ارزیابی عملکرد طاق‌های بنایی سنتی غیرمسلح تحت بارهای جانبی

نوع مقاله : پژوهشی اصیل (کامل)

نویسندگان
گروه مهندسی زلزله و ژئوتکنیک، دانشکده مهندسی عمران و نقشه‌برداری، دانشگاه تحصیلات تکمیلی صنعتی و فناوری پیشرفته، کرمان، ایران
چکیده
امروزه حفظ و نگهداری از سازه‌های بنّایی در مناطق تاریخی، اهمیت زیادی پیدا کرده است. بخش قابل توجهی از این مسئله ناشی از کاربرد مصالح بنایی غیرمسلح در ساخت بسیاری از این گونه از سازه‌ها است. در کشور ایران، اکثر بناهای تاریخی نیز با استفاده از مصالح بنایی و با معماری خاص این منطقه احداث شده‌اند. سازه‌های موجود، اکثراً شامل دیوارهای بنایی پیوسته و بعضاً با بازشوهای قوسی شکل هستند. در این گونه از دیوارها، سازه شامل دو پایه و یک قوس در بالای آن است. از آنجایی که ایران در منطقه لرزه خیزی واقع شده است، بررسی عملکرد این سازه‌ها در برابر زلزله و بارهای جانبی، اهمیت زیادی دارد. از این رو، در این مقاله، به بررسی عددی رفتار درون صفحه طاق‌های آجری سنتی در مقابل بارهای جانبی پرداخته می‌شود. در این راستا، مدل عددی از نمونه‌ای از طاق‌های موجود (در بازار مسگرهای کرمان)، تحت شدت‌های بار پیش فشرده سازی (ثقلی) مختلف قرار گرفته و سپس، تحت بار افزون و به صورت جانبی (تحلیل پوش اُور) تحلیل می‌شود و پاسخ نیروی برشی-تغییرمکان آن استخراج می‌گردد. سپس نمودار به دست آمده دوخطی شده و بر اساس آن، نقاط عملکردی آن استخراج می‌شوند. بر اساس نتایج به دست آمده از تحلیل مشاهده گردید که با افزایش شدت بار ثقلی، ظرفیت برشی بیشینه دیوارها نیز افزایش پیدا می‌کند. اما افزایش بیش از حد بار ثقلی منجر به آسیب دیدگی طاق تحت اثر بار ثقلی شده که به موجب آن، سیر افزایشی ظرفیت برشی روند معکوس به خود می‌گیرد. همچنین، الگوی توزیع ترک و خسارت در طاق‌ها کمابیش مشابه هم بوده اما میزان بازشدگی ترک‌ها به شدت از میزان بار ثقلی وارد بر سازه دیوار تأثیر می‌پذیرد.

کلیدواژه‌ها

موضوعات


عنوان مقاله English

Performance Assessment of Unreinforced Masonry Arched walls Under the Action of Lateral Loading

نویسندگان English

F. Homaei
E. Vosoughi Rahbari
Department of Earthquake and Geotechnical Engineering, Faculty of Civil and Surveying Engineering, Graduate University of Advanced Technology, Kerman, Iran
چکیده English

In today's, the preservation and maintenance of masonry structures in historical areas have become very important. A significant part of this issue is rooted in the use of non-reinforced construction materials in the building of such structures. In Iran, most of the historical buildings were built using masonry materials. The buildings were designed according to the special architecture of this region. The existing structures mostly consist of masonry walls as well as some openings with arched configurations. In these types of walls, the wall consists of two piers and an arch on top of them. Since Iran is located in a highly seismic zone, investigating the performance of these types of structures is essential under the action of earthquakes and lateral loadings. Therefore, in this paper, a numerical investigation is accomplished on the in-plane behavior of traditional brick arches under the action of lateral loads. To this end, the numerical model of a sample of an existing arch (in Kerman’s Mesgari bazaar) was considered. The model was developed on STKO software. In this regard, the nonlinear response of bricks and mortar joints was simulated by using the DamageTC3D material. As well, the geometry of the wall was constructed with four-node plane-stress elements. The lateral capacity of the wall was assessed under the action of gravity loads. To this end, the wall was analyzed under gravity loads with intensities of 0.0 to 0.2 MPa. Next, it was pushed laterally through the pushover analysis and the shear force-displacement capacity curve of the wall was obtained. Through a specific procedure, the obtained capacity curves were estimated with a bilinear graph. By using this graph, the performance points corresponding to the wall’s capacity were extracted and a complete discussion was made regarding the shear capacity and the corresponding displacement to each performance point. Based on the obtained results from the analysis, it was observed that with an increase in the intensity of the applied gravity load, the maximum shear capacity of the walls increases. However, a higher increase in gravity load intensity (over a specific limit) would cause more damage to the arch which leads to a smaller shear capacity. Also, it is observed that the distribution of cracks and their pattern along the walls follow a similar outline. However, crack widths are affected strongly by the intensity of the applied gravity load on the wall.

