پیوندهای مفید
آمار
| تعداد نشریات | 9 |
| تعداد شمارهها | 446 |
| تعداد مقالات | 5,719 |
| تعداد مشاهده مقاله | 8,018,465 |
| تعداد دریافت فایل اصل مقاله | 6,527,292 |
آزمایش شکافت استوانه بنایی و مدلسازی رفتار محصور شده ملات بر مبنای انرژی شکست | ||
| نشریه مهندسی عمران امیرکبیر | ||
| مقاله 4، دوره 55، شماره 3، خرداد 1402، صفحه 555-582 اصل مقاله (3.49 M) | ||
| نوع مقاله: مقاله پژوهشی | ||
| شناسه دیجیتال (DOI): 10.22060/ceej.2023.21192.7647 | ||
| نویسندگان | ||
| حمید توانایی فر؛ امیرهوشنگ اخویسی* | ||
| دانشکده فنی، دانشگاه رازی، کرمانشاه، ایران | ||
| چکیده | ||
| در این مقاله از تست برزیلی (شکافت) که یک آزمایش نیمه مخرب بوده و حداقل دست خوردگی را در سازه ایجاد می کند، جهت تخمین پارامترهای مقاومتی بنایی های با ملات ماسه و سیمان استفاده می گردد. در این شیوه، به وسیله استخراج مغزه های دارای یک بندِ ملات، و اجرای تست برزیلی تحت زوایای مختلف ملات نسبت به راستای اصلی، می توان پارامترهای مقاومتی بنایی را (c و ) استخراج کرد. این تست را می توان جایگزین مناسبی برای سایر تست های نیمه مخرب خصوصاً تست برش ملات به شمار آورد. تست اخیر نواقصی دارد که عمده آن وجود عدم لحاظ اثر اتساع در ملات است. نقص مذکور، موجب تشدید تنش عمودی موجود بر روی آجر مورد آزمایش شده و در نتیجه مقادیر پارامترهای مقاومتی را بیشتر از مقدار واقعی، برآورد می کند. در ادامه یک ریزمدل پیوسته سه بعدی جهت پیش بینی رفتار بنایی غیرمسلح در فشار، ارائه می گردد. با توجه به تفاوت در مدول الاستیسیته، ضریب پواسون و ضخامت دو مصالح آجر و ملات در بنایی، تلاش های متعددی برای شبیهسازی رفتار فشاری بنایی انجام شده است. برای بررسی این رفتار که تحت تأثیر اندرکنش واحدها و ملات است، مدل های دو بعدی قادر به لحاظ محصورشدگی سه محوره ملات نیستند. از طرفی مدل های سه بعدی موجود به سادگی قادر به کنترل اثر اتساع به صورت صریح و لحاظ محصورشدگی سه محوره نمی باشند. مدل ارائه شده بر مبنای مفهوم ریز صفحه (چند صفحه) است و برای مدلسازی شکست در سازه بنایی در اثر فشار توسعه می یابد. در ادامه توانایی مدل ارائه شده در مقابل نتایج آزمایشگاهی و سایر مدل های عددی، بررسی شده و جهت مدلسازی کار آزمایشگاهی حاضر استفاده میگردد. مقایسه نتایج، دقت مناسب نتایج حاصل از مدل عددی پیشنهادی و قابلیت اجرای تست مغزه در بناییهای آجری با ملات ماسه-سیمان را نشان میدهد. | ||
| کلیدواژهها | ||
| آزمایش مغزه؛ ریز مدلسازی؛ مدل چند صفحهای؛ ملات محصور شده؛ اثر اتساع | ||
| موضوعات | ||
| تحلیل خطی و غیر خطی؛ مکانیک خرابی و پلاستیسیته؛ مکانیک شکست | ||
| عنوان مقاله [English] | ||
| Splitting Test on Masonry Cores and modeling of the Confined mortar behavior based on fracture energy | ||
| نویسندگان [English] | ||
| hamid tavanaeifar؛ Amir Hoshang Akhaveissy | ||
| Department of Civil Engineering, Engineering Faculty, Razi University, Kermanshah, Iran. | ||
| چکیده [English] | ||
| The in situ evaluation of the masonry's mechanical properties is a very complicated task. A viable alternative is based on the use of brick cores including a central mortar layer lying on a symmetry plane. In fact, these specimens can be extracted very easily by cutting cores spanning two bricks at least. The obtained core is then subjected to a splitting test with a setup providing a different inclination of the mortar layer with respect to the loading plane. This type of test is similar to a diagonal wallet test and induces a mixed compression–shear stress state in the central mortar layer. Here, This test is used for masonry with sand and cement mortar. By using a Mohr-Coulomb failure criterion the test result can be interpreted in order to obtain all the mechanical properties of the masonry. This test can be a good alternative to other semi-destructive tests, especially the shove test. The latter test has a defect, that’s due to the lack of effect of dilatancy in the shear behavior of mortar in the shove test, the values obtained in terms of cohesion and friction angle will be greater than the actual value. In the following, a 3D continuous micromodel is presented in order to predict unreinforced masonry behavior. Due to the difference in the modulus of elasticity, the Poisson ratio and the thickness of the brick and mortar, several efforts have been made to simulate the compressive behavior of the masonry using different models with different goals and results. To examine this behavior, which is influenced by the interaction of units and mortar, in one hand, two-dimensional models are not able to consider the 3D confined effect. On the other hand, the three-dimensional models are not able easily to control the effect of 3D confined and dilatation explicitly. The proposed model is based on the concept of micro-plane and is developed to model failure in masonry structures. | ||
