Application of modern soil models for numerical calculations of tank bases and foundations

Уже в ближайшем будущем от использования современных численных методов расчета будет зависеть прогресс в области проектирования оснований и фундаментов зданий и сооружений, поскольку возможности по совершенствованию строительных норм практически исчерпаны. Целью статьи является демонстрация возможностей численных расчетов с использованием современных моделей грунта на примере проектирования фундамента стандартного нефтяного резервуара для хранения нефти и нефтепродуктов. Приведено сравнение результатов расчетов осадки основания резервуара емкостью 30 000 м, выполненных в соответствии с действующими нормами проектирования и методом конечных элементов с применением программного комплекса PLAXIS. В частности, проведены численные расчеты с использованием современных моделей грунта: 1) модели грунта с упрочнением (Hardening Soil model, HS); 2) модели грунта с упрочнением и учетом малых деформаций (Hardening Soil small strain model, HSs). Показано, что использование указанных моделей при наличии требуемого объема исходных данных позволяет существенно уточнить вычисления, выполняемые по нормативным методикам. С учетом полученных результатов определена возможность оптимизации проектных решений при выборе типа фундамента резервуара. In the near future, the progress in design of bases and foundations of buildings and structures will depend on the use of modern numerical calculation methods since the opportunities to improve the building regulations are almost exhausted. This article aims to demonstrate the capabilities of numerical calculations with the use of modern soil models on the example of designing the foundation of a standard oil storage tank for crude oil and petroleum products. This article provides a comparison of the results of the base settlement of a 30,000 m tank calculations made in accordance with the current standards of design and the finite elements method with the use of the PLAXIS software package. In particular, the following numerical calculations with the use of modern soil models have been performed: 1) Hardening Soil model, HS; 2) Hardening Soil small strain model, HSs. It is shown that the use of these models in the presence of the required amount of baseline data can significantly refine the calculations performed according to normative methods. Considering the obtained results, the possibility of optimizing design solutions when selecting the type of foundation of a tank was determined.

When physical activity meets the physical environment: precision health insights from the intersection

Background The physical environment can facilitate or hinder physical activity. A challenge in promoting physical activity is ensuring that the physical environment is supportive and that these supports are appropriately tailored to the individual or group in question. Ideally, aspects of the environment that impact physical activity would be enhanced, but environmental changes take time, and identifying ways to provide more precision to physical activity recommendations might be helpful for specific individuals or groups. Therefore, moving beyond a “one size fits all” to a precision-based approach is critical. Main body To this end, we considered 4 critical aspects of the physical environment that influence physical activity (walkability, green space, traffic-related air pollution, and heat) and how these aspects could enhance our ability to precisely guide physical activity. Strategies to increase physical activity could include optimizing design of the built environment or mitigating of some of the environmental impediments to activity through personalized or population-wide interventions. Conclusions Although at present non-personalized approaches may be more widespread than those tailored to one person’s physical environment, targeting intrinsic personal elements (e.g., medical conditions, sex, age, socioeconomic status) has interesting potential to enhance the likelihood and ability of individuals to participate in physical activity.

A Study of Safety Coefficient Determination and Support Parameter Optimization Based on Vulnerability Preevaluation

The preevaluation to the vulnerability of the surrounding rocks is proposed as one of the reliable indicators of the safety coefficient of gateway support and a foundation to optimize the support design parameters. In this study, taking the surrounding rocks, stress, geological environment, and service time into consideration, the safety coefficient is determined based on the vulnerability scores calculated by the vulnerability preevaluation model of the surrounding rock. Applying the safety coefficient to the instability evaluation of the composite rock-bolt bearing structure, the strength required to maintain the stability of the gateway is calculated, which further provides references and guidance to the optimization of the anchor support parameters. This method has been successfully adopted by the GuCheng coal mining project in N1303 tailgate to strengthen the anchor-bolt structure in the roof watering area especially the main inclined shaft. Applying more accurately calculated strength to the anchor-bolt structure can effectively avoid the issue of overcompensation, thus reducing the cost and increasing the driving speed. Furthermore, this method provides insights into optimizing design parameters of the gateway. This method provides a reliable basis for the optimization design of bolt support parameters in coal mine gateway.