چکیده:
Ganjnameh area is considered an important historical-cultural and touristic place in the west of Iran, seriously threatened by rockfall problems. Attractions of this area yearly attract several thousand visitors from all over the world. Several rockfall events have occurred in the area in the past. Rockfalls occurrences will threaten the life safety of visitors during visiting and surveying of the place. The primary purpose of this research was a preliminary analysis of rockfall potential for the cultural heritage site. For this purpose, an investigation based on three phases was done, which are included: site investigation, laboratory testing, and rockfall simulation. Unstable blocks size, the geometry of slopes, weathering conditions, joint study, and sampling were measured and done during the site investigation phase. Physico-mechanical properties of granite were determined in the laboratory. Total kinetic energy, bounce height, and translational velocity of fallen blocks were determined as rockfall simulation outputs. Based on the obtained result, different mechanisms were found on the left side and right side of the study area. The rockfall problems on the right side could be related to jointing and freezing-thawing action, whereas on the left side, steep slope, weathering, and saturating are the main controlling factors. The results indicated that the footpath between Ganjnameh inscriptions and waterfall, which has a dense concentration of visitors, is subjected to severe problems of rockfall occurrences from both sides, especially the left side. Eventually, for the reduction of rockfall potential and its risk, remedial works are suggested.
منطقه گنج نامه به عنوان یکی از جاذبه های تاریخی-فرهنگی و توریستی در غرب ایران بوده که به شدت به خاطر مشکل سقوط سنگ مورد تهدید قرار دارد. جاذبههای این منطقه باعث جذب هزاران گردشگر در سال از سراسر دنیا میگردد. در گذشته چندین مورد سقوط سنگ در این منطقه روی داده است. رخداد سقوط سنگ می تواند امنیت جانی بازدیدکنندگان را حین بازدید و بررسی این منطقه به خطر بیاندازد. هدف اصلی این تحقیق انالیز مقدماتی از پتانسیل سقوط سنگ در این محل تاریخی میباشد. به همین منظور یک مطالعه بر پایه سه مرحله کاوش صحرایی، انجام ازمونهای ازمایشگاهی و شبیه سازی سقوط سنگ صورت گرفت. در مرحله کاوش صحرایی اندازه بلوکهای ناپایدار، هندسه شیب و شرایط هوازدگی اندازه گیری شده و درزه نگاری و نمونه گیری انجام شد. خصوصیات فیزیکی و مکانیکی گرانیتها در ازمایشگاه تعیین گردید. انرژی کنیتیک کلی، ارتفاع جهش، سرعت انتقالی بلوکهای سقوط کننده به عنوان خروجی شبیه سازی سقوط سنگ تعیین گردیدند. بر پایه نتایج به دست امده، مکانیسم های متفاوتی برای ناپایداری تکیه گاه چپ و راست این منطقه به دست امد. مشکل سقوط سنگ در تکیه گاه راست بیشتر در ارتباط با درزهداری و فرایند یخ زدکی – اب شدگی بوده، در حالی که در تکیهگاه پر شیب سمت چپ فرایند هوازدگی و اشباع شدگی مهمترین فاکتورهای کنترل کننده میباشند. نتایج مشخص نمود که مسیر پیاده رو بین کتیبههای گنج نامه و ابشار که بیشترین تراکم بازدیدکنندگان را نیز دارا میباشد، تحت خطر جدی سقوط سنگ از هر دو تکیه گاه و بخصوص تکیه گاه چپ قرار دارد. در نهایت برای کاهش پتانسیل سقوط سنگ و ریسک ان، روشهای بهسازی پیشنهاد گردید.
خلاصه ماشینی:
2. Associate Professor of Engineering Geology, Faculty of Sciences, Bu-Ali Sina University, Hamedan, Iran Abstract Ganjnameh area is considered an important historical-cultural and touristic place in the west of Iran, seriously threatened by rockfall problems.
Total kinetic energy, bounce height, and translational velocity of fallen blocks were determined as rockfall simulation outputs.
The rockfall problems on the right side could be related to jointing and freezing- thawing action, whereas on the left side, steep slope, weathering, and saturating are the main controlling factors.
(2014) used 2D and 3D rockfall simulation models to measure some characteristics of the fallen blocks such as bounce height, rock velocity, and kinetic energy based on rock position along the slope.
, 2013; Almeida and Kullberg, 2011; Alejano et al.
Based on their results, rockfall was considered the main dangerous slope instability in this area, and many falling blocks can reach the beach threat people in that location.
During the site investigation phase, comprehensive field surveying was done to determine the location of unstable blocks, their volumes and geometries, the key areas prone to the rockfall, geometry of slopes, sampling for laboratory works, weathering evaluation, and joint studies.
A rockfall program was performed and some indices such as total and translational kinetic energy, bounce height, and translational velocity of fallen blocks were determined.
The program will determine some key factors of falling blocks such as velocity, energy, bounce height for the entire slope, and location of rock endpoints.