| کلیدواژهها [English] | ||
| Core test, Micro modeling, Multi-laminate model, Confined effect, Dilatancy effect | ||
| مراجع | ||
|
[1] E. 1052-3, Methods of test for masonry, in: Determination of initial shear strength, 2002. [2] A. C1531, Standard test methods for in situ measurement of masonry mortar joint shear strength index, in, American Society for Testing and Materials (ASTM) International, 2016. [3] E. Cescatti, M. Dalla Benetta, C. Modena, 16th Analysis and evaluations of flat jack test on a wide existing masonry buildings sample, in: F. Casarin. (Ed.) International Brick & Block Masonry Conference, CRC Press London, , UK, 2016. [4] A. A. Hamid, W. W. El-Dakhakhni, Z. H. Hakam, M. Elgaaly, Behavior of composite unreinforced masonry–fiber-reinforced polymer wall assemblages under in-plane loading, J. Compos. Constr., 9(1) (2005) 73-83. [5] G. Andreotti, F. Graziotti, G. Magenes, Detailed micro-modelling of the direct shear tests of brick masonry specimens: the role of dilatancy, , Engineering Structures 168 (2018) 929–949. [6] A. Brignola, S. Frumento, S. Lagomarsino, S. Podestà, dentification of shear parameters of masonry panels through the in-situ diagonal compression test, International Journal of Architectural Heritage, 3 (2009) 52-73. [7] D. Marastoni, L. Pelà, A. Benedetti, P. Roca, Combining Brazilian tests on masonry cores and double punch tests for the mechanical characterization of historical mortars, Construction and Building Materials 112 (2016) 112-127. [8] L. Pelà, K. Kasioumi, P. Roca, Experimental evaluation of the shear strength of aerial lime mortar brickwork by standard tests on triplets and non-standard tests on core samples, Eng. Struct. , 136 (2017) 441–453. [9] L. Pelà, P. Roca, A. Benedetti, Mechanical characterization of historical masonry by core drilling and testing of cylindrical samples, Int. J. Archit. Heritage, 10(2-3) (2016) 360–374. [10] A. Benedetti, L. Pelà, Masonry properties determination via splitting tests on cores with a rotated mortar layer., in: A. Aprile (Ed.) Proceedings of 8th International Seminar on Structural Masonry,, Istanbul, Turkey, 2008. [11] S. Jafari, J.G. Rots, R. Esposito, Core testing method to assess nonlinear shear-sliding behaviour of brick-mortar interfaces: A comparative experimental study, Construction and Building Materials, 244 (2020) 118-236. [12] J. Dorji, T. Zahra, D. Thambiratnam, D. Lee, Strength assessment of old masonry arch bridges through moderate destructive testing methods, Construction and Building Materials, 278 (2021) 122391. [13] H.K. Hilsdorf, Masonry materials and their physical properties, in: Proc. of the International conference on planning and design of tall buildings, Lehigh University, Bethlehem, Pennsylvania, III, 1972, pp. 981-1000. [14] A. Anthoine, A Homogenisation of periodic masonry: Plane stress, generalised plane strain or 3D modelling? , Comm. Num. Meth. Engrg 13 (1997) 319-326. [15] G. Milani , P.B. Lourenço , A. Tralli, 3D homogenized limit analysis of masonry buildings under horizontal loads, Eng Struct, 29 (2007) 3134–3148. [16] A. J. Aref, K. M. Dolatshahi, A three-dimensional cyclic meso-scale numerical procedure for simulation of unreinforced masonry structures, Computers and Structures, 120 (2013) 9-23. [17] A. Drougkas, P. Roca, C. Molins, Numerical prediction of the behavior, strength and elasticity of masonry in compression, Eng. Struct., 90 (2015b) 15-28. [18] H. Tavanaeifar, A.H. Akhaveissy, 3D Continuos Micro-Model based on Multilaminate Concept for the nonlinear numerical analysis of masonry panels, Amirkabir Journal of Civil Engineering, 53(11) (2022) 22-22.