# New concrete design in SCIA Engineer 18 according to SIA 262:2013

18.0

Highlights (Design of 1D members according toSIA 262:2013 )
Recalculated internal forces for the design
Capacity and interaction diagram check ULS
Shear and torsion checks for ULS
concrete and reinforcement stress limitation check for SLS
Integrated section check solution with reinforcement templates
Calculation of short and long term deflection

Highlights (Design of 2D members according to SIA 262:2013 )
Calculation of longitudinal reinforcement according to ULS
Simplified workflow to calculate the provided reinforcement according to ULS
Calculation of short and long term deflection

## Supported functionality of the concrete design

### 1. Calculation of internal forces for the design

The internal forces for the design are calculated automatically in this version, nevertheless, the design itself is not supported but still, the user can use these re-calculated internal forces to do some manual design. Moreover, all the supported checks are based on these re-calculated internal forces.

Basically, this re-calculated internal forces is followed some conditions from the code like

a. Reduction of internal forces over the support (shear and bending): this condition will be useful in case of economical design. The user has this option available inside the concrete setting and s/he can switch that off.

b. Modification of the internal forces: for the check purpose, the designer can modify the internal forces in a very practical way. Simply, s/he can set the modification to ignore some small value of the internal forces, To read more, please click here

c. Modification of the internal forces due to the first and second order effect according to 4.3.7.5 and 4.3.7.7 from the SIA 262:2013 code

### 2. ULS checks According to SIA262:2013

Several checks have been implemented like:

a. Capacity and interaction checks: In this check, the user can see the interaction diagram check which can be simply modified by the concrete setting and the stress-strain check for concrete. To perform this check, the user needs to add a practical reinforcement inside the cross-section by using the reinforcement input command.

The results of this check are divided into three groups (Overall check, stress-strain check, and interaction diagram check). The output of this check can be presented graphically or numerically as brief, standard and detailed output).

b. Check Shear+Torsion (ULS): this is a very useful command to check the interaction between shear and torsion on 1D members. The results of this check are divided into three groups (overall interaction, shear, and torsion). The user can call some useful results like (the recalculated internal forces and the resistance of the cross-section regarding the shear, torsion, and shear-torsion). All the results can be seen graphically and numerically and brief, standard and detailed output.

### 3. SLS checks According to SIA262:2013

a. Stress Limitations (SLS): Stress limitation (SLS) check is based on the calculation of stresses in particular component (concrete fiber, reinforcement bar) and comparison with limited values with respect of SIA262:2013 requirements. Based on the internal forces, concrete cross-section and reinforcement defined by the user, SCIA Engineer is able to calculate the plain of equilibrium of a member or a single cross-section and find the actual value of stresses in each component.

In this check, the verification of cracks section is done in according to 4.4.1.3 from SIA262:2013 code. According to table 17 in the code, the stress can be checked in three different stages:

Normal requirements: are sufficient if cracks are tolerated and no particular demands exist with respect to impermeability and appearance;

Increased requirements: apply if special demands exist in terms of functionality and appearance and a good crack distribution is desired;

High requirements: apply if a crack width limitation is desired for quasi-permanent and frequent load cases.

The user can choose the requirement that fit his case from the global concrete settings.

Generally, four checks can be done:

1) Stress limitation due to brittle failure - prevention of Brittle failure check always but only in case fctd is reached

2) Stress limitation due to Limit crack width for restrained deformation.

3) Stress limitation due to crack width for QP load – just for high requirements only (not for normal and increased requirements)

4) Stress limitation due to crack width for freq load – just for increased and high requirements only (not for normal requirements)

In addition, the results can be different depends on constrained or restrained deformation.

