scholarly journals Discussion: “The Determination of Safe Loads of Beams Subjected to Combined Twisting and Biaxial Bending Moments” (Hodge, Jr., P. G., and Sankaranarayanan, R., 1959, ASME J. Appl. Mech., 26, pp. 442–447)

1960 ◽  
Vol 27 (2) ◽  
pp. 364-364
Author(s):  
L. E. Malvern
Keyword(s):  
Bending Moments ◽  
Biaxial Bending

The Determination of Safe Loads of Beams Subjected to Combined Twisting and Biaxial Bending Moments

1959 ◽  
Vol 26 (3) ◽  
pp. 442-447
Author(s):  
P. G. Hodge ◽  
R. Sankaranarayanan
Keyword(s):  
Yield Criterion ◽  
Piecewise Linear ◽  
Yield Condition ◽  
Bending Moments ◽  
Collapse Load ◽  
Biaxial Bending ◽  
Suitable Parameter ◽  
Bound Theorem ◽  
Safe Load

Abstract Using the lower-bound theorem of limit analysis, a yield criterion is obtained in terms of the stress resultants for a beam, subjected to combined twisting and biaxial bending moments. Based on a piecewise linear approximate yield condition, the “collapse load” is determined for a right-angle bent, subjected to a load in an arbitrary direction applied to the mid-point of one leg. Such a collapse load, which is a “safe load” for the beam, is plotted as a function of a suitable parameter.

Determination of collapse moment of different angled pipe bends with initial geometric imperfection subjected to in-plane bending moments

2021 ◽  
pp. 095440622199640
Author(s):  
Manish Kumar ◽  
Pronab Roy ◽  
Kallol Khan
Keyword(s):  
Finite Element ◽  
Cross Section ◽  
Circular Cross Section ◽  
Initial Imperfection ◽  
Bend Angle ◽  
Bending Moments ◽  
Element Analysis ◽  
Geometric Imperfection ◽  
Initial Geometric Imperfection

From the recent literature, it is revealed that pipe bend geometry deviates from the circular cross-section due to pipe bending process for any bend angle, and this deviation in the cross-section is defined as the initial geometric imperfection. This paper focuses on the determination of collapse moment of different angled pipe bends incorporated with initial geometric imperfection subjected to in-plane closing and opening bending moments. The three-dimensional finite element analysis is accounted for geometric as well as material nonlinearities. Python scripting is implemented for modeling the pipe bends with initial geometry imperfection. The twice-elastic-slope method is adopted to determine the collapse moments. From the results, it is observed that initial imperfection has significant impact on the collapse moment of pipe bends. It can be concluded that the effect of initial imperfection decreases with the decrease in bend angle from 150∘ to 45∘. Based on the finite element results, a simple collapse moment equation is proposed to predict the collapse moment for more accurate cross-section of the different angled pipe bends.

Design Charts for Symmetrical Ring Girders

1957 ◽  
Vol 24 (1) ◽  
pp. 144-147
Author(s):  
G. P. Fisher
Keyword(s):  
Energy Analysis ◽  
Bending Moment ◽  
Bending Moments ◽  
Bending Energy ◽  
Normal Loading ◽  
Critical Design ◽  
Design Charts ◽  
Ring Location

Abstract Charts, based on classical bending-energy analysis, are presented for the determination of critical design moments in symmetrical ring girders varying in shape from circular through round to sharp-cornered rings. The girders are subjected to uniform normal loading in the plane of the ring. Location and magnitude of all critical bending moments are given, from which the maximum bending moment is easily selected.

Development of Secondary Stress Weighting Factor and Plastic Reduction Factor From Moment-Rotation Curves of Surface Cracked Pipe Tests

2017 ◽  
Author(s):  
S. Pothana ◽  
G. Wilkowski ◽  
S. Kalyanam ◽  
Y. Hioe ◽  
G. Hattery ◽  
...  
Keyword(s):  
Lower Bound ◽  
Stress Analysis ◽  
Elastic Stress ◽  
Weighting Factor ◽  
Reduction Factor ◽  
Bending Moments ◽  
Secondary Stress ◽  
Pipe System ◽  
Bend Tests

