Continuous beams

Continuous beams is a program that has been conceived to analyse, design and check continuous beam alignments of frames made out of concrete, and rolled, welded and cold-formed steel (with various floor slab arrangements) based on the introduced geometry of the alignment and loadcase of the acting forces. The program offers detailed ultimate limit state check reports and detailed drawings containing the corresponding reinforcement detailing.

Types of beams resolved and floor slab dispositions

Continuous beams resolves the following types of beams:

Concrete beams

  • Flat beams
    • Flat rectangular beam
    • Flat ‘T’ beam
    • Flat beam with right flange
    • Flat beam with left flange
  • Dropped beams
    • Dropped rectangular beam
    • Dropped rectangular beam with collaborating head
    • Inverted rectangular beam
    • Dropped ‘T’ beam
    • Dropped ‘T’ beam with embedded flange
    • Inverted ‘T’ beam with embedded flange
    • Inverted ‘T’ beam
  • Lattice beams
    • Flat rectangular lattice beam
    • Flat ‘T’ lattice beam
    • Flat rectangular lattice beam with right flange
    • Flat rectangular lattice beam with left flange
    • Dropped rectangular lattice beam
  • Beams with external fixity
    • Masonry wall support
    • Wall support
    • Fixed support
  • Prestressed beams
    • Prestressed rectangular flat beam
    • Prestressed flat ‘T’ beam
    • Prestressed flat beam with right flange
    • Prestressed flat beam with left flange
  • Foundation beams
    • Rectangular foundation beam
    • Flat foundation beam
    • Inverted ‘T’ foundation beam
    • Foundation beam with right flange
    • Foundation beam with left flange

The floor slab dispositions which can be introduced with concrete beams are:

  • Exempt beam
  • Floor slabs at the same level
  • Floor slabs with elevation change
  • Intersection of sloped slabs (ridge/valley)
  • Intersection at the eave of sloping roof

Steel beams

The program allows for the introduction of rolled, welded and cold-formed steel sections which are managed from its wide database composed of a large variety of sections. Sections can be created by users consisting of the simple section with a welded connection, lateral plates, batten plates, etc. Sections with varying depth can be defined as can non-composite castellated beams with hexagonal, octagonal or circular openings. The program carries out the fire resistance check and designs the protective cover for the steel sections.

The floor slab dispositions which can be introduced with steel beams are:

  • Exempt beam
  • Beam with floor slab at one or both sides
    If floor slabs are present at both sides, their depth may differ, however both must be situated at the same level.

Data introduction

The program has two data introduction assistants, one which is executed when a new job is created and another to generate beam alignment with the job.

Assistant for general data introduction of a new job

This assistant is executed when a new job is created by the user, having indicated its name and description. This assistant requests the following data from the user:

  • Design codes
    The user has to indicate the concrete, rolled and cold-formed steel codes which are to be used.
  • Concrete
    • Materials
      The user has to define the type of concrete and reinforcement steel to be used in the floor slabs and foundations.
    • Environment
      The exposure class is defined, and if required, the specific exposure class.
    • Deflection limits
      • Instantaneous, by type of simple loadcase
      • Instantaneous, by type of load combination
      • Long term, by type of load combination
      • Long term active, by type of load combination
        Users can import the deflection limits stated in the selected concrete code. This is possible by selecting the Design conditions button (blue arrow situated on the right), whereby a dialogue box will appear providing information on the deflection limits which will be applied if the dialogue box is selected and depend on the selected concrete code.
    • Fabrication loss
  • Rolled steel
    • Type of steel
    • Deflection limits
      As occurs with concrete, the user defines the deflection limits and has a button in the top right-hand corner of the dialogue box where the deflection limits in accordance with the selected rolled steel code can be obtained and configured.
    • Fire situation
      Activates the fire resistance check.
  • Cold-formed steel
    Contains the same options as for rolled steel.
  • Combinations
    In this section, the combinations which are going to be carried out by the program can be consulted. Users can also create their own combinations by pressing on Configure combinations for each limit state.
  • Loadcase
    Here the user indicates the use category and various loadcases the beam alignments to design are going to have.
  • Loadcase consideration for deflection calculation
    The instant when falsework is removed, the load percentage and the instant at which the load is applied for the loadcases defined in the previous section.

