Risk management is an important part of a modern enterprise activity. Currently, risk management should be included in the overall quality management system of a construction organization. Geotechnical construction, for instance, construction of metro, should also be carried out taking into account possible risks. Metro construction is connected with a number of uncertainties related to enclosing rock mass conditions, and specific geotechnical risks, which can lead to materialization of hazards with various consequences. Predicting possible hazards at all stages of a metro structure life cycle requires the ability to manage risks. The effectiveness of risk management requires detailed risk identification, which precedes the stage of determining the probability of risk (the risk assessment stage). To identify an object, it is required to determine its composition, properties, physical origin. The method of such risk cognition with division into groups through determining the essential features (grounds) is classification. To date, different classifications of risks in construction activity have been developed. The paper discusses various approaches to the classification of risks in underground construction, analyzes the feasibility of adapting these classifications to the analysis of geotechnical risks in the construction of metro facilities. The principles of classification of geotechnical risks were proposed. The typology of metro structures has been substantiated as the basis for the classification of geotechnical risks in the construction of metro facilities. The results of the development of a general form for classification of geotechnical risks during a metro construction have been presented.

Risk issues in metro construction should be discussed at the planning and design stages, along with issues of safety, efficiency of technological solutions and reliability. Problems that arise during the construction of an underground facility lead to an increase in time and cost. In the worst case - to the development of various scenarios of emergency situations. These problems are caused mainly by insufficient attention to geotechnical risk management. The effectiveness of this process is related to the quality of risk identification, understanding of the mechanism for developing a risk situation, and the degree of reliability of the risk assessment results. The article presents the results of identification of some geotechnical risks in metro projects in conjunction with risk-forming factors and consequences of their occurrence. A methodic for geotechnical risks assessing, based on an expert-statistical approach is presented, and theoretical generalization is given for individual components of the methodic. The form of information-analytical archive of risks is given. A veracity criteria for the risk assessment is presented. Further development of the approach will allow more reasonable geotechnical risks assessment for decision-making and selecting a program of measures to exclude and minimize the occurrence of risk situations.

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С применением модификации метода «типовых кривых», разработанного для прогноза осадок поверхности над подземными выработками, и с учетом результатов гидрогеологических фильтрационных расчетов проведено комплексное оценивание масштабов карстопроявлений и осадок основания гидротехнического сооружения. Карстовые полости полагаются образующимися вследствие процессов фильтрации воды в растворимой породе, подстилающей грунтовую толщу, на которую опирается фундамент сооружения. С учетом указанных условий предложена состоящая из дугэллипса модель формы сечения полости.Размеры полостей и вызываемые имиосадки поверхности основания оцениваются для различных участков основания с учетом распределения значений скорости фильтрации в породе и данных о переменной мощности защитного слоя глин. Прогнозируемые значения осадок предлагается использовать для обоснования необходимости противокарстовых мероприятий и для районирования их параметров.