ارزيابي و تحليل ريسك مخاطرات پروژه ي حفاري مكانيزه ي تونل‌ خط 7 متروي تهران با استفاده از روش هاي تصميم گيري چندمعياره

Risk Evaluating for mechanized tunneling in the Tehran Metro-Line 7 by Multi-Criteria Decision-Making Method

مديريت ريسك به عنوان يكي از 12 سطح اصلي مديريت پروژه شناخته مي‌شود، كه از فازهاي شناسايي، ثبت، رتبه‌بندي، شناخت اقدام‌هاي كاهنده، و تخصيص اقدام‌هاي كاهنده ي ريسك تشكيل مي‌شود و مديران پروژه را در اتخاذ شرايط ايمن براي طراحي و اجرا ياري مي‌‌كند. تعدد عوامل مخاطره آميز در پروژه هاي حفاري مكانيزه ي تونل هاي درون‌شهري، رتبه‌بندي ريسك را پيچيده و استفاده از اين شيوه را دشوار مي‌سازند. در اين نوشتار، جهت تحليل ريسك هاي پروژه از روش نزديكي به گزينه ي ايده‌آل استفاده شده است. نتايج حاصل نشان داده است كه ريسك عوامل و عوامل مالي و انساني در رتبه ي اول قرار دارند. همچنين ريسك برخورد با شبكه‌ي قنات‌ها از مهم‌ترين مشكلات در پروژه شناخته شده است. بررسي هاي ميداني صورت‌گرفته از مسير پروژه و با توجه به ريزش هاي اتفاق‌افتاده در محدوده ي خيابان مولوي، كه در اثر برخورد به قنات‌ها و حفره‌هاي ناشناس موجود در مسير پروژه بوده است، صحت آناليزهاي انجام‌گرفته تاييد شده است.

Risk management is today known as one of the nine major project management bodies of knowledge science. An effective risk management allows decision makers to identify the project’s strengths, weaknesses, and opportunities. Also, they will be ready to respond if they arise. It includes identifying, recording, ranking and recognizing of response actions and also allocation of actions to corresponding risks. An appropriate risk management of a project helps project managers in getting safe conditions for project design and implementation. Therefore, one area in which there is a necessary need for decision making is project risk management. One of the main steps in risk management is risk assessment and risk ranking, which are important parts of risk management. On the other hand, tunneling projects are now risk-prone activities in mining engineering context. Missing or incomplete risk management in tunneling projects leads to negative consequences, such as longer project time and increased costs. Due to the multiplicity of risk factors in an urban mechanized tunneling project by Earth Pressure Balance ( EPB ) machine, ranking risk is a complex convoluted procedure. So, it is necessary to use multi-criteria decision-making ( MCDM ) methods. Hence, in this paper, in order to analyze the risks of a tunneling project in Tehran Metro-Line 7, we suggest to use Technique for Order of Preference by Similarity to Ideal Solution ( TOPSIS ) method. It is a method for aggregation that compares a set of alternatives by identifying weights for each criterion. It then normalizes scores for each criterion and calculates the geometric distance between each alternative and the ideal alternative. The obtained results show that financial and human resource factors get the first high risk ranks. Furthermore, the risk of dealing with a network of aqueducts is the most well-known problems of the Tehran Metro-Line 7 project. Conducted field studies of the project and visiting the workshop site confirmed the validity of analysis.