Earthquake and Wind Load Calculators
Earthquake Loads
R/C BUILDING has a calculator that will generate earthquake loads following AS 1170.4, based on the geometry and loading that define a model. Earthquake loads are applied in the X and Y directions in separate Basic Load Cases that are defined by the user. Each floor can have one load per Basic Load Case.
R/C Building gives two options in the calculation of earthquake loads: “Static Analysis” and “Dynamic Analysis, 2D”. In the case of “Static Analysis” option, earthquake loads are calculated based on the design response spectrum defined in AS 1170.4 using the fundamental natural period of the structure. R/C Building calculates the fundamental natural period of the structure based on the empirical formula given in AS 1170.4; however it also allows to users to enter the values determined through dynamic analysis.
In the case of “Dynamic Analysis, 2D” option, modal periods of the structure will be calculated by 2D Frequency Analysis. Dynamic analysis of a structure by modal response spectrum method uses the peak response of all modes having a significant contribution to the total structural response. Peak modal responses are calculated using the spectral accelerations of the response spectrum curve that corresponds to the modal periods. A range of response spectrum curves for different soil conditions are available in the software. Maximum modal contributions can be combined with both CQC (Complete Quadratic Combination) and SQSS (Square Root of the Sum of Squares) methods.
Users have also the option to enter their base shear values as a percentage of the total structure seismic weight.
Earthquake loads in each orthogonal direction (X and Y) can automatically be applied at one of the following positions selected by the user:
R/C Building evaluates automatically the mass and shear centroids of each floor.
Wind Loads
R/C BUILDING has a calculator that will generate wind loads following AS 1170.2, based on the geometry and loading that define a model. Wind loads are applied in the positive and negative X and Y directions in separate Basic Load Cases. Cardinal directions (N, S, E, W) must be defined as a Basic Load Case for each direction. Each floor can have one load per Basic Load Case.
Dynamic response factor (Cdyn) must be taken as 1 for structures with natural first mode fundamental frequencies higher than 1 Hz. For tall buildings and towers with natural first mode fundamental frequencies less than 1 Hz but larger than 0.2 Hz, dynamic response factor as well as loads due to along-wind and crosswind responses can also be calculated by the software according to AS 1170.2 Section 6.
Wind loads in each orthogonal direction (X and Y) are automatically applied to the faces of each floor.
With all so many structural building analysis software out there, R/C Building stands out as the one that has the leanest tool sets to master, yet provides the engineers with the powerful and sufficient tools to complete their design job.
Using R/C Building 2009, user can construct a model in a matter of a day or two, saving the valuable time to review the structure and modify the design based on the comprehensive results the software produces.
