Advanced Settings of the Building Modeller

In the Advanced Settings dialog box, accessed by the corresponding button, the following information can be defined:

  • Analysis Type: The type of analysis, for which the model will be created, is selected. All nine SeismoStruct Analysis Types are supported. The definition of the control node is made within this module. Users may select directly the floor of the control node, or alternatively choose the automatic definition, in which the control node is defined at the centre of mass of the upper floor or at the floor lower to that (in the case of having a top floor mass less than 10% of the lower floor’s).
  • Frame Elements Modelling: The element class to be used to model the structural members is defined herein. Different frame element types may be employed for columns/beams and walls. Further, it is possible to assign the inelastic displacement-based frame element type (infrmDB) to short members, a choice that improves both the accuracy and the stability of the analysis. Users can determine the maximum length of the short members, below which the infrmDB element type is employed (1.0m by default). Users can also determine the maximum length of the members, below which the elfrm element type is employed (0.4m by default). The inelastic plastic hinge force-based frame element (infrmFBPH) is selected for columns/beams and walls, a scheme that should work well for most practical applications. The maximum frame element length for the discretization of Strip Footings is defined in this tab (1.0m by default). The choice whether to include or not rigid ends in the beams, columns and walls modelling is also done herein. It is noted that these rigid ends are included in the model, when the length of a member’s rigid end is larger than the specified value. The last option of not accepting beams shorter than a specific length is used to avoid the creation of very short beams, due to graphical reasons, by mistake (e.g. by extending slightly a beam’s edge after the column at its end).
  • Slabs Modelling: The option whether to include the effective slab width in the beams modelling is determined.
  • Structural Configuration: In the Structural Configuration tab the number of storeys and their heights are defined; a number from 1 to 100 storeys, with different heights at each storey and the possibility of applying a common height to a range of storeys, may be selected. Up to three underground floors (basement storeys) and their heights may also be defined. The default selection for this module is 3 storeys with 3.00m height each without basement storeys.
  • Loading Combination Coefficients: The loading combination coefficients for the Seismic Combination (e.g. G+0.3*Q±E) of the slabs’ Gravity Live loads and snow (in the case of ASCE 41-23 and TBDY) are defined here. The loading of the slabs is defined for each slab separately in the Slab Properties window.
  • Performance Criteria: Users are able to select which types of performance criteria to include in their analysis. By default strain based criteria for concrete and steel are selected.
  • Code-based Checks: Users are able to select which types of capacity checks to include in their analysis. By default the chord rotation and shear capacities criteria are selected.
  • Soil-Foundation Interaction Link Modelling: When the Consider Uplifting for Inelastic Links check-box is selected, the foundation link element has zero stiffness during the uplift of the footing.

Notes

  1. Even when no rigid ends are defined by the user, offsets may automatically be introduced to ensure adequate alignment of all structural elements.
  2. The slab modelling is carried out with rigid diaphragms; hence, a rigid slab is implicitly considered in the structural configuration, which is the case of the vast majority of R/C buildings. The slab's loads (self weight, additional gravity and live loads) are applied directly to the beams that support the slab.