(in persian) [19] ASTM, C496/C496M-17, in: Standard test method for splitting tensile strength of cylindrical concrete specimens, 2017. [20] ASTM E519/E519M-15, Standard test method for diagonal tension (shear) in masonry assemblages, in, 2015. [21] C. Mazzotti, E. Sassoni, G. Pagliai, Determination of shear strength of historic masonries by moderately destructive testing of masonry cores, Constr. Build.Mater., 54 (2014) 421–431. [22] A. C144-11, Standard Specification for Aggregate for Masonry Mortar, in, American Society for Testing and Materials, 2011. [23] ASTM, C348-02, in: Standard Test Method for flexural Strength of Hydraulic Cement Mortars, American Society for Testing and Materials, 2002. [24] A. C109-07, Standard Test Method for Compressive Strength of Hydraulic Cement Mortars, in, American Society for Testing and Materials, American Society for Testing and Materials, 2007. [25] P.B. Lourenco, Computational strategies for Masonry structures, thesis, The Netherlands: Delft University of Technology, 1996. [26] M. Ghadrdan, S.A. Sadrnejad, T. Shaghaghi, Numerical evaluation of geomaterials behavior upon multiplane damage model, Computers and Geotechnics, 68 (2015) 1-7. [27] V. Galavi, H.F. Schweiger, Nonlocal Multi-laminate Model for Strain Softening Analysis, Journal of Geomechanics, ASCE, 1(30) (2010) 1532-3641. [28] A. B. Tsegaye, T. Benz, Plastic flow and state-dilatancy for geomaterials, Acta Geotechnica, 9 (2014) 329-342. [29] M. Petracca, L. Pelà, R. Rossi, S. Zaghi, G. Camata, E. Spacone, Micro-scale continuous and discrete numerical models for nonlinear analysis of masonry shear walls, Constr Build Mater, 149 (2017) 296–314. [30] R. Van Der Pluijm, Shear behavior of bed joints, 6th North American Masonry Conference, 6-9 June 1993, Philadelphia, Pennsylvania, USA, (1993) 125_136. [31] W. He, Y.-F. Wu, K.M. Liew, A fracture energy based constitutive model for the analysis of reinforced concrete structures under cyclic loading, Comput. Methods Appl. Mech. Engrg. , 197 (2008) 4745–4762. [32] Z.P. Bazant, B.H. Oh, Crack band theory for fracture of concrete, RILEM Mater. Struct. Eng., 16 (1983) 155–177. [33] R. Scotta, R. Vitaliani, A. Saetta, E. Oñate, A. Hanganu, A scalar damage model with a shear retention factor for the analysis of reinforced concrete structures: theory and validation, Computers and structures, 79(7) (2001) 737–755. [34] M. Jirásek, M. Bauer, Numerical aspects of the crack band approach, Computers and Structures, 110-111 (2012) 60-78. [35] P.H. Feenstra, R. De Borst, A composite plasticity model for concrete., Int. J. Solids Struct. , 33 (1996) 707–730. [36] A.T. Vermeltfoort, D.R.W. Martens, G.P.A.G.V. Zijl, Brick-mortar interface effects on masonry under compression, Can. J. Civ. Eng., 34 (2007) 1475-1485. [37] B. Karihaloo, Failure of Concrete, in: Comprehensive Structural Integrity, 2003, pp. 477–548. [38] H. Nakamuraa, T. Nanrib, T. Miuraa, S. Roy, Experimental investigation of compressive strength and compressivefracture energy of longitudinally cracked concrete, Cement and Concrete Composites, 93 (2018) 1-18. [39] Y-F. Li, C-T. Lin, Y-Y. Sung, A constitutive model for concrete confined with carbonfiber reinforced plastics, Mechanics of Materials, 35 (2002) 603–619. [40] S. Suriya Prakash, M. Aqhtarudin, J. Suman Dhara, Behaviour of soft brick masonry small assemblies with and without strengthening under compression loading, Materials and Structures, 49 (2016) 2919–2934. [41] B. V. Venkatarama Reddy, Ch. V. Uday Vyas, Influence of shear bond strength on compressive strength and stress–strain characteristics of masonry, Materials and Structures, 41 (2008) 1697–1712. [42] Ch. V. Uday Vyas, B. V. Venkatarama Reddy, Prediction of solid block masonry prism compressive strength using FE model, Materials and Structures, 43 (2010) 719–735. [43] B. Shen, J. Shi, N. Barton, An approximate nonlinear modified Mohr-Coulomb shear strength criterion with critical state for intact rocks, Journal of Rock Mechanics and Geotechnical Engineering, 10 (2018) 645-652. [44] M. H. Motamedi, C. D. Foster, An improved implicit numerical integration of a non-associated, three-invariant cap plasticity model with mixed isotropic–kinematic hardening for geomaterials, 39(wileyonlinelibrary.com) (2015) 1853–1883. [45] Y.G. Zhaoa, S. Lina, Z.H. Lub, T. Saitoa, L. He, Loading paths of confined concrete in circular concrete loaded CFT stub columns subjected to axial compression, Engineering Structures 156 (2018) 21-31. [46] W. Chen, H. Konietzky, C. Liu, H. Fu, J. Zhang., Prediction of Brickwork Failure Using Discrete-Element Method, Journal of Materials in Civil Engineering, 30(9) (2018). | ||
|
آمار تعداد مشاهده مقاله: 806 تعداد دریافت فایل اصل مقاله: 955 |
||