Supporting tunnel face by Fiber glass pipes technology is an effective method to
maintain the stability of tunnel face, thus reducing surface settlements, face deformation
and maintaining the safety of the workers and the mechanisms used in tunneli
ng.
This paper presents the results of finite-difference numerical analyses (FLAC3D program)
on the behavior of a shallow tunnel face reinforced by longitudinal fiber glass pipes. A 3D
numerical model has been calibrated and used to demonstrate the effectiveness of this
technique, and perform a parametric study to determine the critical reinforcements
parameters (the density (number of pipes)(A) and length (L)). The results indicate that the
face reinforcement technique using longitudinal fiber glass pipes can significantly reduce
the movements (face displacement and surface settlements), and thus improving the face
stability. These movements decrease by increasing the length of the pipes and increasing
the density of the pipes until reaching the critical density, and when we reach the critical
length, the pipes must be renewed to maintain the stability of the tunneling process.
This paper presents and analyses the results of 2D and
3D numerical simulation conducted for the performance prediction
of TBM tunneling in clay soil.
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.
حددت الاستجابة السلوكية للفرمونات الجنسية في نفق الطيران لحشرة حفار ساق الذرة الأوروبـي
nubilalis Ostrinia و قد أخذت الذكور من مجتمعات متميزة، و من أنماط بيئية مختلفة (ذكور جمعت من
الطبيعة و أخرى ناتجة عن تربية كثيفة على وسط صناعي). أُجريت هذه الدر
اسـة فـي مخـابر المعهـد
الوطني للبحوث الزراعية-فرساي فرنسا عام 2004 .
و لتحديد هل لاختلاف نسب مكونات الفرمون الجنسي المختلفة تأثير في سلوكية ذكور حشرة حفـار
ساق الذرة الأوروبي اِستُخدمتْ كبسولات فرمونية صنعية تشمل سلالة E و سـلالة Z . أمـا الفرمونـات
الجنسية الطبيعية فكان مصدرها الإناث التابعة للسلالة Z.
