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The problem of calculation of reinforced concrete diaphragms is still not resolved and further studies are needed regarding the behaviour of these structures, both in theory and small-scale models, as well as using in situ measurements. The paper gives an overview and comparison of classical and modern methods of assessment of anchorage flexible retaining structures. Method of the soil reaction coefficient kh (Winkler's procedure), and Finite element method (FEM) are discussed. Wall deformations are assumed to follow soil deformation. This means that the elastic line of the wall corresponds to the horizontal soil displacements. Thus, by equalizing these values, their mutual influence can be determined, i.e. wall deformation and soil deformation, defines the distribution of soil pressure on the wall-soil and soil-wall interface. Calculation of the diaphragm wall based on this procedure requires defining the elastoplastic properties of soil under pressure and tension along the diaphragm-soil contact surface. The stress state in soil is determined by the limit equilibrium theory based on Coulomb's law. The basic characteristics of the soil in conditions during construction excavation pit are discussed. The paper presents the empirical and numerical approach to modelling and calculation of anchorage protective structures which is illustrated on the example of simulation of anchorage protective structures using the program Plaxis V8. Thus, an advanced model of constitutional ground is used and compared with the actual results of field measurements of the constructed structure/facility [6]. Furthermore, in parametric study, the influence of changes in cohesion upon horizontal displacements of the diaphragm has been investigated in this paper. Differences between the calculated and measured values of displacement are related to changes in soil cohesion during the individual diaphragm- installation phases. Displacements obtained by measurements are slightly higher than those obtained by calculations, but they have the same 'deflection' shape linearly displaced for a few millimetres, which is a good approximation for practical purposes. |
