section modulus การใช้

• The plastic section modulus depends on the location of the plastic neutral axis ( PNA ).
• The section modulus of different profiles can also be found as numerical values for common profiles in tables listing properties of such.
• Often the equation is simplified to the moment divided by the section modulus ( S ), which is I / y.
• There are two types of section moduli, the elastic section modulus ( S ) and the plastic section modulus ( Z ).
• There are two types of section moduli, the elastic section modulus ( S ) and the plastic section modulus ( Z ).
• The plastic section modulus is used to calculate the plastic moment, M p, or full capacity of a cross-section.
• "' Section modulus "'is a geometric property for a given cross-section used in the design of beams or flexural members.
• The ideal beam is the one with the least cross-sectional area ( and hence requiring the least material ) needed to achieve a given section modulus.
• The farther a given amount of material is from the neutral axis, the larger is the section modulus and hence a larger bending moment can be resisted.
• When calculating bending stresses in a beam using Max Moment / section modulus, does it matter where that maximum moment occurs on the beam for this equation to work?
• Note that the ultimate strength of a beam in bending depends on the ultimate strength of its material and its section modulus, not its stiffness and second moment of area.
• Typically, and in this case, the struts are oriented such that the trunnion friction stress is applied to the weak axis of the struts ( see Section modulus ).
• The bending stress at any other point can be different than this, and is just the ( moment at that point ) / ( section modulus at that point ).
• Since the section modulus depends on the value of the moment of inertia, an efficient beam must have most of its material located as far from the neutral axis as possible.
• The stress ( which is what you're interested in ) varies with WxL / Z for a lateral load, where W is the weight, L the length, Z the section modulus.
• Though generally section modulus is calculated for the extreme tensile or compressive fibres in a bending beam, often compression is the most critical case due to onset of flexural torsional ( F / T ) buckling.
• The elastic section modulus is defined as Z = I / y, where I is the second moment of area ( or moment of inertia ) and y is the distance from the neutral axis to any given fibre.
• The plastic section modulus is the sum of the areas of the cross section on each side of the PNA ( which may or may not be equal ) multiplied by the distance from the local centroids of the two areas to the PNA:
• He correctly assumed a central neutral axis and linear stress distribution from tensile at the top face to equal and opposite compression at the bottom, thus deriving a correct elastic section modulus of the cross sectional area times the section depth divided by six.
• There may also be a number of different critical cases that require consideration, such as there being different values for orthogonal and principal axes and in the case of unequal angle sections in the principal axes there is a section modulus for each corner.