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.
Experiments Has been made on lime mortar which have a weak
resistance so we added materials like pozolan, and bricks to
improve the mechanical properties of the mixture, as we added
fiberglass to the mix, and study their effect on the mechanical
properties of mortar, also experiments has been made on natural
limestone which used in the construction, experiments on samples
of mural prismatic composed of stone and mortar to see pressure
strength of mural samples, and mural samples subjected to
curvature to determine tensile strength of stone walls with
limestone mortar reinforced with fiber glass.
We observed increase in the mural samples tensile strength about
73% when we added a small amount of fiber glass doesn't exceed
2% of the proportion of the existing lime in the mixture, which
shows the effective improvement in the mortar extracted
specifications.
Restoration of ancient structures is an important part of
reconstruction process which will be witnessed by our country, the
aim of this research is to improve a local manufacturers lime mortar.
This research aims to study the effect of addition the filling materials (sodium aluminosilicate, Talc) to the unsaturated polyester(unsaturated polyester resign)(UPR) first, and unsaturated polyester reinforced by fiberglass (20%) secondly, Number o
f mechanical tests were done, they included (Tensile, Flexural Strength). The effect of addition of filling materials sodium aluminosilicate (SAS), Talc, and a mixture of sodium aluminosilicate and Talc to the unreinforced polyester with fiberglass was studied in the first step of the research, and the results showed that the best values were gotten when adding a mixture of ((SAS) and Talc) at ratio (10% SAS,5% Talc), where the tensile strength value raised up from (31.2 MPa) to (33 MPa), and the elastic module value also raised up from (2330 MPa) to (2750.5 MPa) , and the flexural strength value also raised up from (0.057 GPa) to (0.0729 GPa). The effect of addition of filling materials (sodium aluminosilicate, Talc, and a mixture of sodium aluminosilicate and Talc ) to the reinforced polyester with fiberglass (20%) was studied in the second step of the research, and the results showed that the best values were gotten when adding a mixture of ((SAS) and Talc) at ratio (5% SAS,5% Talc), where the tensile strength value raised up from (101.7 MPa) to (108.8 MPa), and the elastic module value also raised up from (5616 MPa) to (6367.9 MPa), and the flexural strength value raised up from (0.1203 GPa) to (0.1597 GPa).
This research includes an experimental study for the manufacture of
a composite material based on polymer (unsaturated polyester),
reinforced with random fiberglass at different weight fractions. By
suite, it has been studied some mechanical prope
rties of the models
manufactured, to determine the effect of glass fiber content on the
tensile strength, hardness and impact resistance. This study has
shown that the best results were for samples reinforced by 40%
fiberglass, where the tensile strength increased about 70%, hardness
up to 30%, and impact resistance about 43%. It will be observed
that the mechanical properties decrease clearly at 60% of weight
fraction of fiberglass. This fact can be related to the quantity of
unsaturated polyester become inadequate for recharge of the fibers,
which leads to weakness in the forces bonding in composite
materials.
