Stress concentration occurs due to the irregular stress distribution. Note that the stress concentration factor is a function of the geometry of a crack, and not of its size. A stress concentration factor is the ratio of the highest stress s max to a reference stress s of the gross crosssection. It is defined as the ratio of the highest stress in the element to the reference stress. Roarks formulas for stress and strain, 8th edition. Numerical analysis of stress concentration factors in order to verify the accuracy of the alfak soft ware, analysis of stress concentration factor was performed using numerical analysis in catia. Section 7 stress concentration stress concentrations produced by discontinuities in structures such as holes, notches, and fillets will be introduced in this section. Click download or read online button to get stress concentration at notches book now. A stress concentration factor is the ratio of the highest stress smax to a reference stress s of the gross crosssection. Corrosionpedia what is a stress concentration factor kt. Note that the stress concentration factor is a function.
A stress concentration also called a stress raiser or a stress riser is a location in an object where the stress is significantly greater than the surrounding region. Structures and materials section 7 stress concentration. This abrupt change can cause a higher stress or a lower stress by a certain factor in comparison to the nominal stress. Mechanical engineers reference book twelfth edition, 1994. Stress concentration factor defined in this fashion is called k n. Substantially revised and completely updated, this book presents stress concentration factors both graphically and with formulas. What causes a stress concentration is an abrupt change in the flow of stress through a part. A formula is developed to predict the peak stress concentration factor scf for analysis andor design in conjunction with the asme boiler and pressure vessel code, section viii, divisions 1 and 2. An object is more strong when it does not have any flaw, that is no sharp turns, no cracks and no holes. Stress concentration caused by sudden change in form.
The stress concentration factor for a circular hole in an infinite plate. The formula is rationally derived to include all of the parameters that are required to define the various penetration configurations used in. The stress concentration factor scf is as multiplier applied to the nominal stress to reach the peak or maximum stress at the hot spot location. T d a t d the maximum stress occurs on the inside of the hole, slightly below the shaft surface. The stress concentration factor for isotropic materials, such as metals and plastics, is determined using the procedure described in 18. Stress concentrations are deviations from the nominal stress on a part.
The factor which talks about how intense the magnitude of stress is concentrated in a certain region is the stress concentration. Petersons stress concentration factors, second edition. L convenient to think of kf as a stress concentration factor reduced from kt because of lessened sensitivity to notches. Pilkey, 9780470048245, available at book depository with free delivery worldwide. Petersons stress concentration factorspetersons stress.
Petersons stress concentration factors establishes and. The definitive work on stress concentration, revised and updated this second edition features the most comprehensive reference of stress concentration factors. Peterson, stressconcentration factors, wiley, new york, 1974, pp. Petersons stress concentration factors is a reference book for engineers and students concerned with increasing stresses at the intersection of changing. Pdf stress concentration factors download ebook for free. Stress concentration article about stress concentration. Three definitive sources for calculation methods of splines. The situation is somewhat different with anisotropic materials, such as fibrepolymer composites, because the stress concentration factor is dependent on the elastic modulus in different directions. Now the factor of stress concentration is a dimensionless factor used to evaluate the stress concentration in a material, there are many experimental method to calculate it. For static loading, you need to look at how is the material behaving in your operating conditions.
Finite element analysisbased approach for stress concentration. The stress concentration factor is defined as the ratio of highest stress in the body to the reference stress. Stress concentrations around notches were considered in chapter 3 with the stress concentration factor k t as an important parameter for characterizing the severity of the stress distribution around the notch. L if notch sensitivity data is not available, it is conservative to use kt in fatigue calculations. Structures and materials section 7 stress concentration 1.
Petersons stress concentration factors by zhuming bi, 9781119532514, available at book depository with free delivery worldwide. Charts of theoretical stressconcentration factors k. Reference stress is the total stress within an element under the same loading conditions without the stress concentrators. This book establishes and maintains a system of data classification for all the applications of stress and strain analysis, and expedites their synthesis into cad applications. Stress concentration free spline for high torque twin screw power transmission joe mattingly, steeramerica inc. T are not related to the properties of the material but rather depend on the type of stress concentrator, on its sharpness, absolute size, and size relative to the specimen. Petersons stress concentration factors edition 3 by. This irregular stress distribution occurs due to the different crosssections, the presence of sharp corners, sharp edges, notches or holes, keyways, scratches. The stress concentration factor calculators presented in this section calculate. Stress concentration factors 1974 edition open library. Approximate stressconcentration factors kts for a round bar or tube having a transverse round hole and loaded in torsion source. Petersons stress concentration factors, third edition researchgate.
