Finite Element Software Report based on the dynamic explicit analysis performed on a truss bridge, using Abaqus

Learning Outcomes of the Assessment

LO2: Evaluate different material models and element types to approximate the behaviour of

different materials and structures.

LO4: Apply commercial Finite Element Analysis software for linear and nonlinear analysis of

structures.

LO5: Critically apply elastoplastic constitutive models.

Assessment guidelines

Produce a 2000-word +/- 10% (excluding references and appendices) Finite Element Software

Report based on the dynamic explicit analysis performed on the truss bridge below, using

Abaqus/Explicit. The truss in the figure below is a 2D structure, which is dynamically loaded with

the concentrated forces shown during a 1 second loading step time, and 10 seconds total duration

with 9 increments. The selection of all material parameters, such as Young’s Modulus, Poisson’s

ratio, loading steps and types, applied boundary conditions etc., has been performed. The structural

material for the truss system is AISI 1005 (UNSG10050) carbon steel, Young’s Modulus of

200E+9, Poisson’s Ratio of 0.3, Density of 7872kg/m3, Specified minimum yield strength of

280MPa, Ultimate tensile strength of 310 MPa and a cross-sectional thickness of 3.14E-4 m. The

span of the truss is 60 m and a height of 10 m. Each section is reinforced as indicated, below.

Your report should be structured in line with the assessment need as follows.

(1) An introduction and essential background to the Dynamic Explicit analysis and the key

structural characteristics of the given truss bridge, and a clear definition of the objectives of

the assignment.

(2) Based on the course material for week 7, produce a clear outline and description of the

procedure you would have followed to create and model the above structure in Abaqus.

(3) Provide a detailed deductive report based on the resulting assembly of the truss structure

created on the Abaqus software with the concentrated loads, nodes and edges provided below

(Figures 1,2, 3, 4, 5, 6, 7, and 8). Support your position with relevant literature. The units of

the measured variables are as followed: Stress (Pa), Deformation (m), Force (N)

Figure 1. Forces

Figure 2. Vertical Reaction Forces

NN N

N N

Figure 3. Horizontal Reaction Forces

Figure 4. Deformation – Resultant (Cross-sectional thickness: 3.14E-4)

Figure 5. Principal Stresses in S11 Direction (Cross-sectional thickness: 3.14E-4)

The edges around the highest deformation area (2,3 and 13) are plotted below. If the acceptable

maximum strain is 40%, what is your judgement of the selected material?

Figure 6. Deformation – Resultant (Edge 2)

N N

Figure 7. Deformation – Resultant (Edge 3)

Figure 8. Deformation – Resultant (Edge 13)

(4) Based on the stress information provided in this brief and the results so far, justify and

explain why the material selected for the construction for the truss is fit for purpose or not.

The adopted safety factor for the design is 0.75.

(5) Explain the difference between the plots for edges 1_9, and edges 10_14. Is the structure

stable under the condition of edges 1_9, and edges 10_14? Provide detailed explanation and

supported with relevant literature.

Figure 9.Combined Deformation – Resultant (Edges 1-9 and 10-14)

(6) Based on the contour map in Figure 5, extract relevant results of stress and deformation from

any 5 nodes and 5 edges in a tabular form.

(7) If the cross-sectional area of the truss material is increased to 5.0E-3, what difference will it

make in the design life of the truss bridge when compared with the original design cross-

sectional thickness of 3.14E-4 above. Outside stress and deformation, equally consider cost

of the material in your analysis.

Figure 10. Deformation – Resultant (Cross-sectional thickness: 5.0E-3)

Figure 11. Principal Stresses in S11 Direction (Cross-sectional thickness: 5.0E-3)

(8) Provide critical discussion and interpretation of the results, and comments regarding whether

the structure is strong enough to withstand the applied loads.

(9) Design/structural improvements that could be made so that the bridge can withstand greater

loads of longer duration.

Your assignment should be structured as follows

Section/Aspect Content to cover Marks

available

Introduction

1. Provision an essential background to the Dynamic

Explicit analysis and the key structural characteristics

of the given truss bridge. Clear definition of the

objectives of the assignment.

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Main Body:

Discussion and

Critical Analysis

2. Based on the course material for week 7, produce a

clear outline and description of the procedure followed

to create and model the above structure in Abaqus.

3. Provide a detailed deductive report based on the

resulting assembly of the truss structure created on the

Abaqus software with the concentrated loads, nodes

and edges provided below (Figures 1,2, 3, 4, 5, 6, 7,

and 8). Support your position with relevant literature.

4. Based on the stress information provided in this brief

and the results so far, justify and explain why the

material selected for the construction for the truss is fit

for purpose or not. The adopted safety factor for the

design is 0.75.

5. Explain the difference between the plots for edges 1_9,

and edges 10_14. Is the structure stable under the

condition of edges 1_9, and edges 10_14? Provide

detailed explanation and supported with relevant

literature.

6. Based on the contour map in Figure 5, extract relevant

results of stress and deformation from the any 5 nodes

and 5 edges in a tabular form. Justify your choice.

7. If the cross-sectional area of the truss material is

increased to 5.0E-3, what difference will it make in the

design life of the truss bridge when compared with the

original design cross-sectional thickness of 3.14E-4

above. Outside stress and deformation, equally

consider cost of the material in your analysis.

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8. Provide critical discussion and interpretation of the

results, and comments regarding whether the structure

is strong enough to withstand the applied loads.

9. Design/structural improvements that could be made so

that the bridge can withstand greater loads of longer

duration.

Conclusion

Effective summary of the critical points addressed in the assignment, and the most important findings of the discussion. You recommendation should be action- driven, with emphasis on cost and design life implications.

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Layout and

Referencing (list of references can take as

many pages as

necessary/not included in the 2000-

word count)

A high-quality presentation that conforms to principles of academic writing and contains minimal errors in sentence construction, grammar, and punctuation.

The assignment should follow appropriate academic conventions regarding in-text citations and references using the Harvard referencing system.

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Total: 2000 words 100