The results of this check are merged in one group, however, the user can select/see different results graphically or numerically supported by brief, standard and detailed output (σs; σ fsd; σs,qp; σs,freq; σs,qp,adm; σs,freq,adm

### 4. Check Detailing provisions: the following detailing provision for 1D members are supported in SCIA Engineer version 18:

#### A ) detailing provision for beams and ribs

5.2.3.2 - min bar distance

5.2.4.1 - min mandrel of diameter for stirrups

5.5.2.2 - maximal spacing of stirrups; minimal reinforcement percentage of stirrups

#### B) detailing provision for columns

5.2.3.2 - min bar distance

5.5.4.1 - minimal dimensions of compressed members

5.5.4.2 - minimum longitudinal reinforcement area; minimum bar diameter

5.5.4.5 - max. ratio of long reinforcement

5.5.4.7 - maximal spacing of stirrups

5.5.4.8 - in polygonal shape columns must be at least one bar in each corner

### 5. Section check:

The Section Check is a part of the concrete design module of SCIA Engineer and simplifies both design and checking of sections on 1D concrete members. It provides a clear overview of code checks in a section according to SIA262:2013.

The main features include a definition of reinforcement bars, verification according to standards and generation of reports.

The main benefit for the user is the ability to perform directly from the 3D model a fast checking of a single concrete section of a particular 1D member, which means that there is no need to export internal forces and geometry to an external tool. The user simply selects a section on the member, quickly defines and/or edits the reinforcement and the results of the checks are immediately shown for the most critical ULS or SLS combination. Everything is fully integrated into the 3D model in a friendly GUI environment.

Section Check nicely fits in a daily workflow of structural engineers:

• No need for external standalone applications: both design and checks of a concrete section are fully integrated into the 3D model.

• Effective and easy use: predefined templates are included, results are clear and immediately available on the screen, all the assumptions applied in calculations are displayed.

• The design and assessment fully comply with the SIA262:2013 code.

• Support of all concrete sections from SCIA Engineer cross-section library.

• The calculation report can be inserted in the Engineering Report

• The detailed presentation of results as well as the summary of performed checks are always available on the screen.

### 6. Design of 2D members (plates, walls, and shells)

a. Calculation of internal forces: first of all, the procedure for re-calculate the internal forces for this code is quite similar to the procedure from the Eurocode with respect to Baumann's transformation method. Moreover, the influence of additional tensile force coming from shear is taken into account as well.

b. Design of longitudinal reinforcement:

c. Design of longitudinal reinforcement: The user can design the longitudinal reinforcement according to SIA262:2013 code. s/he can see the results in two directions/surface.

The results of 2D design are divided into different groups.

First one is the statical required reinforcement As, req,stat. These results are representing the needs for tension reinforcements without any detailing requirement from SIA262:2013 code. The idea of presenting this results is to help the designer compare the results from SCIA Engineer with hand calculation.

The second group is required longitudinal reinforcement + detailing provision As, req: As it is clear, the difference with this type of results will be the detailing provision.

The third group is the provided reinforcement As,prov. The aim of presenting this type is to help the concrete designer reorganize the final design by more practical results and send this result to the draftsman. In reality, the concrete designer will not but reinforcement differently in each FEM, so s/he will try to arrange the final reinforcement in a way to make it easy to understand by the draftsman and the labor at the site. Therefore, to save the time for the user, SCIA Engineer has implemented a nice method to define the basic amount of reinforcement which it should be a constant amount over the slab, project and give some condition for SCIA Engineer to design the final reinforcement if the basic one is not enough. To read more about this methodology, please click here.

All the results can be shown graphically or numerically supported by brief, standard and detailed output.

### 7. Code dependent deflections (CDD)

Long-term deflections, especially in cracked and slender R/C flexural members, may cause delayed damage in non-structural elements, so they must be accurately estimated at the design stage.

The CDD calculation has been designed exclusively for concrete beams and plates, as it is based on the wording of technical standards for design and checking of concrete structures. The aim is to calculate the long-term deflections according to the rules described in the national code.

A big improvement has been added to give the designer very fast and sophisticated tool to calculate the long-term deflection in according with Eurocode and the national annexes.