Micromechanical Fracture Models of Q345 Steel and Its Weld
Publication: Journal of Materials in Civil Engineering
Volume 31, Issue 11
Abstract
To better predict the ductile fracture of welded joints in steel bridges and buildings under seismic load, the fracture behavior of Q345 steel that has been widely used in China was studied under both monotonic and cyclic loadings based on the microscopic mechanism of material fracture. Based on the results of notched round bar tensile tests and finite-element analyses for Q345 steel base metal, weld metal (transverse and longitudinal), and heat-affected zone specimens, the parameters of the void growth model, stress-modified critical strain model, and cyclic void growth model were calibrated. The parameters of characteristic length in the previous models were determined by scanning electron microscope tests. The results indicated that the toughness parameters of the four materials are significantly different, and the cyclic growth capacity of the voids in weld metal and heat-affected zones deteriorates severely under cyclic loading. The toughness parameters of the two oriented weld metals are similar; therefore, the fracture toughness of the weld metal is less affected by the material orientation. The coefficients of variation of the toughness parameters of the four materials were small, and the distributions of the fracture indexes of the specimens with different notch radii were the same, which proved the effectiveness of the microscopic mechanism fracture model in predicting the initiation of ductile cracks of the members with different geometric shapes and stress states. The results of this paper provide the required material data and model parameters to predict the ductile fracture of welded joints made of Q345 steel using existing micromechanical fracture models.
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Data Availability Statement
Some or all data, models, or code generated or used during the study are available from the corresponding author by request.
Acknowledgments
This research is funded by the National Natural Science Foundation of China (NSFC) (Grants Nos. 51421005 and 51578022). This support is gratefully acknowledged. The results and conclusions presented in the paper are those of the authors and do not necessarily reflect the view of the sponsors.
References
Anderson, T. L. 2005. Fracture mechanics. 3rd ed. Boca Raton, FL: CRC Press.
Chi, W. M. 2000. “Prediction of steel connection failure using computational fracture mechanics.” Ph.D. dissertation, Dept. of Civil and Environmental Engineering, Stanford Univ.
Chi, W. M., G. G. Deierlein, and A. Ingraffea. 2000. “Fracture toughness demands in welded beam-column moment connections.” J. Struct. Eng. 126 (1): 88–97. https://doi.org/10.1061/(ASCE)0733-9445(2000)126:1(88).
Connor, R. J., and J. W. Fisher. 2006. “Consistent approach to calculating stresses for fatigue design of welded rib-to-web connections in steel orthotropic bridge decks.” J. Bridge Eng. 11 (5): 517–525. https://doi.org/10.1061/(ASCE)1084-0702(2006)11:5(517).
Deng, Y., Y. Liu, D. Feng, and A. Li. 2015. “Investigation of fatigue performance of welded details in long-span steel bridges using long-term monitoring strain data.” Struct. Control Health Monit. 22 (11): 1343–1358. https://doi.org/10.1002/stc.1747.
Fisher, J. W. 1984. Fatigue and fracture in steel bridges: Case studies. New York: Wiley.
Hancock, J. W., and A. C. Mackenzie. 1976. “On the mechanisms of ductile failure in high-strength steels subjected to multi-axial stress-states.” J. Mech. Phys. Solids. 24 (2–3): 147–160. https://doi.org/10.1016/0022-5096(76)90024-7.
Hibbitt, H., B. Karlsson, and P. Sorensen. 2011. ABAQUS analysis user’s manual, version 6.10. Providence, RI: Dassault Systèmes Simulia.
Kanvinde, A. M. 2004. “Micromechanical simulation of earthquake-induced fracture in steel structures.” Ph.D. dissertation, Dept. of Civil and Environmental Engineering, Stanford Univ.
Kanvinde, A. M., and G. G. Deierlein. 2006. “Void growth model and stress modified critical strain model to predict ductile fracture in structural steels.” J. Struct. Eng. 132 (12): 1907–1918. https://doi.org/10.1061/(ASCE)0733-9445(2006)132:12(1907).
Kanvinde, A. M., and G. G. Deierlein. 2007. “Cyclic void growth model to assess ductile fracture initiation in structural steels due to ultra low cycle fatigue.” J. Eng. Mech. 133 (6): 701–712. https://doi.org/10.1061/(ASCE)0733-9399(2007)133:6(701).
Kanvinde, A. M., B. V. Fell, I. R. Gomez, and M. Roberts. 2008. “Predicting fracture in structural fillet welds using traditional and micromechanical fracture models.” Eng. Struct. 30 (11): 3325–3335. https://doi.org/10.1016/j.engstruct.2008.05.014.
Keating, P. B., and J. W. Fisher. 1986. Evaluation of fatigue tests and design criteria on welded details. Bethlehem, PA: Fritz Engineering Laboratory, Lehigh Univ.
Lemaitre, J., and J. L. Chaboche. 1990. Mechanics of solid materials. Cambridge, UK: Cambridge University Press.
