Cable Elements with Large Displacement Options
SAP2000 has a nonlinear catenary cable element for large displacement analysis. Nonlinear time history dynamic analysis of large displacements enables engineers to capture inertial effects along with the complex changes in behavior as member forces change from tension to compression and vice versa during various stages of the analysis. Cable lifting and launch, analysis of cable stayed structures, and mooring analysis are among the applications where catenary action often occurs. The SAP2000 cable element utilizes a convenient shape finder where the user can specify max vertical sag, relative length, end tension and other parameters and the shape finder interactively computes the geometry of the cable object with graphical display.
Offshore and Transportation Acceleration Loads
SAP2000's sea state load pattern enables users to apply rotational and translational acceleration loads as Rotations/Translations or Accelerations/Velocities with phase angle and a specified point of rotation that can be offset from the model.
Offshore Related Features
SAP2000 offers API RP-2A and Norsok N-004 offshore design codes, which include checks for joint-can punching shear among other design features. In addition, API 4F, AISC (with robust implementation of Direct Analysis method), Eurocode, Australia/New Zealand, and numerous other steel and concrete design codes are included. Built-in wave loading per Airy, Stokes 5th-order, and cnoidal wave theories can be applied as multi-step static loading to simulate the wave moving through the structure, or applied as linear or nonlinear time history loading in order to include inertial effects. Water currents can simultaneously load the portions of the structure below the water line with corrections for user specified marine growth as a function of depth, drag and inertia effects, and buoyancy.
Users can view resultant wave velocities and accelerations graphically with color coded plots or produce output tables of the values that can be exported to Excel.
SAP2000 rigorously analyzes geometric nonlinear effects of P-Δ and P-δ local deformations. In addition to small displacement P-Delta, SAP2000 is also able to analyze P-Delta with large displacements under static and time history loading.
SAP2000 Modal and Eigen buckling analysis cases can be based on the stiffness and boundary conditions from one or more static nonlinear P-Delta cases in which the structure is already in a deformed and stressed state. P-Delta and other nonlinear effects may change the Modal fundamental period and Eigen buckling behavior. This can be particularly important in analysis of mast drilling structures, as well as in analysis of other structures that support heavy gravity loads relative to lateral stiffness which are common in process, power, and offshore industries.
Wind Load on Open Frame Structures
SAP2000 offers auto-generation of wind loads on open frame structures per ASCE 7, API 4F, and API RP2A which accounts for section dimensions and local axis of exposed frames/beams, saving the user from manually calculating and assigning these loads. Rigid diaphragms are not required. Furthermore, when fireproofing or ice thickness is assigned using SAP2000's fireproof load feature, the wind load is automatically adjusted to account for it. These auto-wind load capabilities can be a tremendous time saver.
SAP2000 can automatically generate static and response spectrum seismic loads per IBC/ASCE, NBCC Canadian, and other international standards including automatic application of accidental eccentricity with either rigid diaphragm or flexible semi-rigid diaphragms. ASCE 7-10 Clause 12.3.1 describes conditions where the stiffness/flexibility of diaphragms should be considered, and many structures in process, power, and offshore industries fall under this flexible diaphragm category.
For IBC seismic load generation, Ss and S1 values for IBC auto-seismic load can be auto-searched by zip code or specified latitude/longitude. SAP2000 can also analyze seismic cases using linear or nonlinear time history dynamic analysis .
SAP2000 Section Designer (SD) comes integrated with every SAP2000 license, and calculates cross sectional properties and moment curvatures of irregular and built-up sections modeled as a frame/beam element. SAP2000 can design steel and concrete SD sections, and can work with mixed materials as a composite section. After defining a concrete column, including octagonal and hex columns common in process plants, SD displays a P-M-M diagram for standalone column design in addition to section properties and moment curvature.
Users can visualize details of complex built-up section geometries using the rendered extruded view option. Geometry can be created within SD’s user interface or by importing from DXF.
Advanced Dynamic Analysis
SAP2000 offers modal, Ritz vector, response spectrum, steady state harmonic, power spectral density, and time history dynamic analysis options. Time history dynamic analysis can account for nonlinear boundary conditions such as compression-only springs, gaps, friction, or multi-linear plastic P-Y/T-Z soil behavior. In addition, SAP2000 nonlinear time history analysis can account for P-Delta large displacements as well as material nonlinear behavior in frame/beam and shell elements. Time history loading can apply to joint loads, distributed loads, imposed displacements, thermal loads, accelerations, wave load, wind load, and strain loading.
Steady state harmonic analysis can account for frequency dependent springs (K) and dashpots (C), which are often needed when analyzing soil boundary conditions for foundations which support vibrating machinery. In addition, steady state analysis can analyze an entire “sweep” of different frequencies or machine speeds all in one run.
Multiple Mass Models
SAP2000 enables users to define and utilize multiple mass models in the same analysis. This capability is often used to analyze static seismic and dynamic cases simulating the mass model for the full of liquid contents scenario, and again for the empty scenario in order to consider different ‘seismic weights’ per ASCE and other standards. Multiple mass models can also be useful for offshore structural design and construction engineering analysis where mass distribution can change significantly at different stages over time. With this capability, users no longer need to create multiple separate models and instead can post-process the results of multiple scenarios in a single model.
Automatic Fireproof Loading
SAP2000 offers auto-load generation of fireproofing weight with spray-on and encased in concrete box fireproof options to selected members. This feature eliminates the need to manually calculate and assign fireproofing load and mass, a time consuming task prone to user error. When fireproof load is assigned using this feature, SAP2000 automatically adjusts auto-wind load generation to account for the added area.
Center of Gravity
SAP2000 can automatically determine the center of gravity (CG) of the structure based on self-weight and user selected assigned loads.
If piping, cladding, equipment or other gravity loads are applied as assigned loads, users have the option to include those assigned loads in the CG calculation and report.
Step-by-Step Stage Construction Analysis
SAP2000’s stage construction analysis enables users to analyze different construction/erection scenarios with the ability to add or delete elements, loads, and/or supports at each stage, with additional options to modify releases and section properties at every stage. This capability can be fully nonlinear in order to consider geometric and material nonlinear behavior, as well as nonlinear boundary conditions and time dependent effects of creep and shrinkage. Time history, modal, and buckling analysis cases can be based on the stressed state of any stage of a staged construction analysis. Although stage construction is often used for applications such as segmental construction, incremental launching, and progressive collapse, consideration of stage construction analysis can offer more realistic calculation of reactions and stresses for many other day-to-day structural design applications.
Intermediate internal joints can be automatically added along frame/beam and finite element objects for dynamic or nonlinear analysis without having to manually divide the object. If framing connectivity changes, internal joints are automatically adjusted for analysis while keeping track of physical object lengths. If an area finite element object mesh changes, joints along the adjacent perimeter frame/beam objects are added or modified automatically for connectivity without dividing object physical lengths.
Import SACS and Other Analysis Models
Input files from SACS®, StruCAD*3D and STAAD® models can be imported directly into SAP2000. These model imports are comprehensive and include geometry, section properties, local axes, supports, releases, load assignments, and load combinations.