Material library

 

Name of steel fibre concrete

As has been showed before there is a new material type steel fibre concrete. This material is based on library of DRAMIX fibres. The name of fibre concrete is prepared based on the several fibre characteristics and can be as follows:

C28/35-30kg/m3-5D65/60BG

where:

• C28/35 - concrete characteristic
• 30kg/m3 - dosage density, selected from the list
• 5D - type of fibre (3D/4D/5D)
• 65/60 - fibre geometric properties
• BG - fibre production parameters

The name of steel fibre concrete is generated automatically and updated when the following items are changed:

• f_ck of concrete
• dosage amount
• fibre type

The default material database library is prepared based on 3D/4D and 5D fibre concrete.

There is also filter for Steel fibre concrete.

When it is necessary to create completely new material there is also this possibility after click on button New.

Code independent part

Generally there is a group of Code independent items which are common for any kind of material in SCIA Engineer.

Code dependent part

EN 1992-1-1: Steel fibre in compression

This material characteristic are the same as for standard reinforced concrete

Fibres

The definition and selection of fibres is presented in this group. The list of items is the following:

The items above can be explained as follows:

• Selection of fibre type see the list of possible Fibre type - for fibre library see "Fibre library"
• Fibre dosage - edit box for definition of fibre dosage. Generally there is a limit from 20 to 40 kg/m³
• Member size effect - default κ^f_G = 1,7; there will be on factor per material and for slab in fact

• Fibre orientation effect (general) - default κ^f_F = 1,0 - corresponding to bending and tensile loads;

• Fibre orientation effect (shear) - default κ^f_F = 0,5

There is automatic control of fibre type concrete class and dosage. For instance when you define dosage out of range <20;40> then the following message appears

DAfStb: Steel fibre concrete in tension

There are special characteristic per fibre concrete in tension based on amount and type of fibres and concrete class. The procedure of calculation of each values is mentioned in chapter "Materials theoretical background"

ffct0,L1	Characteristic basic residual tensile strength in performance class 1 [MPa]
ffct0,L2	Characteristic basic residual tensile strength in performance class 2 [MPa]
ffct0,u	Characteristic basic residual tensile strength in ULS [MPa]
ffct0,s	Characteristic basic residual tensile strength in SLS [MPa]
εfct,L11	Strain at reaching residual tensile strength in performance class 1 [1e-4]
εfct,L12	Strain at starting descending branch of residual tensile strength in performance class 1 [1e-4]
εfct,L2	Strain at reaching residual tensile strength in performance class 2 [1e-4]
εfc,fctm	Strain at reaching mean concrete tensile strength [1e-4]
εfct,L13	Strain at starting reaching residual tensile strength in performance class 1 [1e-4]
ffctR,L1	Characteristic residual tensile strength in performance class 1 [MPa]
ffctR,L2	Characteristic residual tensile strength in performance class 2 [MPa]
ffctR,u	Characteristic residual tensile strength in ULS [MPa]
ffctR,s	Characteristic residual tensile strength in SLS [MPa]
ffctd,L1	Design residual tensile strength in performance class 1 [MPa]
ffctd,L2	Design residual tensile strength in performance class 2 [MPa]
ffctd,u	Design residual tensile strength in ULS [MPa]
ffctd,s	Design residual tensile strength in SLS [MPa]

Material diagrams

There is possibility to define stress-strain diagram for analysis type independently.

Stress-strain diagram for Linear analysis and Check verification

Stress-strain diagram is one used for linear analysis and check verification. We can focus on two parts:

• compressive part - there are two types of behaviour in compression
  • Bilinear diagram
  • Parabola rectangular diagram

• tensile part - tensile part is prepared automatically based on figure R.2 from [1] DAfStb Guideline "Steel fibre reinforced concrete"

The stress-strain diagram can look as follows for C32/40-30kg/m3-5D65/60GG

Bilinear	Parabola rectangular

Stress-strain diagram for Non-linear analysis

This stress-strain diagram is used for non-linear analysis only. Visibility of this diagram is dependent on setting in project data. There must be selected Functionality > Nonlinearity > Concrete > 2D physical nonlinearity.

Then the following settings "Nonlinear behaviour" is automatically set ON and available for each steel fibre concrete material.

There are several possibilities of definition stress /strain diagram:

• By code without tension part
• By code with tension part and peak - default
• By code with tension part and without peak
• By user definition

The shape of diagram for fibre concrete C30/37-30kg/m3--5D65/60BG is the following:

Diagram type	Diagram
By code without tension part
By code with tension part and peak
By code with tension part and without peak
By user definition - then dialogue for user definition is available where the default can be loaded from selected type of predefined diagram above