بررسي مقايسه‌يي و ارايه‌ي پيشنهاد براي بهبود دقت ارزيابي سريع آسيب پذيري لرزه ‌يي ساختمان هاي بنايي

A Comparative Study and Proposal for Enhancement of Rapid Seismic Evaluation of Masonry Buildings

ارزيابي هاي كيفي، كه به ارزيابي سريع نيز معروف هستند، معمولاً براي تعداد زيادي از ساختمان ها تعريف مي شوند. از آنجا كه بايد اطلاعات زيادي در اين روش ها جمع‌آوري شود، نياز به فرم ها و چك ليست هايي است كه براي ساختمان هاي مورد بررسي بايد تكميل شود. در اين نوشتار با توجه به حجم گسترده‌ي ساختمان هاي بنايي و ضعف هاي متداول موجود در آن‌ها، اين نوع ساختمان ها مورد بررسي قرار مي گيرند. دو روش مختلف 154FEMA و نشريه‌ي 376 سازمان مديريت و برنامه‌ريزي كشور براي ارزيابي سريع و تفصيلي تعداد زيادي ساختمان هاي بنايي مدارس با تاكيد بر نشريه‌ي 376 استفاده و اركان هر يك تجزيه و تحليل شده است. نتايج نشان داده است كه هماهنگي مناسبي بين نتايج ارزيابي‌هاي سريع و تفصيلي در نشريه‌ي 376 وجود دارد. همچنين پيشنهادهايي براي اصلاح رابطه‌ي اساسي ارزيابي سريع در نشريه‌ي 376 ارايه شده است، كه به مشابهت كاملي بين نتايج دو نشريه‌ي 376 و 154FEMA انجاميده است.

Among the most suitable methods to obtain building seismic data, in order to specify the level of its seismic vulnerability and prioritize it for undertaking detailed seismic assessment studies, is the use of a qualitative evaluation method. Qualitative evaluation, from this perspective also known as rapid assessment, is usually scheduled for a large number of buildings. Since a huge volume of information has to be collected in such a study, filling special forms and checklists for the studied buildings is necessary. In this paper, considering the great number of masonry buildings and their common weakpoints, this type of building is examined. Two different methodologies, including and Publication No. of the Management and Planning Organization, are used for rapid and detailed evaluation of a large number of school masonry buildings, with emphasis on Publication No. , and a detailed study is accomplished. Actual cases of buildings located in Khuzestan province are considered. The existing condition of these buildings is identified by field surveys and strength-of-material experiments. In addition, two dimensional models of roofs, using the finite element method, and theoretical models for the walls of masonry buildings, are constructed. The joists are modeled with beam elements. For brick arch and joist-and-block roofs, use is made of shell elements. No considerable tensile stresses are observed in the roofs. Then, the lateral loads distributed from the roofs are applied to the walls. For the walls, four failure modes are considered, including mortar joint slippage, overturning, diagonal over-tension, and toe over-compression. It is shown that the rapid and comprehensive evaluation procedures are consistent with Publication No. . Moreover, suggestions are offered to modify the fundamental relationship of rapid assessment in Publication No. , which leads to evaluation results similar to .