Week 1 Challenge

ANSWER:

AIM & INTRODUCTION:

1. Aim of the project is to Assess the Dead Loads of Box Girder Bridge located within 60 km radius from Bay of Bengal, calculate the loads and to apply it in Staad Pro and perform Structural Analysis.

2. Width of the bridge Deck Slab is 10.2 m

3. Span of the bridge is 12.00 m

4. Pier size is 2.5 m diameter

5. Seismic Zone is Zone IV

6. Wind Speed is 47 km/hr

7. Unit wt of soil is 19 kn/cu.m

PROCEEDURE:

1. Draw the section of the Box Girder Bridge along with dimensions.

2. Break up from the drawing differenT sizes of Rectangles, Triangles, Segment and Trapezoidal and give numberings and calculate the areas for all the sizes. Calculate total area of Deck Slab and Box Girder.

3. Calculate self wt of Deck Slab, Self wt=Area x Unit wt of concrete

=2.30 x 25 = 57.5 kn/m (Area 2.30 sq.m as per area calculation sheet attached)

4. Calculate self wt of parapet wall (2 nos) Self wt=2 x Ht x thickness x unit wt of concrete

=2 x 1.00 x 0.30 x 25 (Assuming parapet ht 1 m and thickness0.3 m)

=15 kn/m

5. Calculate Self Wt of Box Girder, Self Wt= Total Area of Girder x Unit Wt of concrete.

= 3.17 x 25 (Area of Girder 3.17 m2 as per area calculation sheet attached)

= 79.25 kn/m

6. Calculate Total Dead Load, Total Dead Load= Self Wt of Deck Slab + Self Wt of Parapet + Self Wt of Box Girder

= 57.5 + 15 + 79.25 = 151.75 kn/m

This Dead Load is applied in Superstructure as UDL

STEPS TO GENERATE THE MODEL WITH PROPERTIES AND SUPPORT CONDITIONS, LOAD APPLICATIONS:

1. Open Staad Pro software

2. Click Geometry then go to Nodes.In no 1 node put 0 in all direction x, y and z. In node 2 put 12.00 in z direction as span od the bridge is given 12.00m.

3. Then click Commands and go to support specification, then Fixed and Add. Then select fixed support, click the use cursor to assign to node click the node and click assign. Repeat same proceedure to give support to both the node then click close.

4. Click Command go to member property, then prismatic, go to assign profile in property, put beam in profile specification, put concrete in material and click Add. Select the given property concrete, select the beam use Assign to selected beam and click Assign and close.

5. Next Command go to Loading and primary loads. Give Load Cases Details and in load type and title give Dead Load then Add and close. Select given Dead Load and click Add. Then click Member Load and in Force put in W1 (-)151.75 kn/m, the total Dead load calculated from the given section of Box Girder Bridge. minus sign is given as it was acting from opposite direction of Global Y and select GY, Add and close. Select the total load given, select the beam then Use Assign to selected beams and click Assign.

6. Go to Analyze the Run Analysis.

7. Error occured in the result and could not go to post processing mode. Error given as all degrees of freedom fixed may be due to end support.

8. B.M and SF details coud not be gathered due to error.

9. Report of the Analysis is attached.