics
of the terrain. The laboratory testing
results are partly differ from the site data
obtained during the investigation and
mapping the drillholes. The differences
are related to the presence of sludge materials
in clayey dusty layer that deteriorates
its properties.
The analysis of stability for the riverside
natural conditions and conditions that
will occur in construction of buildings,
shows that the terrain is located somewhere
on the border between the natural
balance, so that each new intervention on
the ground require more detailed analysis
and calculations of terrain stability as well
as load of individual layers for foundations
of facilities.
No 1, 2010. 23
MINING ENGINEERING