This paper presents and analyses the results of 2D and
3D numerical simulation conducted for the performance prediction
of TBM tunneling in clay soil.
This Study presents results of experiments on smooth, thin square plates
with different central holes diameters to measure the drag coefficient of
flow through the plates.
The experiments were performed in a subsonic open wind tunnel at the
hydraulic laboratory, Faculty of Civil Engineering, University of
Damascus.
The surrounding conditions of tunnel lining may change
during the investment period which leads to a redistribution of
forces acting on the tunnel lining and perhaps gives new forces are not taken into account during the design. The behavior of the
tunnel should be analyzed for the new conditions and assess its performance through the stages of investment.
In this paper, a case study of Alsafkon tunnel which is one of
the Syrian Railway deep tunnels is regarded. The lining of this
tunnel suffers from cracks, leakage, and other defects.
To analyze the behavior of the tunnel lining, it has been
modeled using the finite element method software Phase for five cases that represent the investment conditions experienced by the tunnel from its construction to date. It was found that the lining cracks appear from the third phase which represents the case of immersion of the tunnel by the underground water. The formation of a weak lens adjacent to the tunnel detected by geo radar plays also an important role in the cracking of the lining of the tunnel.
The results of numerical analysis were in correspondence with the current situation of the tunnel in terms of distributed cracks places in the concrete lining. The study showed also the improvement importance of the lens properties to avoid the total fall down of the tunnel.
This research study the improvement of the performance of drying the agriculture products in (solar dryer-greenhouse), therefore; the design of the solar dryer had modified. The thermal storage unit became bigger, and the glass transparent roof cover
ed by thermal isolation sheet to reduce the thermal losses at night, a centurial fan was put on the drying tunnel to increase the speed of drying of Tobacco olives by increasing the hot drying air flue. The solar dryer tested in the tobacco researches center in Ramilah in Lattakia by drying samples of tobacco(Brly, Bassma) during the period of June,2013. The dried products in the solar dryer were completely protected from rains and insects, and the dried products are of high quality, The tobacco(Brly, Bassma) being dried in the dryer in four and three days, respectively.
To study the prevalence of the diabetic hand in a group of type 2 diabetics,
comparing to age- sex matched non-diabetics control group, and to investigate clinical features among
diabetics with or without the diabetic hand.
Tunnels are usually considered as important and costly constructions and
therefore it is very necessary to estimate their performance and analyze
their structural behavior to maintain their safety in order to ensure their
reliability and performan
ce during their hypothetical life.
In this issue we reviewed the situation of Syrian railway tunnels on Aleppo –
Lattakia axis from the field observations which show that these tunnel
linings are cracked.
The numerical method, which is known as Distinct Element Method, was
used in the analysis of cracked lining. This method performs modeling of
discontinuous systems. We focused in this study on the concrete type
through elasticity modulus and lining thickness. The result analysis shows
that the effects of cracks modify the distribution of stresses and
displacements in the lining. This modification is related to concrete elasticity
modulus and mechanical crack characteristics.