Stress concentration factor is defined the ratio of the maximum stress. The book explains how to optimize shape to circumvent stress concentration problems and how to achieve a wellbalanced design of structures and machines that. The bible of stress concentration factorsupdated to reflect todays advances in stress analysis. Proceedings of fatigue, durability and fracture mechanics. Petersons stress concentration factors, 3rd edition pdf free. This new edition of the book has been substantially revised and completely updated and presents stress concentration factors both graphically and with formulas.
This book establishes and maintains a system of data classification for all the applications of stress and strain analysis, and expedites their synthesis into cad. Pdf numerical analysis of stress concentration factors. The notches are causing an inhomogeneous stress distribution, see figure 3. Index to the stress concentration factors xvii preface for the third edition xxxiii preface for the second edition xxxv 1 definitions and design relations 1 1. Petersons stress concentration factors by walter d.
Stress concentration at notches download ebook pdf, epub. For a notch sensitivity ratio of 1, the full stress concentration factor is used. Approximate stressconcentration factor kt for bending of a round bar or tube with a transverse round hole source. In petersons stress concentration factors, second edition by pilkey, a value of 2. Stress concentration caused by sudden change in form a change in the geometric shape of a part gives rise to additional stress over and above the calculated stress, which is known as stress concentration. The crack initiation period is followed by the fatigue crack growth period, recall figure 2. Stress concentration factor defined this way is denoted as k g. A stress concentration factor kt is a dimensionless factor that is used to quantify how concentrated the stress is in a material. Petersons stress concentration factors establishes and maintains a system of data classification for all of the applications of stress and strain analysis and expedites their synthesis into cad applications. Stress concentration 20022014 darrell socie, all rights reserved 1 of 63 outline 1. Figure 7 illustrates the stress concentration factor for path 1, and the mises stress concentration factor is approximately flat in the middle and increases or decreases close to the edges in the softer and harder components, respectively.
As the radius of curvature approaches zero, the maximum stress approaches infinity. Until now, the stress concentration factor for various isotropic structures is. Stress concentration factor an overview sciencedirect. What is stress concentration definition, causes, effects. The crack initiation life is highly dependent on the k tvalue. Petersons stress concentration factors book depository. The theoretical stress concentration factor, k t, 6 is defined as the ratio between the peak stress at the root of the notch and the nominal stress which would be present if a stress concentration did not. General basis 2 din 54662 splined joints calculation of load capacity part 2. Stress concentrations occur when there are irregularities in the geometry or material of a structural component that. A good analogy for stress concentrations is a river. Stress concentration factors charts and relations useful in making strength calculations for machine parts and structural elements by rudolph earl peterson. Stress concentration near a circular hole stresses at the edge of the hole at x a.
The applied loads were cycled in edgenotched 2024t3 aluminumalloy sheet specimens, which had a stressconcentration factor of 2, until local stress conditions stabilized. Petersons stress concentration factors, 3rd edition wiley. The present book contains some recently developed stress concentration factors, as well as most of the charts from the previous editions. Fatigue stress concentration factors lkf is normally used in fatigue calculations but is sometimes used with static stresses. The hot spot is the location in the tubular joint where the maximum applied tensile stress occurs. Determination of local stress histories was made by recording local strain histories during cycling and reproducing these histories in simple unnotched specimens. Stress and strain concentration factors of welded multiplanar tubular joints by romeijn, arie and a great selection of related books, art and collectibles available now at. This site is like a library, use search box in the widget to get ebook that you want. The value of the stress concentration factor is calculated by. Download citation petersons stress concentration factors, second edition this.
Petersons stress concentration factors wiley online books. The stress concentration factor will be capital k, lower case or subscript f, so kf, and thats your stress concentration factor for fatigue. A measure of stress concentration is the stress concentration factor. Stress concentration project gutenberg selfpublishing.
762 112 1210 1242 802 1345 1009 339 1486 284 1442 296 195 261 365 1433 918 1318 845 239 1414 1203 379 1364 1301 607 470 1398 534 221 405 1418 836