The purpose of this report is to determine the effectiveness of using shear walls with Moment-resisting frames by modeling two bare frame structures. The first model is a combination of bare frames and shear walls, and the second model is without she
ar walls, and analyzing them statically (LATERAL FORCE METHOD) and dynamically (RESPONSE SPECTRUM METHOD) using ETABS 2016 software, and comparing the results of base shear forces, displacements and vibration modes, in order to form a comprehensive understanding of the proper use of shear walls.
The report raises critical questions regarding the key factors of resisting seismic forces on similar structures, where rigidity or ductility can play opposing roles in the overall structure resistance.
The research aims to evaluate the micro shear bond strength of the calcium silicate cement
(Biodentine) and the glass ionomer cement (GIC) to dentine. The study was performed using
upper or lower premolars, and samples were divided into six equal s
ubgroups according to
the time period (3 h, 1 day, 1 week, 2 weeks, 4 weeks, 8 weeks), in order to study changes in
the values of shear bond strength with time. The comparative study showed that the success
rate of adhesion in the Biodentine group was smaller than that in the GIC group for the tested
premolars after 3 hours and one day, whereas the success rate in the Biodentine group was
greater than that in the GIC group for the tested premolars after 8 weeks.
Results showed a positive correlation between the mean values of shear bond strengths and
the studied time in Biodentine group, which ranged from 1.49 ± 0.18 MPa at 3 hours to a
maximum value of 2.65 ± 0.26 MPa after 8 weeks. While there was a negative correlation
between the mean values and the studied time in the GIC group and values ranged from 3.02
± 0.13 MPa at 3 hours and 2.06 ± 0.09 MPa at 8 weeks.
The study showed the advantage of Biodentine compared with GIC in terms of
micro-bonding to dentine, which can have a clinically significant importance in preventing
the micro leakage and reducing bacterial contamination.
The behavior of the basaltic shear diaphragms of the remaining buildings of ancient times
was investigated as experimental research,and its resistance to natural factors and
horizontal loads resulting from wind and earthquakes,to take advantage of
them in the
maintenance of modern buildings,which are associated with floors and beams as horizontal
shear diaphragmsIn the hot and cold areas of the African continent, Asia and other similar
areas,to replace the reinforced concrete shear diaphragms,and metal shear diaphragms that
lose their resistance to the above factors. When the buildings are inspected, the vertical and
slanted slits resulting from the side loads are placed,it was found that the appearance of the
cracks related to the hardness of the shear diaphragm section, the basalt stone
specifications and the design of the shear diaphragm base.The research was conducted
to determine the durability, water permeability and resistance to pressure and tensile
strength of basalt stone samples used in historic stone buildings and their location in
laboratory methods.Horizontal loads resulting from seismic intensity were determined on
the front of the building at the tile level according to international requirements and
specifications.The method of calculating the basaltic shear diaphragms was
applied by applying arithmetic to build a basalt stone from several floors and a basement,
taking into account the characteristic resistance of basalt, depending on its density from
pressure and stretching and basalt stone in calculating.
Structural Frame system is considers as an earthquake resisting structural
systems. On the other hand, many techniques were used to improve the
resistance against lateral loads. where Steel Plate Shear Wall fixed within
frame span is one of those
techniques.
This research aims to develop the Strip model of Partial Steel Plate Shear
Walls with Reinforced-Concrete Frame with opening parallel to beams.
This paper presents a study to reduction of heavy crude oil viscosity by
heating, where we select the best of temperature for all types instead of
constant temperature, whatever composition and viscosity of crude oil.
The goal of this study is to produce STFs and measure
their rheological behavior In order to select the appropriate STF for
liquid armor application.
Beams are considered as one of the most loaded concrete elements, which needs to
be strengthened either as a result of insufficient of concrete section, or insufficient rebar or
increased loads, or the result of a superficial steel or corrosion of
internal steel
reinforcement, and other reasons that we will mention them what we need to study this.
The damaged structural elements and their inability to function fully as a result of exposure
to different environmental factors damage materials and lead to lower resistance, or
because of the existence of of an executive defects or inappropriate investment for its,
leads to the need to rehabilitate maintenance and repair or reinforcement. So it was
resorting to strengthen either magnify sections or supply necessary reinforcement or steel
platelets linking external supported well to concrete section, and because of the difficulty
of execution the recent studies has been implemented on the use of more efficient material
which is concentrated fiber reinforced polymers.
We will present here to methods of strengthening the shear up to the global studies
conducted using these materials from polymers, which are characterized by high resistance
to tensile and large resistance to environmental factors and weather conditions and ease of
application in the specified permissible sites.
It was investigated in this study the influence of
Carboxymethylcellolose (CMC) solution concentration,
temperature, and pH on the rheological properties according to the
shear stress as function of shear rate. Experimental results show that
shea
r stress increase at all operational conditions as the shear rate
increase. When the shear rate is constant, the shear stress increases
also with the increasing of both concentration and pH as well as the
decreasing of temperature.
Using high strength concrete made a big step in designing and
constructing reinforced concrete structures. In this research, shear
resistance of high strength concrete beams with average resistance
of (65Mpa) and without shear reinforcement was ca
lculated by
making Experimental tests, also we studied the effect of cross
section shape on shear resistance, and measured the deflection in the
middle of the beams then we compared these results with the
mathematical results and with results from other researchers, finally
we developed a relationship to determine shear capacity in high
strength concrete T beams.
Many techniques have been used in repair and strengthening of
reinforced beam, among which are external steel beams, external
pre- stressing, epoxy injection, additional concrete overlay, external
steel plates, additional longitudinal and transver
se - steel bars.
Fifteen R.C. beams were tested until failure and the deflection,
surface strains, internal steel strains, external steel strains and crack
patterns were measured, the results were analyzed and conclusions
were summarized. Finally, the recommendations were stated with
the needed future work.