تقويت ديوار برشي فولادي پس از ايجاد گشودگي

Strengthening Steel Shear Wall after Opening Creation

از جمله مزاياي ديوار برشي فولادي، در كنار سرعت و هزينه‌ي ساخت مناسب و همچنين موارد سختي اوليه، مقاومت و شكل‌پذيري بالاي آن، امكان تعبيه‌ي گشودگي در هر محل دلخواه از پانل فولادي است. در اين پژوهش ابتدا ديوارهايي با ضخامت‌ ورق، نسبت ابعاد پانل و درصد گشودگي متفاوت در نرم‌افزار المان محدود آباكوس مدل‌سازي و روابطي كه در گذشته براي تخمين ميزان كاهش سختي و مقاومت ناشي از گشودگي پيشنهاد شده بود، اصلاح شده است. همچنين مشخصات لازم براي المان‌هاي تقويتي به‌گونه‌‌يي تعيين شده است كه رفتار ديوار با و بدون گشودگي تحت بارگذاري مونوتونيك يكسان و روابطي نيز براي اين منظور پيشنهاد شده است. نتايج حاكي از آن است كه در صورت تقويت ديوار با روش پيشنهادي، رفتار ديوار و تنش وارده از ورق به قاب در دو حالت يكسان مي‌شود و مي‌توان از وجود گشودگي صرف‌نظر و ديوار را به روش‌هاي مرسوم مانند روش نواري مدل‌سازي كرد.

In recent years, structures are becoming taller, and high stiffness lateral load resisting systems are needed. Therefore, more attention has been paid to shear walls. In this paper, steel plate shear walls are investigated, which are appropriate in terms of construction speed, cost, high initial stiffness, strength and ductility. A feature of these walls is the capability of being able to create an opening at any location of the wall, due to architectural demands, and some equations have been proposed for estimating the effect of these openings on wall behavior. In this study, the behavior of one-story walls due to monotonic loading has been investigated. At first, we tend to find more complete relations for stiffness and strength reduction. So, walls with moment resisting frames, with minimum stiffness of the boundary elements of the panel (based on AISC’s recommended equation), with 8 different thicknesses for the plate, 5 different panel aspect ratios and 5 different opening percentages (square opening in the middle of the panel) that have been modeled in finite element software, Abaqus, and relations for estimating stiffness and strength reduction due to that opening are proposed. The other purpose of this research is to present a method for strengthening these walls to reach the stiffness and strength of walls without openings after creating the opening; which is mandatory when we decide to create it after its design and construction. So, walls with variable panel openings and dimensions, modeled in software, and their effects, were investigated. It can be concluded from the results that in the case of strengthening a wall with an opening based on the recommended method in this research, the existence of the opening can be ignored and conventional modeling methods for walls without openings can be used. These results are based on monotonic loading of one-story walls, but the cyclic behavior of walls and the effect of moments resulted from multiple stories need further study.