Assistant for creating a frame with equal beams

Having finished using the previous assistant, users can define the alignments in the job. To do so, click on the Frames of the job button (), which will allow for one or several beam alignments to be defined with the same properties for each span using the Assistant for creating a frame with equal beams. Once the user has finished using the assistant, the data that has been introduced can be edited and the properties of each span (span length, loads, type of beam, type of floor slab...) can be modified.

The stages for which the assistant asks for beam alignment data are as follows:

  • Description
    • Frame reference
    • Number of beams
    • Free span of each beam
  • Transverse section
    The type of beam and the dimensions of the transverse section are indicated here. More information on the types of beams and floor slabs reaching the beam can be found in Types of beams resolved and floor slab arrangements.
  • Floor slabs
    The floor slab arrangements at either side of the beam are indicated here. More information on the types of beams and floor slabs reaching the beam can be found in Types of beams resolved and floor slab arrangements.

Program environment. Edit data introduced by the assistants

Once the work using the two assistants has been completed, users can edit all the data.

This is possible using the buttons or drop-down menus (all situated at the top part of the program screen).

  •   File menu
  • Job data menu
    • Beam general data
      Allows the user to edit the general data of the concrete beams, rolled steel beams and cold-formed beams of the job.
      • Materials
      • Environment
      • Deflection limits
      • Fabrication loss (only for concrete beams)
      • Fire situation (only for steel beams)
    •  Combinations
      Allows the user to consult the combinations which are going to be carried out by the program. The user can also create his/her own combinations by pressing the Configure combinations for each limit state button.
    • Loadcase
      Here, the user can edit the use category and loadcases the beam frames of the job are going to have.
    •  Loadcase consideration for deflection calculation
      The instant at which the falsework is removed, the load percentage and application instant of the different loadcases defined in the previous section (Loadcase).
    •  Design options
      Here, the user can edit the general program options, such as reinforcement tables, element libraries, check and design options, etc.
    •  Frame creation and selection
      Using these tools, users can open the dialogue box to add, delete or copy alignments which have already been introduced and select the alignment to be edited.
    •  Edition of the geometry and loads of the selected frame
      Opens a window in which the user can edit the spans, sections, loads and environment conditions of the beams making up the selected frame.

      Elevation changes for each beam of the alignment can be introduced in this window ( button) and beams with a variable section ( button). If different elevation changes are introduced at the initial and final ends, this will result in a sloped beam.
    •  Reinforcement edition and results consultation of the selected frame
      Edits the resistance elements included in the selected frame: reinforcement, steel sections, infills, lattices, connectors, etc.
    •  Check
      Verifies all the geometry and reinforcement prescriptions stated in the selected code. The reinforcement can be introduced or designed. The reinforcement can be modified and then checked to see whether it fails. Therefore, users can verify that the geometry of the element and the reinforcement provided comply with all the limitations. It respects the reinforcement that has been introduced and does not redesign it. The checks carried out include those of the corresponding code, criteria from various authors and other criteria provided by CYPE. The user design options are taken into account during the design process but not when checking the element. All these checks can be seen and printed in the detailed ultimate limit state check reports (U.L.S.).
    •  Design
      Automatically designs the alignment so all the limitations established by the code and user are met. Following the process, a report on the detailed ultimate limit state checks (U.L.S.) can be obtained. It may occur that the design is not possible, for example, because there is not enough reinforcement provided in the tables. In this case, the geometry and loads should be checked.
  • Configuration menu
    •  Codes
      Users can select the codes to be used for designing the selected frame.
    • Other options in the Configuration menu
      More tools are available in the Configuration menu which allow for other program options to be configured (units, printer, document text styles, drawings, background colour...).

Implemented design codes

Concrete Structures

The concrete codes contemplated by Continuous beams are:

  • ABNT NBR 6118:2007 (Brazil). Norma Brasileira ABNT NBR 6118 (2007). Projeto de estruturas de concreto – Procedimento.
    The program only checks the reinforcement provided by the user for this code. The design of the reinforced concrete sections in accordance with NBR 6118:2007 will be available in upcoming versions.
  • ACI 318M-08 (USA). Building Code Requirements for Structural Concrete.
  • CIRSOC 201-2005 (Argentina). Reglamento Argentino de Estructuras de Hormigón CIRSOC 201 (Julio 2005).
  • EHE-08 (Spain). Instrucción de Hormigón Estructural.
  • Eurocode 2 (EU). Design of concrete structures.
    • EN 1992-1-1:2004/AC 2008. Part1-1. General rules and rules for buildings.
  • Eurocode 2 (France). Calcul des structures en béton.
    • NF EN 1992-1-1 :2005/NA: Mars 2007. Partie 1-1: Règles générales et règles pour les bâtiments.
  • Eurocode 2 (Portugal). Projecto de estruturas de betão.
    • NP EN 1992-1-1:2010/NA. Parte 1-1: Regras gerais e regras para edifícios
  • IS 456: 2000 (India). Indian Standard. Plain and reinforced concrete code of practice (Fourth Revision).
  • NCh 430.Of2008 (Chile). Norma Chilena oficial NCh430.Of2008 (Basada en ACI 318-05).
  • NTC 14-01-2008 (Italy). Norme Tecniche per le Costruzioni.
  • NTE E.060:2009 (Peru). Reglamento Nacional de Edificaciones. Norma E.060 Concreto Armado (2009).

