Challenge

Week 2 Challenge

SSanat Das28 Oct 2023

Question 1.1 How will you assign Circular section to column?

Ans Take a beam as column

Go to Property

Click Define

Select Circle

Input dia

Add>Close

Select column > assign to selected beam

Circular section will be assigned to column

Question 1.2. How will you assign Unit system to a .std model file?

While creating new file, Select Units, Click settings, Click display option, Select Structural units. assign unit system of your choice.

Go to view, Click display option, Select Structural units. assign unit system of your choice.

Go to Geometry, Click Input units, select units of your choice

Question 1.3. What are the parameters to be specified while using “Bay Frame” option?

Ans

Go to geometry tab in that select structural wizard in that select frame model in that select bay frame

Give the parameters like length, height, width, No. of bays along length, No. of bays along height and No. of bays along width

Question 1.4 Name few codal standards incorporated in STAAD Pro software.

Ans-

Euro code, ACI, IS code

Question 1.5 How will you specify the design compressive strength for a RCC section?

Ans-

After applying load and analysing on structure, in analytical modelling Click design select materials as concrete and select the code and then go to define parameters and select FC then specify the

value > Add > Close

Assign to selected element/beam

Question 2. 1. State the “Input” steps involved in RCC design.

Ans-

Following steps are involved in RCC design-

Geometry

Properties

Materials

Specification

Support

Loading and Load combinations

Analysis

Design>Concrete

Select Code

Select parameters>Add>Close

Define parameters>Add>Close

Select Command

Assign to RCC members

Question 2.2 Explain the difference between Fixed and Enforced support condition in STAADPro.

Ans-

When the FIXED or FIXED BUT type of support is specified, for those degrees of freedom which are to be treated as fully restrained, STAAD assumes the displacements to be known quantities whose value is zero. Hence, those degrees of freedom are not considered for the stiffness matrix, and their value is not calculated. (For the FIXED BUT support type, if any degrees of freedom are assigned a spring using the KFX thru KMZ terms, those are treated as unknowns and their displacements are calculated).

When the ENFORCED or ENFORCED BUT type of support is specified, for those degrees of freedom which are to be treated as restrained, STAAD assigns a spring with a very high spring stiffness - translational stiff springs for translational restraints, and rotational stiff springs for rotational restraints. Those degrees of freedom which are free to displace are assigned springs of zero stiffness. Hence, for all the 6 degrees of freedom at such supports, the displacements are calculated. The ones which have a stiff spring will end up having a negligible displacement, and those with zero-stiffness-springs will have a displacement based on the structure geometry, properties and loading.

The following are some of the ramifications of using the two support types.

1) Even though the two types follow different approaches, the end result - joint displacements, member forces and support reactions - should be the same.

2) Since the number of unknowns is less in the former method compared to the latter, the time required to compute the results will also be comparatively less using the first method. If the model is large, there may be a significant reduction in time required to perform the analysis.

3) For supports directly attached to plates or solids, if the supports are subjected to artificial displacements (called sinking support or support settlements), the effects caused by such displacements can be computed only if the ENFORCED type of support is used. In STAAD, support displacement loads cannot be applied to such models when the FIXED type of support is specified.

4) For the ENFORCED BUT type, there is no provision to specify a spring constant. The only choices, which are built into the program, are - zero stiffness or very high stiffness. So, if a user plans to assign his/her own spring constant, the FIXED BUT type is the only choice.

5) If the engineer plans to analyze a model in which support conditions change depending on the loading condition (hence he/she specifies the support command multiple times in the model), there are a few restrictions on how the supports must be assigned. These are mentioned in Section Technical Reference of STAAD Commands > TR.38 Change Specification of the STAAD.Pro Help where the CHANGE command is described. The ENFORCED support may offer a way to overcome some of those restrictions.

Question 3.1 Explain the steps involved in analysis of a model using STAAD Pro sequentially.

Ans -

Read or study drawings (Plan/Elevation/Section)

Input Geometry

Input Properties

Input Materials

Input Specifications/Constants/Supports

Input Loadings and combinations

Run analysis

Specify analysis type

Input design Code Parameters standards

Design

Represent design as document and drawing

Question 3.2 Explain the two ways in which a structural framework/model can be created in STAAD Pro software.

Ans -

Node by node method

Grid method

Structural wizard method

Question 3.3 Elaborate the different support conditions in STAAD Pro.

Ans -

Fixed support

Pinned support

Fixed but support

Enforced support

Enforced but support

Multilinear spring support

Foundation support

Inclined support

Tension/Compression Only Springs support

Question 3.4 How will you extract the stress distribution for a staircase slab?

Ans -

Create the staircase by using the nodes in the geometry panel

After creating the nodes assign the plate elements as the slab property after that define load cases and calculate the area load

acting on the staircase and apply load cases and load combination to the staircase slab and then create a mesh on the plate

element

After that run the analysis and go to post processing mode and click on plate result option in that select stress distribution

result and choose the stress type accordingly and that stress distribution result is displayed

Maximum and minimum stress values are displaced

Question :- 3. 5. Explain the different ways to view SFD & BMD in STAAD Pro.

Ans :-

After completing the design and running the analysis software will provide the BMD and SFD

After the analysis click on Post processing mode and click OK

Go to deflection command and click on beam result

In reaction command click the beam deflection

SFD

BMD

Practical
1. Analyze the following structural elements and validate the results
A. Simply Supported Beam
a. A Simply supported beam with two point loads symmetrically placed
b. Span L = 20m
c. Load P = 50kN each
d. Both P located at 5m from each support

Ans -

> Geomerty tab select add beam and draw the beam by using beam cursor