CYPECAD

As of previous version, the anchorage length of the columns at the last floor and the splice length at other floors could be reduced. Now, with the 2014.d version, users can reduce the length of only bars that are in tension, in which case, a minimum resultant length for bars in tension has been established as Lb (basic anchorage length). This way, the anchorage lengths and splice lengths (if the reduction is also applied to floors below the last floor) will be more uniform.

To implement this new option, the “Reduction of anchorage lengths in columns” dialogue box now contains a new option: “Only for bars in tension”. This option can be activated separately for the last floor and for floors below the last floor.

In previous versions, users could only introduce one axial stiffness coefficient for all the reinforced concrete columns, shear walls and walls of the job. As of the 2014.d version, three generic axial stiffness coefficients exist which can have different values:

• Axial stiffness coefficient for columns
• Axial stiffness coefficient for shear walls
• Axial stiffness coefficient for walls (reinforced concrete walls and plane stress walls )
  
  

As well as the three generic axial stiffness coefficients, the 2014.d version of CYPECAD also allows for specific axial stiffness coefficients to be assigned to each column, shear wall, reinforced concrete wall or plane stress wall of the job.

An axial stiffness coefficient can be assigned to these elements with a different value at each span, following the process detailed below:

• For columns
  The individual axial stiffness coefficients are assigned to each column (Column Definition tab > Introduction > Columns, shear walls and starts > Axial stiffness coefficient > select a column > select “Column properties which differ from the general properties of the job” > Introduce the axial stiffness coefficients for each floor).
  
• For shear walls
  The axial stiffness coefficients for shear walls are assigned to each shear wall type, which implies that all the shear walls of the same type that are introduced will have the axial stiffness coefficients for that type (Column Definition tab > Introduction > Columns, shear walls and starts > Edit > select a shear wall > Define types > select “With different axial stiffness coefficient” > introduce the axial stiffness coefficients for each floor).
  
• For reinforced concrete walls and plane stress walls
  The axial stiffness coefficients for walls are assigned to each wall span that is introduced in a single introduction step (Beam Definition tab > Beams/Walls > Edit > select a wall span > select “With different axial stiffness coefficient” > introduce the axial stiffness coefficients for each floor).

CYPECAD now allows users to apply reduction coefficients to the concrete resistance for each column span that is selected. This is possible with codes which can use the advanced column editor.

These coefficients are defined using the Concrete resistance option (Column Definition tab > Introduction > Columns, shear walls and starts). A column is selected using the left mouse button, after which a dialogue box appears on-screen where users can:

• If the Job general data option is activated, user can:
  • View the type and general concrete reduction coefficients of the job
• If the option: Reduce the concrete resistance is activated, users can:
  • View the type and general concrete reduction coefficients of the job
  • Introduce concrete resistance reduction coefficients for each column span
  • Modify the concrete resistance reduction coefficient at the required spans

This allows users to define the design resistance of the concrete for each column span if any tests have been carried out indicating the concrete has a low resistance.

Using the “Copy” option of the “Columns, shear walls and starts” dialogue box (Column Definition tab > Introduction > Columns, shear walls and starts), the program allows for the properties of a selected column to be copied to another that has already been introduced. Amongst the properties that can be copied are the reduction coefficients of the column selected as the model column, if the Concrete resistance option is activated in the dialogue box that appears when the column is selected.

A new option has been implemented whereby users can define a different maximum aggregate size for each type of element: floor slabs, foundations, columns or walls (Job ˃ General data ˃ Aggregate properties in the reinforced concrete section).

Additionally, when the concrete EHE-08 (Spain) or ABNT NBR 6118 Projeto Junho 2013 (Brazil) codes are used, the nature of the aggregate can also be defined, with different values for floor slabs, foundations, columns or walls if users indicate it so. These design codes contain a correction coefficient of the longitudinal deformation module of the concrete, which depends on the nature of the aggregate used for its elaboration.

Using the EHE-08 code, the following aggregate nature types can be selected in accordance with that indicated in Table 39.6 (belonging to the comments of article “39.6. Módulo de deformación longitudinal del hormigón”):

• Cuarcita
• Arenisca
• Caliza normal
• Caliza densa
• Ofita basalto y otras rocas volcánicas - Poroso
• Ofita basalto y otras rocas volcánicas - Normal
• Granito y otras rocas plutónicas
• Diabasas
  

In the EHE-08 design code, the correction coefficient of the modulus of elasticity of the concrete is contained within the comments of the code, and so it is not obligatory for users to comply with it. When the nature of the aggregate is quartzite (cuarcita), the correction factor of the elasticity modulus has a value of 1, and this would be the option to be used if the reduction factor is not to be applied or, obviously, if this is the real nature of the aggregate that is used.

Using the ABNT NBR 6118 Projeto Junho 2013 code, the following aggregate natures can be selected as indicated in article “8.2.8. Módulo de elasticidade”:

• Basalto
• Diabásio
• Granito
• Gnaisse
• Calcário
• Arenito
  

Using the ABNT NBR 6118 Projeto Junho 2013 code, when a value of 1 is assigned to the correction coefficient of the modulus of elasticity of the concrete, it belongs to aggregates with “Granito” and “Gnaisse” natures.