Rolled, welded and cold-formed steel

Continuous beams contemplates the following rolled, welded and cold-formed steel codes.

  • ABNT NBR 8800:2008 (Brazil). Norma Brasileira ABNT NBR 8800 (2008). Projeto e execução de estruturas de aço e de estruturas mistas aço-concreto de edificios - Procedimento.
  • ABNT NBR 14762:2010 (Brazil). Norma Brasileira ABNT NBR 14762 (2010). Dimensionamento de estruturas de aço constituídas por perfis formados a frio – Procedimento.
  • CTE DB SE-A (Spain). Código Técnico de la Edificación. Documento Básico SE-A. Seguridad Estructural. Acero.
  • EAE 2011 (Spain). Instrucción de Acero Estuctural.
  • Eurocode 3 (EU). Design of steel structures.
    • EN 1993-1-1:2005/AC:2009. General rules and rules for buildings.
    • EN 1993-1-2:2005/AC:2009. General - Structural fire design.
    • EN 1993-1-3:2005/AC:2009. General - Cold formed thin gauge members and sheeting.
    • EN 1993-1-5:2005/AC:2009. General - Strength and stability of planar plated structures without transverse loading.
  • Eurocode 3 (Bulgaria). Design of steel structures.
    • BDS EN 1993-1-1/NA:2008. General rules and rules for buildings.
    • BDS EN 1993-1-2/NA:2007. General rules - Structural fire design.
    • BDS EN 1993-1-3:2007. General rules – Supplementary rules for cold-formed members and sheeting.
    • BDS EN 1993-1-5/NA:2008. Plated structural planes.
  • Eurocode 3 (France). Calcul des structures en acier.
    • NF EN 1993-1-1/NA:2007. Règles générales et règles pour les bâtiments.
    • NF EN 1993-1-2/NA:2007. Règles générales - Calcul du comportement au feu.
    • NF EN 1993-1-3/NA:2007. Règles générales - Règles supplémentaires pour les profilés et plaques formés à froid.
    • NF EN 1993-1-5/NA:2007. Plaques planes.
  • Eurocode 3 (Italy). Progettazione delle strutture di acciaio.
    • UNI EN 1993-1-1:2010. Regole generali e regole per gli edifici.
    • UNI EN 1993-1-2:2011. Regole generali - Progettazione strutturale contro l’incendio.
    • UNI EN 1993-1-3:2010. Regole generali - Regole supplementari per l’impiego dei profilati e delle lamiere sottili piegati a freddo.
    • UNI EN 1993-1-5:2009. Elementi strutturali a lastra.
  • Eurocode 3 (Portugal). Projecto de estruturas de aço.
    • NP EN 1993-1-1/NA:2010. Regras gerais e regras para edifícios.
    • NP EN 1993-1-2/NA:2010. Regras generais - Verificação da resistência ao fogo.
    • EN 1993-1-3:2006/AC:2009. General rules – Supplementary rules for cold-formed members and sheeting.
    • EN 1993-1-5:2006/AC:2009. Plated structural elements.
  • Eurocode 3 (United Kingdom). Design of steel structures.
    • BS EN 1993-1-1/NA:2008. General rules and rules for buildings.
    • BS EN 1993-1-2/NA:2009. General rules – Structural fire design.
    • BS EN 1993-1-3/NA:2008. General rules – Supplementary rules for cold-formed members and sheeting.
    • BS EN 1993-1-5/NA:2008. Plated structural elements.
  • IS 800: 2007 (India). Indian Standard. General construction in steel – Code of practice (Third Revision).
  • NTC: 14-01-2008 (Italy). Norme tecniche per le costruzioni.