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Stress is a physical quantity that averages over internal forces (e.g. van der Waals forces, Ionic bonding, collisions, ...) that neighbouring atoms/molecules of a material exert on each other. If a force acts on an object, it causes stress inside the material. Stress behaves like a fluid in the sense that stress flows trough the material. Now, if there is a ...


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Epoxy is designed to be stronger than concrete. So ultimately we will have two failure modes: 1 - If the embedment of the screw in the concrete is not enough to develop the yield limit of the screw the failure will be that a cone of concrete opening up to the surface of the concrete will punch out explosively. The surface area of this cone multiplied by the ...


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The answer is no. A little oscillator might generate a watt or two, but large buildings are not only well-damped but also mass-controlled with respect to their responses to being vibrated. Most of the power generated by the little oscillator will be reflected off the building's structure and whatever makes it in will be quickly dissipated.


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If it was me I would use I beam for the entire frame and gooseneck I built one that I pulled with my 2500 HD silverado and used 4 x4 x 30# I beam it was 25ft with a 3.5 ft dovetail and I hauled my pulling truck on it... And my other one is a gooseneck as well but it is made with 12 x 14 # high-tensile steel and I have with the dovetail included a total of ...


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Welding a beam to a column can deform the column at its bending axis. The axial load on a steel column is determined by multiplying the moment by a bending factor. The bending factor is the area of the cross section divided by the section modulus. These factors are tabulated in the AISC Manual for the x and y axis. When a portion of that cross section is ...


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You are right. It is easier to do a weld under the specified heat and approved specs in a shop likely by a robot and get the welds pre approved by the authority in charge as a large batch. As opposed to having to pay a license welder and a authorized weld inspector. Bolts could be torqued by automatic torque wrench easily on the job site. This saves time, ...


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Manufacturing methods for structural steel shapes result in stresses that remain in the material after the section has been formed. Those residual stresses have an impact on the buckling curve and are a major reason the design curves are distinct from the theoretical Euler buckling curve. In hot-rolled sections and welded sections, the residual stresses are ...


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The only material factor is the material strength, The themo-mechanical processing to get to the strength makes no difference. All oil well casing designs have a buckle calculation,they are round but I expect the same principles apply. For thinner sections such as in the shown figures , the yield strength was used . For thick sections the tensile strength ...


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The cold-formed pieces will exhibit less elongation before yielding because cold work has been performed on them. The hot-formed pieces will exhibit more elongation before yield because they have been annealed into their unworked state.


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The moment diagram for the shear diagram you have assumed is correct assuming the graph of the moment at any point is the area of the shear diagram up to that point. These typical average shear diagrams are used by codes such as AISC specifications J3.-, provided one uses the criteria therein. However, if you really want to investigate the hypothetical ...


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Second moment of inertia is a property of a surface measuring its area distribution from its neutral axis. In engineering it is closely related to bending moment resistant. Let's see why: In materials with linear stress/strain ratio, with a constant modules of elasticity like steel, wood, plastic, metals, the deformation of section along depth of the beam is ...


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The Second Moment of Area stems from the Radius of Gyration. Radius of gyration is the root mean square distance of particles from the axis. In other words, it's an average distance to the particles of a rigid body from an axis, that is squared to eliminate the negative signs. Looking at an Area, A, that is rotated about X-axis, the radius of gyration is ...


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For a large structure, the wind load will not reach its peak value on all surfaces at the exact same time, but at slightly different points in time. Therefore, the ability of the maximum total wind load to excite dynamic vibrations in the structure may be reduced compared to the simplification of multiplying peak pressure with total area and applying that as ...


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Many of the solution techniques are only now used because we have computers. Trial and error was used - many buildings failed both during and after construction. Look at how churches had to have buttresses to keep the walls in place as they got bigger - did they have the maths to calculate those? Or even the theory? They did come up with empirical formulae - ...


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The frequency and ground acceleration and other pertinent data are recorded in a seismic design espectra which is unique for each site and varies with the type of the soil on the side. Usually building department will have that information. For example the following is the link to Los Angeles building department site for design espectra. https://data2.scec....


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