RAM FrameRelease 14.02 (January 2010)
Bulent N. Alemdar, Ph.D., P.E.SR Software Product Research Engineer
New Features\Enhancements
• Eccentric Loads on Semirigid Diaphragm (i.e., torsional moments due to accidental eccentricity effects)– Wind, Seismic and Response Spectra Analysis
• P-Delta for Semirigid Diaphragms
• Enhancement for Current P-Delta Implementation (Rigid Diaphragms)– P-Delta effects due to mass loads (default)– Or P-Delta effects due to Dead and Live Loads
2 | WWW.BENTLEY.COM
New Features\Enhancements
• NBC of Canada 2005
– Wind (Section 4.1.7, Division B)
– Seismic (Section 4.1.8.11, Division B)
– Modal Response Spectra Analysis (Section 4.1.8.12, Division B)
3 | WWW.BENTLEY.COM
New Features\Enhancements
• Nodal Moments
• In-core and Out-of-Core Sparse Solver Updated (faster execution time)
4 | WWW.BENTLEY.COM
New Features\Enhancements
• Center of Rigidity Report Updated– Diaphragm Lateral Stiffness Reported
• Loads & Applied Forces Report Updated– Windward and Leeward Pressures Reported for
Semirigid Diaphragms
• Applied Story Forces Dialog– Alternative Ways to Scale Arrows (Log and
Linear Scaling)
5 | WWW.BENTLEY.COM
Eccentric Loads on Semirigid Diaphragm
6 | WWW.BENTLEY.COM
7 | WWW.BENTLEY.COM
Eccentric Wind LoadsUniform wind load profile is converted to a trapezoidal
load profile that generates code specified eccentric effects (i.e., accidental torsion effects)
Uniform Wind Line Load (Y)
Trapezoidal WindLine Load (Y+E)
8 | WWW.BENTLEY.COM
Eccentric Seismic LoadsDistributed seismic nodal loads are modified to reflect
code specified eccentric effects (i.e., accidental torsion effects)
Seismic loads increased
Seismic loads reduced
Deflected shape indicates eccentric loading (Y+E)
9 | WWW.BENTLEY.COM
Response Spectra Analysis
Distributed seismic nodal masses modified to reflect code specified eccentric effects (i.e., accidental torsion effects)
P-Delta for Semirigid Diaphragms
10 | WWW.BENTLEY.COM
P-Delta for Semirigid Diaphragms
• A separate analysis internally run for gravity load cases (dead + live )– Axial forces (also referred to as P-Delta axial force) for
columns inside semirigid diaphragms are stored– These axial forces are utilized to compute element
geometric stiffness matrices for the columns.
• All load cases are run with modified column stiffness (i.e., element geometric stiffness matrices applied to column stiffness)
• This process is automated and transparent to user.
11 | WWW.BENTLEY.COM
Enhancement for Current P-Delta Implementation (Rigid Diaphragms)
12 | WWW.BENTLEY.COM
Enhancement for Current P-Delta Implementation (Rigid Diaphragms)
13 | WWW.BENTLEY.COM
Diaphragm Mass used forCalculating P-Delta Effects (default)
Dead + Live Loads Applied to Diaphragm used for Calculating P-Delta Effects
NBC of Canada 2005
14 | WWW.BENTLEY.COM
NBC of Canada 2005 - Wind
15 | WWW.BENTLEY.COM
NBC of Canada 2005 - Wind
16 | WWW.BENTLEY.COM
NBC of Canada 2005 - Seismic
17 | WWW.BENTLEY.COM
NBC of Canada 2005 - Seismic
18 | WWW.BENTLEY.COM
NBC of Canada 2005 – Modal Response Spectra Analysis
19 | WWW.BENTLEY.COM
NBC of Canada 2005 - Modal Response Spectra Analysis
20 | WWW.BENTLEY.COM
Nodal Moments
21 | WWW.BENTLEY.COM
Nodal Moments
• Nodal Loads Defined in RAM Modeler:
22 | WWW.BENTLEY.COM
Nodal Moments• Nodal Loads Used in RAM Frame
23 | WWW.BENTLEY.COM
24 | WWW.BENTLEY.COM
In-core and Out-of-Core Sparse Solver Updated
New version of In-Core & Out-of-Core Sparse Solver integrated. It provides further reduction in analysis time (performance gain for large models)
25 | WWW.BENTLEY.COM
Center of Rigidity Report
Diaphragm Lateral Stiffness Terms (used for identifying soft\weak story according to code specifications)
26 | WWW.BENTLEY.COM
Applied Story Forces Dialog
• Further Information– The Bentley Structural Team (communities.bentley.com/)
27 | WWW.BENTLEY.COM
• Further Information– RAM Structural System V8i (www.bentley.com\
ramstructuralsystem)
28 | WWW.BENTLEY.COM