Experimental and theoretical fracture assessment of rock-type U-notched specimens under mixed mode I/II loading

Sangsefidi, Milad; Akbardoost, J.; Mesbah, Majid

doi:10.1016/j.engfracmech.2020.106990

Cited by 37 publications

(14 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…and higher values of biaxiality ratio reveals that the T-stress has considerable magnitude compared with the stress intensity factor (K) and neglecting the effects of such noticeable non-singular term may reduce the accuracy of predictions in singular (K-based) fracture criterial as demonstrated in previous works. [78][79][80][81][82][83][88][89][90][91][92][93][94][95][96][97][98][99] In order to use the GMTS and GMTSN criteria for predicting the onset of mode II fracture, the corresponding value of fracture process or damage zone size (r c ) and the value of T-stress are required parameters. While r c is a material parameter and constant for any material (i.e., HMA mixture of this research), the T-stress is geometry and loading type dependent parameter, and its value may differ from one specimen to another test sample.…”

Section: Resultsmentioning

confidence: 99%

Influence of testing method on mode II fracture toughness (K_IIc) of hot mix asphalt mixtures

Liu

et al. 2022

Fatigue Fract Eng Mat Struct

View full text Add to dashboard Cite

Till now, only very limited test results have been reported for mode II fracture toughness (KIIc) of asphalt mixtures. In the absence of any standard testing method for determining KIIc value for these materials, in this research, an experimental program is done to measure and investigate this parameter at low‐temperature using four different test specimens and configurations. The specimens have circular and semi‐circular shapes but with different crack types and loading setup namely: center cracked circular disc (CCCD), inclined cracked semi‐circular bend (ISCB), asymmetric semi‐circular bend (ASCB), and asymmetric edge notch disc bend (AENDB). The test results showed that KIIc depends significantly on the geometry and configuration of test sample such that its value determined from the AENDB sample is about twice the KIIc value of ISCB specimen. Among the investigated samples, the AENDB results can simulate more realistically the actual and field conditions of real cracked overlays subjected to traffic loading. KIIc results are also predicted successfully using two fracture criteria capable of considering the influence of geometry on mode II cracking.

show abstract

Section: Resultsmentioning

confidence: 99%

Influence of testing method on mode II fracture toughness (K_IIc) of hot mix asphalt mixtures

Liu

et al. 2022

Fatigue Fract Eng Mat Struct

View full text Add to dashboard Cite

show abstract

“…Some researchers studied SIFs in an orthotropic medium using the singular integral equation and the R-curve method [ 37 , 38 ]. U-notches subjected to mixed-mode I/II loading were analyzed in fracture conditions in references [ 39 , 40 ]. In references [ 41 , 42 , 43 ] the analyses were focused on mixed-mode I/III loading cases.…”

Section: Introductionmentioning

confidence: 99%

Tensile-Tearing Fracture Analysis of U-Notched Spruce Samples

et al. 2022

View full text Add to dashboard Cite

Spruce wood (Picea Mariana) is a highly orthotropic material whose fracture behavior in the presence of U-shaped notches and under combined tensile-tearing loading (so-called mixed-mode I/III loading) is analyzed in this work. Thus, several tests are carried out on U-notched samples with different notch tip radii (1 mm, 2 mm, and 4 mm) under various combinations of loading modes I and III (pure mode I, pure mode III, and three mixed-mode I/III loadings), from which both the experimental fracture loads and the fracture angles of the specimens are obtained. Because of the linear elastic behavior of the spruce wood, the point stress (PS) and mean stress (MS) methods, both being stress-based criteria, are used in combination with the Virtual Isotropic Material Concept (VIMC) for predicting the fracture loads and the fracture angles. By employing the VIMC, the spruce wood as an orthotropic material is modeled as a homogeneous and isotropic material with linear elastic behavior. The stress components required for calculating the experimental values of notch stress intensity factors are obtained by finite element (FE) analyses of the test configuration using commercial FE software from the fracture loads obtained experimentally. The discrepancies between the experimental and theoretical results of the critical notch stress intensity factors are obtained between −12.1% and −15% for the PS criterion and between −5.9% and −14.6% for the MS criterion, respectively. The discrepancies related to fracture initiation angle range from −1.0% to +12.1% for the PS criterion and from +1.5% to +12.2% for the MS criterion, respectively. Thus, both the PS and MS models have good accuracy when compared with the experimental data. It is also found that both failure criteria underestimate the fracture resistance of spruce wood under mixed-mode I/III loading.

