Loading rate effect on mixed mode I/II brittle fracture behavior of PMMA using inclined cracked SBB specimen

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:232

Article

Aliha, M. R. M.¹  Samareh-Mousavi, S. S.^1,2  Mirsayar, M. M.³ 

[1] Iran Univ Sci & Technol IUST, Sch Ind Engn, Welding & Joining Res Ctr, Tehran 1684613114, Iran

[2] Iran Univ Sci & Technol IUST, Sch Mech Engn, Tehran 1684613114, Iran

[3] Florida Inst Technol, Dept Aerosp Phys & Space Sci, Melbourne, FL 32901 USA

关键词: Loading rate;    Mixed-mode I;    II fracture;    PMMA;    Fracture criteria;    Variable critical distance;   

DOI  :  10.1016/j.ijsolstr.2021.111177

来源: Elsevier

【 摘 要 】

This paper investigates the effect of loading rate on the mixed-mode I/II fracture behavior of PolymethylMethacrylate (PMMA). Experimental studies are performed using a novel fracture test specimen which has recently been developed, called short bend beam (SBB), in different loading rates of 1 mm/min, 20 mm/min, and 200 mm/min. Fracture test data are presented for pure mode I, pure mode II, and mixed-mode I/II conditions, thanks to the geometrical configuration offered by the specimen covering a full spectrum of mode mixities. Two fracture criteria including maximum tangential stress (MTS), and generalized maximum tangential stress (GMTS) are employed to predict the onset of fracture and the fracture initiation angle in different loading rates. The MTS criterion only considers the singular crack tip terms associated with the stress intensity factors (SIFs) in the solution while the GMTS includes the T stress effect as well as the SIF-related terms. While enhanced predictions provided by the GMTS criterion, as compared to MTS results, reveals the significance of including the T-stress term in the theoretical calculations, the critical distance (rc) is also found as another major parameter playing an important role in the fracture behavior. It is shown that the size of rc decreases by increasing the loading rate. Therefore, for the first time, a variable and loading rate dependent rc value is utilized for employment of the GMTS criterion and it is demonstrated that considering variable critical distance can provide acceptable theoretical predictions for different loading rates. (C) 2021 Elsevier Ltd. All rights reserved.

【 授权许可】

Free