b4cast - Simulation of Hardening Concrete

The b4cast is advanced software for simulating the temperatures and stresses in 3-dimensional concrete structures during hardening. By means of the software, structures are modeled for different construction methods in order to optimize the solution.

It is very important to be careful about the hardening process of concrete. Inappropriate construction methods can cause:

Freezing before the concrete is strong enough
Too early evaporation leading to a weak cover layer
Too high temperature differences leading to crack-formation
Lack of final strength due to too high temperatures
Lack of strength at form-removal, prestressing or loading

In all cases the concrete structure will be directly damaged and the durability, functionality and appearance will be substantially reduced. On the other hand it is also important not to make more arrangements than necessary. By making a simulation prior to start-up of a project the risk of damages are reduced or eliminated.

The b4cast software is useful for:

Contractors, in planning construction methods fulfilling requirements and economy limitations.
Consultants, during the design-phase where it is possible to check the planned activities.
Precast industries, optimizing the production

Before the execution, you can choose a construction method which is satisfying requirements concerning:

- max. temperature
- differences in temperatures
- strength (based on maturity)
- curing (including rate of evaporation or total evaporation)
- freezing
- maximum exploitation of tensile strength (crack-formation)

By means of b4cast you can describe your 3D-dimensional structure and try different construction methods in order to get an optimum solution regarding quality, time and money.

Since b4cast is based on the Finite Element Method and is modeling in 3D, a wide range of problems can be solved.

The computer-program is very user-friendly. No in-depth knowledge about the Finite Element Method is required. What is needed is to describe the construction method, start the calculation and check if the results are reasonable.

Construction Method

Volumes corresponding to actual castings or other structural parts are defined geometrically. Geometries can be specified directly in the software or STL files can be imported.

Time of casting and the casting temperature are defined.

Temporary (supporting) structural volumes can be removed during the simulation.

Modelling of cooling pipes/heating wires is possible.

Materials

The hardening concrete is described by:

Activation Energy/Datum Temperature/Ref. Temperature
The Heat of Hydration
Cement Content
Heat Capacity
Density
Thermal Conductivity
E-modulus
Poissons ratio
Thermal expansion
Eigen-strain
Creeping
Tensile Strength
Compression Strength

Maturity is based on Arrhenius or Nurse-Saul functions.

Materials can be imported from and exported to libraries. In this manner the same material can be reused in different jobs. Together with the software are delivered examples on materials, which are ready to use.

Thermal Boundaries

The following models can be assigned to surfaces:

Temperature related to convection
Wind-speed
Shields: user defined formwork/insulation etc.
Flux
Temperature related to radiation
Transmission coefficient related to radiation
Heat from evaporation/condensation

All models are functions of time.

Internal heating or cooling can be done by specifying heating cables or cooling pipes (open circuits, closed circuit and cooling plants can be specified).

Shields can be imported from and exported to libraries. In this manner the same shield can be reused in different jobs. Together with the software are delivered examples on shields, which are ready to use.

Displacement boundaries

The structure can be provided with displacement boundaries in relation external restraints. Displacement boundaries are also used in specifying planes of symmetry.

If none or some displacement boundaries are supplied by the user the software automatically complement boundaries in a way, which makes the structure statically determinate. Self-weight and external loads are considered.

The connection between two adjacent volumes can be decoupled. Decoupling is used to model construction joints where one or more displacement components are discontinuous. It can be, for example, a soft joint or related to match casting operations of precast segments. Decoupling is also useful if there is no mechanical interaction with e.g., a ground volume, but still thermal interaction.

Calculation Method

The analyses (thermal- and stress-) are performed by means of the Finite Element Method. The structure is meshed into tetrahedrons. The variation of temperature, maturity and stress within the element is assumed to be parabolic within each element..

Stress Analysis

The mechanical properties of the materials are assumed to be within the linear-elastic strain range.

In practice, this means that the stresses in a structure are not redistributed, for example if the tensile stresses exceed the tensile strength of the material, during the simulation.

In that case, the stresses are no longer accurate but indicate that cracks will occur.

Based on this, curing measures can be revised to achieve a crack-free structure through renewed simulation.

In construction joints and other connections, such as between concrete and steel forms, the interaction is assumed to be perfect (unless they are modeled as uncoupled).

There will be no separation or sliding at the interface between the two construction parts during the simulation.

If it is assessed from an initial analysis that, for example, a cylindrical steel form will detach from a cast column during the curing process (due to thermal contraction and/or autogenous shrinkage), the steel form can be removed at that time and no longer interact with the concrete column.

The creep strains are also assumed to be within a range where the creep properties can be considered linear.

Results

Results are:

Temperatures
Maturities
Tensile and compression strengths
Amount of evaporated/condensed water from surfaces
Stresses, Principal Stresses and exploitation of tensile strength
Strains, Principal Strains
Displacements
3D Deformations

Results variation in space are presented as contour plots in user-defined sections

Results variation in time are presented as graphs with minimum/maximum-values, average values, or values in user-defined points.

Cross-sections with extreme values can automatically be located.

Licensing

The b4cast software is available with a time-limited license.

The software and license are provided over the Internet.

Free trial

Product	Annual license ¹⁾	Monthly license ¹⁾
Thermal analysis only	1500 USD	200 USD
Thermal analysis + Stress analysis	3000 USD	400 USD
E-mail support during license period ²⁾	2250 USD	400 USD
¹⁾ A fee of 4% will be added on to any payment made with a credit card at time of the sale. No extra fee is charged for bank wire transfer. ²⁾ Alternatively, support can be purchased on hourly basis.

All prices are exclusive VAT, taxes, and duty.

Please state payment method when placing order (bank wire transfer or credit card).

Order

System Requirements

The license requires access to the Internet.

Operative systems: Windows

Thermal Analysis: min. 4 GB RAM

Stress Analysis without cooling pipes/heating cables: min. 8 GB RAM

Stress Analysis with cooling pipes/heating cables: min 16 GB RAM

Vertical display resolution of minimum 900