PSI - Issue 33

Muhammad Faiz Dzulfiqar et al. / Procedia Structural Integrity 33 (2021) 59–66 Dzulfiqar et al. / Structural Integrity Procedia 00 (2019) 000–000

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smaller load in the context is referred to as the allowable load. The ratio of the ultimate load to the allowable load is used to define the factor of safety, as quoted in Equation 3.

ultimate load allowable load

(3)

. F S



There are several considerations before selecting a good safety factor, such as materials, mode of the manufacturer, type of stress, general service, and shape of parts (Richard and Keith., 2015). Each of the aspects should be carefully considered and evaluated. If a chosen Factor of Safety is too small, the probability of the machine component becomes unacceptably large. On the contrary, if a desired factor of safety is unnecessarily large, the product is uneconomical and unfunctional design. The majority of safety aspects are specified by design specifications written by committees of experienced engineers working with industries or with country agencies (Beer., 2009). Example of such design specification codes are:  Steel: American Institute of Steel Construction, Specification for Structural Steel Buildings  Concrete: American Concrete Institute, Building Code Requirement for Structural Concrete  Timber: American Forest and Paper Association, National Design Specification for Wood Construction  Highway bridges: American Association of State Highway Officials, Standard Specifications for Highway Bridges 2.3. Deflection A deflection will occur while load and forces are being applied to the member of beams, and those phenomena form any movement of a beam from its original position (Xu et al., 2021). Several factors affect the deflection of a beam, such as the materials of a beam, the force applied, the moment inertia of the section, and the distance from support. The fundamental equation of beam deflection is denoted as Equation 4. 1 M EI   (4) Equation 4 is valid on any transverse section of a beam that is affected by transverse load. However, the curvature of the surface and the bending moment will differ from each section. Thus, it can be written as below (Equation 5) for the beam's distance section. 1 ( ) M x EI   (5) To determine the slope and deflection of the beam at ant chosen point, derive the second-order differential in Equation 6, which carries out the elastic curve.

2 ( ) d y M x dx EI 

(6)

Since EI is the flexural rigidity and its value can be differed along the beam, as in the case of a beam of varying depth, function of must be expressed before proceeding to integrate Equations 7 and 8. 1 0 ( ) x EI dy M x dx C dx    (7)