Although reinforced concrete is at least as frequently used for plate structures as it is for frameworks, standards and technical literature provide comparatively little information on the design of two-dimensional structural components. In particular, the design of shell structures that are simultaneously subjected to moments and axial forces is rarely described in reference books. Since the finite element method allows for a realistic modeling of plate structures, design assumptions and algorithms must be found to close this "regulatory gap" between member-oriented regulations and computer-generated internal forces of plate structures.
Dlubal Software GmbH meets this challenge with the add-on module RF-CONCRETE Surfaces. A consistent design algorithm for dimensioning reinforcement directions consisting of two and three layers has been developed based on the compatibility conditions defined by Baumann in 1972. However, the module is more than just a tool for determining the statically required reinforcement: It also includes regulations concerning the allowable maximum and minimum reinforcement ratios for the different types of structural components (2D plates, 3D shells, walls, deep beams) like they are given as design specifications in the standards.
When determining reinforcing steel, RF-CONCRETE Surfaces checks if the concrete's plate thickness, which stiffens the reinforcement mesh, is sufficient to meet all requirements arising from bending and shear loading.
In addition to the ultimate limit state design, the serviceability limit state design is also possible in the module. These designs include the limitation of the concrete compressive and the reinforcing steel stresses, the minimum reinforcement for crack control, as well as crack control by limiting rebar diameter and rebar spacing. For this purpose, analytical and nonlinear design check methods are available for selection.
If you also have a license for RF-CONCRETE Deflect, you can calculate the deformations with the influence of creep, shrinkage, and tension stiffening according to the analytical method.
With a license of RF-CONCRETE NL, you can consider the influence of creep and shrinkage when determining deformations, crack widths, and stresses according to the nonlinear method.
The design is possible according to the following standards:
- EN 1992-1-1:2004/A1:2014
- ACI 318-19
- CSA A23.3-19
- SIA 262:2017
- GB 50010-2010
The figure on the left shows the National Annexes to EN 1992-1-1 that are currently implemented in RF-CONCRETE Surfaces.
All intermediate results for the design are comprehensively documented. In line with the philosophy of Dlubal Software, this provides a notable transparency and traceability of design results.
We hope you will enjoy working with RF-CONCRETE Surfaces.
Your Dlubal team