Features of work of retaining walls made of bored piles in flowing sandy loams

Abstract

The customers usually try to avoid areas with a high groundwater level in the process of choosing a site for construction. The presence of groundwater significantly increases the cost of construction, if there is necessity of the construction of underground floors. But construction in the conditions of modern megacities is increasingly challenging geotechnical engineers, because of the need not only to build on lands with difficult engineering and geological conditions, and not only to develop reliable foundation`s decisions, but also because of the need to more effectively design the underground spaces with its subsequent operation as underground premises for various purposes.The process of water level reducing is not only technologically complex, but also leads to a changes in the physical and mechanical characteristics of soils, which are difficult to predict.This paper shows the features of numerical modeling of walls in water-saturated soils.The effect of the ability to filter water through walls on the stress-strain state of the system of retaining structures – soil mass is demonstrated.The calculations were performed using numerical modeling, since this approach allows engineers to see (predict) the formation of dangerous processes. Numerical modeling also allows to take into account the change in the physical and mechanical characteristics of the soil during drainage of the pit and take into account the process of water level reduction and the effect of water reduction on the formation of the stress-strain state of the system restraining structures – soil mass.In the framework of design process, there is always appear the opportunity to consider various technical decisions for walls and choose the most effective among those considered.In this paper, the construction of walls with the possibility to use the soil berms to temporarily reduce the free height of walls is considered. In addition, the operation of anchor fasteners in soft (weak) soils is shown. Also, elements of the building frame were used to reduce horizontal movements.It is important to understand that not all measures (the construction decisions) are possible in certain conditions, especially when it is a tight environment of dense urban development.