Bending
of
a
Channel
Section
Experiment Two: Stiffness Report from laboratory work performed on 12 May 2011 as a part of the unit of study CIVL2201 Structural Mechanics
Abstract
This report has been written to describe an experiment performed on a channel section examining the stiffness of the beam through two differing types of deformation – curvature and deflection. The aim of the experiment was to determine the value of the flexural rigidity (EI) in two different ways; using the curvature, k, and the mid-span deflection. The testing method used for the experiment is described. The experiment found that the EI values calculated were as follows: - EIcurv = 1.76E+10 Mpa.mm4 when calculated using the curvature, k. - EIdefl
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Table
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Plotting
P
against
the
Midspan
deflection
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Figure
5.
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Table
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Discussion
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Conclusion
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References
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22/05/2001
2
Bending of a Channel Section
Introduction
This report aims to describe the experiment performed to investigate the stiffness of a channel section, and in particular calculate the flexural rigidity (EI) of the beam by two different sets of calculations based on the results gained in the experiment. The EI of an object is used
The goal of the beam project is to design and construct a beam that can hold a given amount of weight without breaking. The beam is required to hold a concentrated load of 375 lbf on the X-axis and 150 lbf on the Y-axis. The maximum allowable weight of the beam is 250 grams. The maximum allowable deflection for the beam is 0.230 in. and 0.200 in. for the X and Y-axis respectively. The beam is required to be 24 in. in length, and it will be tested on a simply supported configuration spanning 21 in. All calculations are to be done under the assumption that the density of basswood is 28 lbm/ft3 and the modulus of elasticity for basswood is 1.46x106 lbm/in2. Given the constraints of a spending cost of $10.50, a maximum beam weight of 250 grams,
Overall, my team used this structure because it is used for strength and weight distribution, so my team decided to use triangular shapes as the beams in order to take the force acting at one point of the bridge and wide it. This will
The comparison of measurement and prediction of prestress losses in prestressed members is highly documented in literature. Hale et al. (2006) studied the prestress losses behavior of girders subjected to increased fiber stresses. They concluded that the previous AASHTO LRFD Specifications equations (2004) overestimated the prestress losses by roughly 50%. It was found that the NCHRP Report 496 (Tadros et al., 2003) equations predicted the losses to within an average of 6%. Currently, there have been quite a few investigations on empirical models for prestress losses for HSC. In a study conducted by Kowalsky et al. (2001) on several HPC bridge girders in North Carolina to determine the prestress losses of HPC girders. The researchers found shrinkage losses were a small component of the overall prestress losses and that the elastic shortening and creep losses were the main contributors. These larger than expected losses from elastic shortening and creep were because of a predicted modulus of elasticity that was higher than actual. The total prestress losses ranged from 12.9% to 19.1% of the initial jacking stress. In an investigation conducted by Tadros et al. (2003), seven full-scale bridge girders were instrumented in Washington, Texas, Nebraska and New Hampshire to determine the prestress losses of HPC girders. The total prestress losses measured were found to be lower than the AASHTO LRFD (1998) model. Modified expressions were proposed to AASHTO and later adopted in
One thing that has been brought up as a concern for the hospital is using unistrut versus structural steel to hold booms from the ceiling. Unistrut tends to move too much and causes too much movement in the booms when doctors are in surgery. The engineer on the project has started to investigate this problem and has agreed to use structural steel instead of unistrut. In my Structural Systems I class, we learned how structural steel deflects with certain
Purpose: The purpose of this Physics Lab is to investigate what factors determine the amount of flexion of the cantilever. Hence, the objective is to establish a relationship between the length of a cantilever, which may give some insight into the physics of cantilevers.