Liao, F., W. Wang, and Y. Chen. 2012. “Parameter calibrations and application of micromechanical fracture models of structural steels.” Struct. Eng. Mech. 42 (2): 153–174. https://doi.org/10.12989/sem.2012.42.2.153.
Matos, C. G., and R. H. Dodds. 2001. “Probabilistic modeling of weld fracture in steel frame connections. Part I: Quasi-static loading.” Eng. Struct. 23 (8): 1011–1030. https://doi.org/10.1016/S0141-0296(00)00107-3.
Matos, C. G., and R. H. Dodds. 2002. “Probabilistic modeling of weld fracture in steel frame connections. Part II: Seismic loading.” Eng. Struct. 24 (6): 687–705. https://doi.org/10.1016/S0141-0296(01)00133-X.
McClintock, F. A. 1968. “A criterion for ductile fracture by the growth of holes.” J. Appl. Mech. 35 (2): 363–371. https://doi.org/10.1115/1.3601204.
Norris, D. M., J. E. Reaugh, B. Moran, and D. F. Quinones. 1978. “Plastic-strain, mean-stress criterion for ductile fracture.” J. Mater. Sci. Technol. 100 (3): 279–286. https://doi.org/10.1115/1.3443491.
Panontin, T. L., and S. D. Sheppard. 1995. “The relationship between constraint and ductile fracture initiation as defined by micromechanical analyses.” In Fracture mechanics: 26th volume: ASTM STP 1256, 54–85. West Conshohoken, PA: ASTM.
Rice, J. R., and D. M. Tracey. 1969. “On the ductile enlargement of voids in triaxial stress fields.” J. Mech. Phys. Solids 17 (3): 201–217. https://doi.org/10.1016/0022-5096(69)90033-7.
Righiniotis, T. D., and R. E. Hobbs. 2000. “Fracture strength of a moment resisting welded connection under combined loading: Part II—Results.” J. Constr. Steel. Res. 56 (1): 31–45. https://doi.org/10.1016/S0143-974X(99)00101-7.
Righiniotis, T. D., E. R. Lancaster, and R. E. Hobbs. 2000. “Fracture strength of a moment resisting welded connection under combined loading: Part I—Formulation.” J. Constr. Steel. Res. 56 (1): 17–30. https://doi.org/10.1016/S0143-974X(99)00100-5.
Rousselier, G. 1987. “Ductile fracture models and their potential in local approach of fracture.” Nucl. Eng. Des. 105 (1): 97–111. https://doi.org/10.1016/0029-5493(87)90234-2.
SAC (Standardization Administration of the People’s Republic of China). 2008. Code for high strength low alloy structural steel. [In Chinese.]. Beijing: SAC.
Shi, Y., M. Wang, and Y. Wang. 2011. “Experimental and constitutive model study of structural steel under cyclic loading.” J. Constr. Steel. Res. 67 (8): 1185–1197. https://doi.org/10.1016/j.jcsr.2011.02.011.
Shi, Y., M. Wang, and Y. Wang. 2012. “Experimental study of structural steel constitutive relationship under cyclic loading.” [In Chinese.] J. Build. Mater. 15 (3): 293–300. https://doi.org/10.3969/j.issn.1007 9629.2012.03.001.
Ya, S., K. Yamada, and T. Ishikawa. 2011. “Fatigue evaluation of rib-to-deck welded joints of orthotropic steel bridge deck.” J. Bridge Eng. 16 (4): 492–499. https://doi.org/10.1061/(ASCE)BE.1943-5592.0000181.
Yan, F., W. Chen, and Z. Lin. 2016. “Prediction of fatigue life of welded details in cable-stayed orthotropic steel deck bridges.” Eng. Struct. 127 (Nov): 344–358. https://doi.org/10.1016/j.engstruct.2016.08.055.
Zener, C., and J. H. Hollomon. 1944. “Effect of strain rate upon plastic flow of steel.” J. Appl. Phys. 15 (1): 22–32. https://doi.org/10.1063/1.1707363.
Zhou, H., Y. Wang, Y. Shi, and J. Xiong. 2015. “Fracture analyses of welded details in beam-to-column connections using micromechanics-based models.” [In Chinese.] Eng. Mech. 32 (5): 37–50. https://doi.org/10.6052/j.issn.1000-4750.2013.11.1088.
Zhou, H., Y. Wang, L. Yang, and Y. Shi. 2014. “Seismic low-cycle fatigue evaluation of welded beam-to-column connections in steel moment frames through global-local analysis.” Int. J. Fatigue 64 (Jul): 97–113. https://doi.org/10.1016/j.ijfatigue.2014.03.002.
Zong, L. 2015. “Investigation on fatigue crack propagation and life prediction of steel bridges based on fracture mechanics.” [In Chinese.] Ph.D. dissertation, Dept. of Civil Engineering, Tsinghua Univ.
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©2019 American Society of Civil Engineers.
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Received: May 20, 2018
Accepted: May 29, 2019
Published online: Aug 26, 2019
Published in print: Nov 1, 2019
Discussion open until: Jan 26, 2020
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