Biaxial bending analysis and resistance of generic section with crack width calculation

BiaxialCrack is one of the most advance tool developed by STRUANG. It allows the biaxial bending calculation of complex and generic composite sections with crack width calculation. Starting from a section CAD file (.dxf) user can define the reinforcement, all the embedded profiles and the openings through the concrete. BiaxialCrack studies the section using finite elements by defining a high-level mesh. The software can be used for generic composite material, current version has been written mainly for composite concrete/steel elements. For seismic design it provides Curvature and Ductility calculation (EC2 ITA NTC2018). Once calculation process has been completed user can export all the relevant output in a detailed report (Microsoft Excel and Word document).

Main features:

• complex RC and composite cross-section analysis
• Bending moment Vs curvature diagram, for any direction/any axial force
• 3D Interaction resistance domain (N Mx My)
• 2D interaction resistance domain for each direction (N Mr)
• Linear stress analysis STATE I (un-cracked section, concrete tensile resistance assumed) 
• Linear stress analysis STATE II (cracked section, concrete tensile resistance neglected)
• Non-linear stress analysis STATE III (curvature and elongation defined from non-linear analysis)
• Crack width calculation based on 7.3.4 EN 1992-1-1
• Crack width  3D domain
• Ductility calculation  
• Confinement 
• Staged construction analysis for composite steel-concrete deck
• Prestressed forces calculation
• Eurocode 2 verifications
• Unlimited number of combinations
• Detailed report (Excel and Word)
• Languages: English, German and Italian

BiaxialCrack is a software for the analysis and verification of a generic reinforced section or composite section with a very complex geometry.

BiaxialCrack is very practical for every day design work with simple and clear interface. 

It allows different analysis for a generic reinforced cross-section which may comprises irregular geometry of the concrete area, openings with generic geometry, user defined arrangement of the reinforcement rebars and embedded steel profiles.

Input data

For standard sections, the cross-section geometry can be defined using the interface, while for complex sections directly from CAD drawing (.dxf file). 

BiaxialCrack provides the standard materials but it always allows user defined matrials. 

Uls and sls external forces can be defined on the interface or imported from external .txt file.

Method of analysis and design checks

BiaxialCrack allows user to define different materials stress-strain relationship. For steel the elastic plastic and the elastic plastic with hardening diagrams can be define. For the concrete both linear and parabolic elastic behaviour can defined. We are currently working on a new release which will consider the confinement behaviour of the concrete according to Eurocode 2.

BiaxialCrack stands out because it allows:

• Any type of section geometry (rectangular, polygonal, circular) based on CAD drawing
• Any type of openings with generic geometry
• For rebars
  • No limitation in terms of number of rebar
  • Customisation of rebar diameter
  • Customisation of rebar material properties (i.e. Elastic modulo, resistance and elongations)
• For embedded profiles
  •  Generic section geometry definition based on CAD drawing
  • Customisation of profile material properties (i.e. Elastic modulo, resistance and elongations)

Crack width calculation has been implemented according to EN 1992-1-1:2004 7.3.4 and considering the following parameters:

• For rebars inside tension zone:
• Equivalent diameter
• Rebar spacing
• Cover
• Effective rebars area and stress inside tensile zone
• Eurocode parameters: k1, k2, k3 and k43
• Evaluation of cracked section defining two calculation cases based on rebars spacing

Typical cases studies are represented by the analysis and verification of RC column, beam and bridge pier section.

BiaxialCrack provides several graphs and diagrams output using Matlab libraries.

Output information consists of:

• Figure
  • Section geometry
  • Section mesh
  • Centroid and ellipse of inertia
• Diagrams
• stress strain relations for rebar and matrice material
• 3D interaction domain (N Mx My)
• 2D interaction domain
• Moment Vs curvature diagram
• Stress diagram using colormap for each analysis type and each combination

• Calculation Report
  

  • All mechanical, geometrical, forces and settings assumptions 
  • Geometry information (i.e. reinforcement position, Inertia, neutral axis, etc)
  • Crack width calculation details based on 7.3.4 EN 1992-1-1
  • Maximum and minimum stress for each combination
  • 3D interaction domain points for each orientation defined
    
  • Curvature details with failure tables (yielding and plastic achievement at any curvature).

Comments
The program can easly deal with complex reinforced section geometry throught CAD drawing.
The software establishes a consistent section analysis, stress verification and crack width control in accordance with Eurocode 2.
User can carried out a reinforcement optimisation even though it is not automatic defined on BiaxialCrack. Current version does not includes post tension which is under construction and will be released with next version.

Biaxialcrack has been developed in MATLAB by Ing. Alessandro Angelini (STRUANG).
Copyright : STRUANG Ing. Alessandro Angelini Monteleone di Spoleto ITALY.

BiaxialCrack software. New features for crack control, stress analysis and non linear analysis of moment curvature diagram.

BiaxialCrack - Descrizione breve in Italiano

il software BiaxialCrack nasce per analizzare sezioni complesse costituite da un materiale matrice (che può essere il calcestruzzo oppure il legno) ed uno o più materiali resistenti a trazione (barre in acciaio, barre in fibra e/o profili annegati).
Il calcolo presuppone sempre che le sezioni si mantengano piane e che sussista sempre la perfetta aderenza tra il materiale matrice ed il materiale resistente a trazione. Probabilmente uno dei pochi software, se non l'unico in circolazione, a considerare la presenza combinata di barre di diverso tipo. La versione attuale contempla due differenti materiali per le barre che avviene attraverso il calcolo di due coefficienti di omogeneizzazione per tutti i calcoli proposti.

Le caratteristiche principali del software sono:

• Analisi lineare e non lineare considerando il calcestruzzo reagente a trazione, e considerando il calcestruzzo non reagente a trazione. Quindi inerzie variabili a seconda dello stato di sollecitazione;
• Tracciamento del diagramma momento curvatura con sigma/epsilon calcestruzzo (parabola-rettangolo o lineare) e sigma epsilon acciaio (elasto plastico perfetto o elasto plastico incrudente);
• La geometria delle sezioni può essere definita direttamente sull'interfaccia senza ricorrere a disegni cad per sezioni standard. Per sezioni complesse: qualsiasi forma, vuoti interni qualsiasi, disposizione qualsiasi di armature e profili annegati (a loro volta di geometria qualsiasi);

Video tutorial