Volume 

A volume corresponds to one casting or is a void used to chamfer or make a hole in another volume.

There are 4 ways to specify the geometry of a volume:

1. As a prism between 2 cross-sections placed respectively at t = 0 and at t = "Length in t-direction". Using cross sections

2. Loading of STL-files in binary or text format (ASCII). Loading STL Model

3. As a confined space defined by its surfaces. Surface model

4. As a confined space defined by its edges. Edge Model

It is also possible to copy volumes based on cross sections or STL Model to a Surface or Edge Model. This allows you to customize the model beyond what the cross-sectional model or STL model allows.

Positioning

The volume is positioned by specifying:

- the origo of the local (r,s,t)-system in the global (x,y,z)-system.

- the direction of t-axis in the (x,y,z)-system.

- the rotation of the (r,s,t)-system around the t-axis. This is done by specifying the "Direction point", P. The (r,s,t)-system is rotated around the t-axis in such a way that the direction point P is in the r-t-plane, with a positive r-coordinate.

Origo of (r,s,t): (x,y,z)=(1.0, 1.0, 1.0); t-vector: (x,y,z)=(0.0, -1.0, 1.0); Direction Point, P: (x,y,z)=(0.5, 0.5, 1.0);

If volumes (which not are voids) are intersecting, the software asks for information about which volume is dominant and which is submissive.

Parameters

The volume can be defined as being a void. The void can intersect more massive volumes.

Voids are useful to make holes and to make chamfers (convex or concave) on non-prismatic volumes.

A massive volume needs a reference to an earlier defined material.

The temperature of the fresh concrete and the time of casting are assigned to the volume.

Al least one volume should be defined from the beginning (Time = 0).

The material properties of hardening concrete are described as a function of maturity. If the maturity of the fresh concrete when casting, is significantly different from the starting point of the function (this is often the time of mixing), then an initial maturity can be indicated. This can apply in situations with a long transport time. The initial maturity is calculated by hand using the formulas in EditMaterial on the time period before casting.

(Hint: The use of the initial maturity increases the consistency between the simulation and the real hardening process. The initial maturity is useful when e.g., having a daily variation in the boundary conditions or changes in the curing measures at specific times. Also, when monitoring temperatures, the use of initial maturity may lead to a better agreement with the simulation. Furthermore, the initial value can also include a contribution from the time used to place the concrete in the volume.)

The variation of temperature, maturity and stress is assumed to be parabolic within each element (tetrahedron). Therefore, the user shall compare the fineness of the mesh with the variation of the temperature/stress-field he/she wants to determine.

If the mesh is too coarse iso-lines are not smooth. In that case the structure should be re-meshed with smaller element-size. However, it should be noted that differences in material properties and concrete age mean that the iso-lines across construction joints do not have to be smooth.

The fineness is defined by the size of the elements at the surface of the volume and the distribution of the fineness towards the core is described by the gradient defined in the “Setup window”.

Volumes in which there are slight variations in temperatures, maturities and stresses can be satisfied with a coarse network (e.g., former hardened concrete volumes and large soil-volumes). If "Coarse Mesh" is checked, the mesh-generator will make a coarse mesh, however under consideration to adjacent structural parts.

If “Self-Weight released at” is checked, it is possible to indicate when the self-weight of the volume is released. This is typically when the formwork is released. The direction of gravity is the opposite direction of the zenith-direction defined in the “Setup” window. When using this facility, it is necessary to define supports or apply external loads which are equilibrating the self-weight, because automatically generated supports are leading to inconvenient results. Read about supports and external loads.

If “Remove volume at” is checked, it is possible to define a time for removal of the volume.

The volume can be deleted.

Trouble-shooting

If a hole is identical to a portion of a massive volume, the software may fail.

The problem can be solved by increasing the size of the hole.

If the corners of a volume are touching another volume on a sloped surface, it could be necessary to increase the number of decimals to establish the construction joint properly.