کلیدواژه‌ها English

Unreinforced Masonry Walls
Masonry arches
pushover analysis
In-plane behavior
Pre-compression load
Shear capacity
[1] Howlader MK, Masia MJ, Griffith MC. Numerical analysis and parametric study of unreinforced masonry walls with arch openings under lateral in-plane loading. Engineering Structures. 2020;208:110337.
[2] Karimi AH, Karimi MS, Kheyroddin A, Shahkarami AA. Experimental and Numerical Study on Seismic Behavior of An Infilled Masonry Wall Compared to An Arched Masonry Wall. Structures. 2016;8:144-53.
[3] Hwang S-H, Kim S, Yang K-H. In-plane lateral load transfer capacity of unreinforced masonry walls considering presence of openings. Journal of Building Engineering. 2022;47:103868.
[4] Belghiat C, Plassiard J-P, Messabhia A, Plé O, Guenfoud M. Analytical and numerical study of double-panel confined masonry walls. Journal of Building Engineering. 2021;39:102322.
[5] Pereira JM, Correia AA, Lourenço PB. In-plane behaviour of rubble stone masonry walls: Experimental, numerical and analytical approach. Construction and Building Materials. 2021;271:121548.
[6] Farahani EM, Yekrangnia M, Rezaie M, Bento R. Seismic behavior of masonry walls retrofitted by centercore technique: A numerical study. Construction and Building Materials. 2021;267:120382.
[7] Bianchini N, Gaetani A, Mendes N, Lourenço PB. Experimental Behaviour of Masonry: Static and Dynamic Behaviour of Arches and Vaults. In: Milani G, Sarhosis V, editors. From Corbel Arches to Double Curvature Vaults: Analysis, Conservation and Restoration of Architectural Heritage Masonry Structures. Cham: Springer International Publishing; 2022. p. 79-121.
[8] Nikooravesh M, Soltani M. Experimental and analytical investigation of seismic behavior of centercore-retrofitted masonry walls. Engineering Structures. 2021;244.
[9] Xu W, Zhang T, Chen X, Miao Q, Wang S, Du D. Experimental and numerical investigation on the seismic performance of masonry walls reinforced by PC panels. Journal of Building Engineering. 2022;58:105049.
[10] Tarque N, Manchego A, Lovón H, Blondet M, Varum H. Experimental in-plane behaviour and drift-based fragility assessment of typical Peruvian confined masonry walls. Construction and Building Materials. 2022;341:127893.
[11] Pradhan B, Zizzo M, Sarhosis V, Cavaleri L. Out-of-plane behaviour of unreinforced masonry infill walls: Review of the experimental studies and analysis of the influencing parameters. Structures. 2021;33:4387-406.
[12] Xin R, Ma P. Experimental investigation on the in-plane seismic performance of damaged masonry walls repaired with grout-injected ferrocement overlay. Construction and Building Materials. 2021;282:122565.
[13] Camata G, Marano C, Sepe V, Spacone E, Siano R, Petracca M et al. Validation of non-linear equivalent-frame models for irregular masonry walls. Engineering Structures. 2022;253:113755.
[14] Tomazevic M. Earthquake-resistant design of masonry buildings: World Scientific; 1999.
[15] Preciado A, Peña F, Colmenero Fonseca F, Silva C. Damage description and schematic crack propagation in Colonial Churches and old masonry buildings by the 2017 Puebla-Morelos earthquakes (Mw = 8.2 and 7.1). Engineering Failure Analysis. 2022;141:106706.