In flaw evaluation criteria, the secondary stresses (displacement controlled) may have different design limits than primary stresses (load-controlled stress components). The design limits are based on elastic stress analysis. Traditionally the elastic design stresses are used in the flaw evaluation procedures. But realistically a flaw in the piping system can cause non-linear behavior due to the plasticity at the crack plane as well as in the adjacent uncracked-piping material. A Secondary Stress Weighting Factor (SSWF) was established which is the ratio of elastic-plastic moment to the elastic moment calculated through an elastic stress analysis. As long as the remote uncracked pipe stresses are below yield, the SSWF is 1.0, and if the uncracked pipe plastic stresses are above the yield stress, the SSWF reaches a limit which is called the Plastic Reduction Factor (PRF). Four-point-bend tests were conducted on pipes with varying circumferential surface-crack lengths and depths. The moment-rotation plots obtained from various pipe tests were used in the determination of PRF. A lower-bound limiting PRF can be calculated from a tensile test, but pipe systems are not uniformly loaded like a tensile specimen. The actual PRF value for a cracked pipe was shown to have a lower bound, which occurs when the test section of interest is at a uniform stress (such as the center region in a four-point pipe bend tests). When multiple plastic hinges develop in a pipe system (a “balanced system” by ASME Section III NB-3650 design rules), this gives a greater reduction to the elastically calculated stresses since there is more plasticity. It was found that the plastic reduction is less when most parts of the pipe system remains elastic, or if the crack is located in the high strength/ lower toughness pipe or welds, or if the pipe size is large enough that elastic-plastic conditions occur even for a higher toughness material. Interestingly, it was shown that the same system with different loading directions could exhibit different actual PRF values if the change in the loading direction changes how much of the pipe system experiences plastic stresses. For smaller cracks, where the bending moments are high, the actual PRF is controlled by plasticity of the uncracked pipe, which is much larger than the plasticity that occurs locally at the crack. However, for large cracks where the bending moments are lower (closer to design conditions), the plasticity at the crack is equally important to the smaller amount of plasticity in the uncracked pipe for the actual PRF. Hence the plasticity of both the uncracked pipe and at the cracked sections is important to include in the determination of actual PRF values.

05.07: Structural behaviour of simple steel beams subject to axial compression, biaxial bending moments and torsion

ce/papers ◽  
2017 ◽  
Vol 1 (2-3) ◽  
pp. 1076-1085 ◽  
Author(s):  
Adrian Walter ◽  
Julia Herbersagen ◽  
Rebekka Winkler ◽  
Markus Knobloch
Keyword(s):  
Axial Compression ◽  
Steel Beams ◽  
Bending Moments ◽  
Biaxial Bending ◽  
Structural Behaviour

scholarly journals A COMPARISON OF TESTING METHODS FOR DETERMINATION OF SPRAYED CONCRETE TENSILE STRENGTH

2019 ◽  
Vol 23 ◽  
pp. 54-57
Author(s):  
Martin Závacký
Keyword(s):  
Tensile Strength ◽  
Tensile Test ◽  
Construction Material ◽  
Common Reason ◽  
Bending Moments ◽  
Testing Methods ◽  
Sprayed Concrete ◽  
Pure Tension ◽  
Splitting Tensile Test

Sprayed concrete is important construction material in tunnelling. Primary lining is essential in NATM where the sprayed concrete can be loaded by tension due to bending moments. The tension is common reason of failure because concrete has a relatively low tensile strength. The tensile strength is usually determined by splitting tensile test in laboratory. However, the results can be distorted because the specimen is not loaded by pure tension in this case. The paper compares results of concrete tensile strength determined by two methods: indirect by the splitting tensile test and direct by the modified tensile test.

scholarly journals Columnas Compuestas de Hormigón y Acero SRC, Sujetas a Flexocompresión Biaxial

2018 ◽  
Vol 3 (1) ◽  
pp. 281
Author(s):  
Jorge Ricardo Vintimilla Jaramillo ◽  
Luis Tinerfe Hernández Rodríguez
Keyword(s):  
Axial Compression ◽  
Bending Strength ◽  
Longitudinal Direction ◽  
Biaxial Bending ◽  
Load Curve ◽  
Composite Columns ◽  
Interaction Diagram ◽  
European Code ◽  
Made In

The work presented is based on experimental and theoretical analysis of SRC composite columns subjected to biaxial bending and axial compression, where the specification of American and European code criteria are used to calculate de load bending strength. The computer program to calculate the interaction diagram of biaxial bending and axial compression with inclined neutral axis is made in the software Matlab by using the fiber method, besides, the strength of the specimen is calculated. Users can design new frame sections and check the exist sections. To obtain the displacements and load curve, to calculate load contours and determination of the interaction family curves of the modeled sections. The destructive performance of the round and rectangle composite columns are made in the structures laboratory of EPN to obtain the results such as the buckling displacement at strong, weak and longitudinal direction measured with LVDT´S. Subsequently, the theoretical and experimental analysis results are made to demonstrate the reliability of the numeric model.Keywords: Composite Columns, Concrete, Steel

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