show abstract

“…However, U-and V-shaped notches have been studied much more than the others due to their extensive engineering applications. Several papers have been published in the literature dealing with brittle fracture of U-and V-notched components under pure mode I and pure mode II loadings (e.g., [1][2][3][4][5][6][7][8][9]), as well as under mixed mode I/II loading (e.g., [10][11][12][13][14][15][16]). Different stress-based and energy-based failure criteria have been applied in these works for estimating the brittle fracture conditions in a wide variety of materials containing notches, generating estimations of their corresponding load-carrying capacity (LCC).…”

Section: Introductionmentioning

confidence: 99%

Notch Fracture in Polymeric Specimens under Compressive Stresses: The Role of the Equivalent Material Concept in Estimating the Critical Stress of Polymers

et al. 2021

View full text Add to dashboard Cite

In this paper, the fracture of notched polymeric specimens under compressive stresses was investigated both experimentally and theoretically. In the experimental section, to determine the load-carrying capacity (LCC) of U-notched specimens made of general-purpose polystyrene (GPPS) and polymethyl-methacrylate (PMMA) polymers, tests were performed on notched square samples under compression, i.e., negative mode I loading. In the observation of the nonlinear behavior of the two polymers in the standard compressive tests, for the first time, the equivalent material concept (EMC) was used under compressive loading to theoretically estimate the critical stresses of the two polymers, which were shown to be significantly different from the ultimate strengths obtained from the standard compression tests. By linking the EMC to the maximum tangential stress (MTS) and mean stress (MS) criteria, the LCC of the notched specimens was predicted. The outcomes are twofold: First, MTS, MS, EMC–MTS, and EMC–MS criteria provide accurate predictions of the experimental critical loads observed in the U-notched polymeric specimens; second, the combination of the EMC with the MTS and MS criteria, allow such predictions to be obtained without any need for experimental calibration.

show abstract

Experimental and theoretical fracture assessment of rock-type U-notched specimens under mixed mode I/II loading

Cited by 37 publications

References 55 publications

Influence of testing method on mode II fracture toughness (K_IIc) of hot mix asphalt mixtures

Influence of testing method on mode II fracture toughness (K_IIc) of hot mix asphalt mixtures

Tensile-Tearing Fracture Analysis of U-Notched Spruce Samples

Notch Fracture in Polymeric Specimens under Compressive Stresses: The Role of the Equivalent Material Concept in Estimating the Critical Stress of Polymers

Contact Info

Product

Resources

About

Experimental and theoretical fracture assessment of rock-type U-notched specimens under mixed mode I/II loading

Cited by 37 publications

References 55 publications

Influence of testing method on mode II fracture toughness (KIIc) of hot mix asphalt mixtures

Influence of testing method on mode II fracture toughness (KIIc) of hot mix asphalt mixtures

Tensile-Tearing Fracture Analysis of U-Notched Spruce Samples

Notch Fracture in Polymeric Specimens under Compressive Stresses: The Role of the Equivalent Material Concept in Estimating the Critical Stress of Polymers

Contact Info

Product

Resources

About

Influence of testing method on mode II fracture toughness (K_IIc) of hot mix asphalt mixtures

Influence of testing method on mode II fracture toughness (K_IIc) of hot mix asphalt mixtures