If the load is applied at the mid- length a=b=L/2 then mid span deflection is:
Structural researchers have realized the beam-column joint’s effects and consequences on the stability and durability of structures since the last century. Many buildings were collapsed under exposure to earthquakes; in most cases the main reason for its collapse is the local failure in beam-column joints. Therefore, many attempts have been done by structural researchers all over the world to overcome these crises by improving the resistance capacity of joints. The amount of steel reinforcement both longitudinal or transverse direction, and distribution pattern of it have a significant effect on the behavior of joints.
Several mechanical tests have to be applied for measuring static and dynamic properties of materials and most of them involve applying a force to the material and measuring its displacement. Through these tests, measuring the stress applied and the resulting strain, it is possible to calculate material properties such as the Young modulus, the physical parameter corresponding to the material stiffness.
The experiment was done to investigate the shear force and bending moment in a beam. A shear force in a beam experimental frame and a bending moment of a beam experimental frame was used along with the digital force display unit to conduct the experiment. When the force increases with constant distance from the cut, the shear force and bending moment would increase. In the second experiment, the load is placed at a specific distance to the left of support A. The shear force and bending moment is than obtained and calculated using the formula that had been given in the handout.
The studies begin with the development of the initial concept, the continuous floating constraint buckling column. This concept consists of a flexible composite column, under axial loading, buckling to higher modes between rigid lateral constraints. The concept is proven by a comprehensive experimental demonstration. A dynamic FEA model of that system is developed and studied. Experimental response proved consistent with FEA results. The model accurately predicts buckling forces, lateral reaction forces, stresses, strains, friction, modal shapes, and deflection. The geometric variables of the continuous floating constraint were optimized using the FEA model, and final tests were carried out.
A beam with a constant height and width is said to be prismatic. When a beam’s width or
Measurement of shear modulus is also necessary. Two methods are reviewed for obtaining shear modulus: the Iosipescu shear test [15] and V-notch rail shear test [16]. Both of these tests have a rectangular specimen with notches cut in order to concentrate shear stress at the neck. It is how the specimen is loaded differentiates these two tests. The Iosipescu method utilizes a special equipment which loads the specimen along its edges by exerting compressive force. The V-Notched rail shear method uses another specialized fixture to grip the faces of the specimens and shears the specimen in tension. These two methods apply different forces in different locations of the composite specimen, therefore, it is reasonable to expect that each of the two approaches can give slightly different shear modulus. Yan-lei et al. evaluated these two methods in his study [17]. Although the Iosipescu shear specimens can give good results, he claims that edge crushing can be an issue due to the way the specimen is loaded into the fixture. And V-notched rail shear method can get rid of such unacceptable failure and it uses a larger gauge section, so this method has more
The aim of the project is to find the steady-state temperature distribution in a beam. Since it’s impossible to solve the model analytically due to the irregular geometry of the cross-section, the temperature distribution will be found using ANSYS-Mechanical to model the problem and solve using the finite element method.
Thin walled structures are an important part of engineering construction with territories of use becoming diverse continuously ranging from girder bridges, oil vessels to industrial warehouses , framed structures. Thin walled sections have various stresses and failure modes which can be difficult to predict. Thus structural engineers need help of computers for analysis of these structures. This has been done by using software called THIN-WALL which estimates the cross-sectional properties of the section according to the Vlasov theory. The method of input data for thin walled structure has been explained in this paper. Also the buckling analysis of the thin walled sections has been done using CUFSM which is based on the finite strip method. This method has been explained in the paper and the results the analysis have been compared with the hand calculations according to the Canadian code s-16. The results have been discussed and on basis of this review conclusions have been presented.
I have maintained a 15-year research connection with partners in the Department of Defense (DOD), interacting with five DOD program managers (PM). They include the PM of ONR’s solid mechanics program (15-year interaction), PM of ONR’s ship structure program (12-year interaction), PM of ONR’s polymer composite program, PM of Air Force Office of Scientific Research’s (AFOSR) structural mechanics program (five-year interaction), and PM of Army Research Office’s (ARO) mechanical behaviors of materials program. I interact with numerous researchers at the