Week 6 Challenge

Aim: 

To Calculate the Pipe loads for the bridge shown in the figure and to analyse it in Stadd Pro.

Given:

The bridge is located on the banks of the river Narmada

Diameter of pipes = 700mm and 200mm 

Class of pipe = NB Ductile Iron 

The Length of the bridge = 24m

The width of the bridge = 3m

Procedure: 

Step1: To know the load of the DI K9 700 and 200 mm pipes,

From CEEPHO Manual, the self-weight of these pipes can be determined,

                                                                            Figure 1 

Note: DN represents Ductile Iron.

The weight is in Kg, to convert this weight to mass., 

1 Kilos = 0.0098 Kilonewtons (mass)

DI K9 700 mm - 11.0129 kN

DI K9 200 mm - 1.9613 kN

Design and Analysis:

Step 1: Open Stadd Pro connect edition software -> create a new file with the units set to metric standards.

Step 2: Select structure wizard and click howe bridge and enter the following details as per the given details,

Length = 24m, Width = 3m, Height = 3m, Bays along length = 8. Import the model to the Stadd Pro. modelling workflow.

Step3: Delete the diagonal members and connect them accordingly as per shown in the given. See the below figures 2 and 3 for clarifications.,

                                                                            Figure 2

                                                                             Figure 3

Figure 2 represents the actual model as per the given and figure 3 represents the howe bridge imported into Stadd Pro.  from Structure Wizard. 

Step4: Select the first cross beam and right-click to insert node -> Insert node at the centre which is 1.5m -> translational repeat this centre node with 3m spacing to the other 7 cross beams along +X direction. Refer to figure 4 - the red highlighted node at the centre of the cross beams.,

                                                                             Figure 4

Step4: Connect the centre nodes from exterior bottom-end nodes forming diagonal members using add beam command from the geometry tab, Refer to figure 5.,

                                                                             Figure 5

Step5: Select the main left bottom beam from all the bays and translational repeat it along -Z direction for two steps with varying spacings of 1m and 1.64m. These beams signify the path where the pipes will travel. Refer to figure 6., 

                                                                             Figure 6

Step6: Similarly select the main right top beam from all the bays and translational repeat it along -Z direction for two steps with spacings of 1m as per the given diagram., 

Step7: Select the end four nodes and translational repeat them along -Y direction for 6m for 1 step. Join these nodes using add beam command thus creating four piers which support the entire bridge. Refer to figure 7.,

                                                                             Figure 7

Step8: Specification tab -> Select fixed and create foundation -> Assign this fixed foundation to the 8 nodes under the pier.

Step 9: Pier - In the Properties tab -> select define -> Rectangle -> 0.6m x 0.6m -> Assign -> close.

Step 10: In the Properties tab -> select define -> Taper -> F1 = 0.4m, F2 = 0.012m, F3 = 0.4m, F4 = 0.2m, F5 = 0.016m, F6 = 0.2m, F7 = 0.016m. -> Assign -> close. Refer to figure 8.,

                                                                             Figure 8

Step 11: In the Properties tab -> select section database -> India -> ISMB250 -> Assign -> close. Refer to figure 9.,

                                                                             Figure 9

Step 12: In the Properties tab -> select section database -> India -> ISA 65X65X6 -> Assign -> close. Refer to figure 10.,

                                                                             Figure 10

Step 13: In the Properties tab -> select section database -> India -> ISA 90X90X8 -> Assign -> close. Refer to figure 11.,

                                                                             Figure 11

Step 14: In the Properties tab -> select section database -> India -> ISA 50X50X6 -> Assign -> close. Refer to figure 12.,

                                                                             Figure 12

Step 15: In the Properties tab -> select section database -> India -> ISMC 200 -> Assign -> close. Refer to figure 13.,

                                                                             Figure 13

Step 16: In the Properties tab -> select section database -> India -> ISMC 100 -> Assign -> close. Refer to figure 14.,

                                                                             Figure 14

Step 17: In the loading tab -> Load case details -> Generate a load type by clicking add -> primary -> enter CLASS K9 700 DI PIPE and click add.

Step 18: In the loading tab -> Load case details -> Generate a load type by clicking add -> primary -> enter CLASS K9 200 DI PIPE and click add.

Step 19: In the loading tab -> Load case details -> Generate a load type by clicking add -> primary -> enter SELF WEIGHT and click add.

Step 20: In the loading tab -> Load case details -> Select CLASS K9 700 DI PIPE and click add -> In Member load under Uniform forces -> enter the load as -11.0129 kN/m² in the Global Y direction and click add -> Assign this load to the highlighted blue region loaded beams in Figure 15.

                                                                             Figure 15

Step 21: In the loading tab -> Load case details -> Select CLASS K9 200 DI PIPE and click add -> In Member load under Uniform forces -> enter the load as -1.9613 kN/m² in the Global Y direction and click add -> Assign this load to the highlighted blue region loaded beams in Figure 16.

                                                                             Figure 16

Results: 

Click analysis -> Add define commands and run analysis., 

The results can be obtained after analysis of the model and can be viewed in the post-processing tab under the workflow section.,

The deflection of the Model can be seen below in Figure 17 and the critical displacement is highlighted below., Critical Displacement = 25.652 mm.

                                                                             Figure 17

 The Reaction of the foundations can be seen below in Figure 18.,

                                                                             Figure 18

Bending Moment in Z direction -  Critical Bending Moment = 71.714 kN/m. Refer to Figure 19.

                                                                             Figure 19

Bending Moment in Y direction - Critical Bending Moment = 11.428 kN/m. Refer to Figure 20.

                                                                             Figure 20

Shear in Z direction - Critical Shear Force = 14.131 kN. Refer to Figure 21.

                                                                             Figure 21

Shear in Y direction - Critical Shear Force = 20.915 kN. Refer to Figure 22.

                                                                             Figure 22