#How to apply back pressure plaxis 2d manual#
#How to apply back pressure plaxis 2d pro#

Multiple calculation phases may be created in which different sets of boundary conditions can be specified. The PlaxFlow program offers a convenient option to create circular and non-circular tunnels using arcs and lines. Wells are used to prescribe points inside the geometry model where a specific discharge is subtracted from (sink) or added to (source) the soil.Дrains are used to prescribe lines inside the geometry model where pore pressures are set to zero. An inactive screen is fully permeable (coupling of pore pressure degrees-of-freedom of node pairs). An active screen is fully impermeable (separation of pore pressure degrees-of-freedom of node pairs). Screen elements are used to simulate an impermeable screen. For compatibility with the Plaxis deformation program, 6-node and 15-node elements can also be chosen. PlaxFlow allows for automatic generation of unstructured 2D finite element meshes composed of 3-node triangular elements, with options for global and local mesh refinement. From this geometry model, a 2D finite element mesh is easily generated. The input of soil layers, structures, construction stages and boundary conditions is based on convenient CAD drawing procedures, which allows for a detailed modelling of the geometry cross-section. Groundwater flow applications require advanced models for the simulation of the unsaturated, time-dependent and anisotropic behaviour of soils. This is not the behaviour displayed in PLAXIS 2D 2016.00.PlaxFlow is a finite element package intended for the two-dimensionalВ and staeady-state analyses of saturated and unsaturated groundwater flow problems in geotechnical engineering and hydrology. Similarly, in Figure 2 the axial force should be the lowest at the top and gradually increase downwards due to the self weight of the concrete of the side drift. The correct behaviour should display a bending moment at the top and bottom of the line. In Figure 1 the bending moment line generated from the automatic centerline shows no bending moment at the top and bottom of the side drift, which is incorrect as all connections are rigid in this tunnel case.

#How to apply back pressure plaxis 2d manual#

Incorrect normal force values calculated with automatic centerline (left) and correct values with manual centerline (right) Incorrect bending moments calculated with automatic centerline (left) and correct values with manual centerline (right)ДЇigure 2. In 2016.00, the automatic centerline might not detect the structural forces correctly for an internal tunnel lining connected to concrete elements at the end points.ДЇor example, the axial forces and the bending moments might be incorrect, as shown Figure 1 and Figure 2.ДЇigure 1.

#How to apply back pressure plaxis 2d pro#

Pro tip: Temperature vs time shows latent heat plateau For this tutorial, when pre-selecting a node in the middle of the model, the temperature versus time plot shows the phase change plateau displayed below: Due to the latent heat kicking in, we should see the temperature plateau characteristic of ground freezing. When performing a ground freezing analysis, it is good practice to check that the phase transition from liquid water to ice has been properly triggered. Updated Figure 16.8 for PLAXIS 2D 2016.01 Pro tip Updated Figure 16.7 for PLAXIS 2D 2016.01

Updated Figure 16.6 for PLAXIS 2D 2016.01 They are shown below, and as you can see, they are hardly noticeable. They however bring some slight changes in the results of tutorial 16.

Many improvements have been made to the convection-diffusion implementation, in particular in terms of calculation stability and performance. Updated Figure 15.18 for PLAXIS 2D 2016.01 Tutorial 16: Freeze pipes in tunnel construction Updated Figure 15.17 for PLAXIS 2D 2016.01 See section 2.3 of our document on thermal and coupled THM analysis for more details. The thermal expansion of liquid water plays a role in excess pore pressures and groundwater flow, but not directly in the displacements. In 2016.00, the thermal expansion of water was contributing to the thermal strain of the soil body, which is incorrect: the displacements are only governed by the thermal expansion of the soil skeleton. Tutorial 15: Thermal expansion of a navigable lock