9:46 1 < Back SEN729 2022 Assessment Task 2 -... Submission Requirement: Individual work: This design project is an individual-based assessment. Submission: You are required to prepare and upload a single PDF file (only one file per submission with your Student ID as the file name) to Assessment 2 submission folder on the unit site (CloudDeakin). The submitted file must be readable by Turnitin. Any other files (Excel, Word, AutoCAD, CIVIL 3D, etc.) will not be marked or referenced. . Extension Requests: Please follow the university's procedure for submitting extension requests or special consideration. Do not send emails to request extensions. Objectives This assessment relates to the Unit Learning Outcomes 1, 3 and 4. It aims to develop and assess students' ability to design ballasted track structure including superstructure and substructure elements. The designs are performed in accordance with relevant railway standards and guidelines. Details & Inputs The geometric design of double-track railway section connecting two stations A and B has been done (in Assessment 1) and now you move on to the structural design of this section. You are required to complete several design options of the track structure and compare the effectiveness of these options. The design should cover the determination of track loadings, design of track superstructure and substructure, comparison of the design options, and the application of geotextiles. The project's specific information and constraints obtained from field surveys and supplied by relevant stakeholders are given as follows: The design period of this railway section is 37 years. The first track on this railway section is designed for the use of two vehicle types with different design speeds, axle loads and annual traffic tonnages as follows: (Vehicle type 1 and 2 if Vehicle type 2 and 3 if t3 3 6 where t is the last digit of the student ID (e.g. t = 1 if the student ID is 987654321) The second track on this railway section is designed for the use of three vehicle types with different design speeds, axle loads and annual traffic tonnages as follows: (Vehicle type 1,2 and 3 if t3 Vehicle type 2, 3 and 4 if 3 6 where t is the last digit of the student ID (e.g. t = 1 if the student ID is 987654321) The wheel diameter of rail vehicles using this railway section is 1016 mm. The tracks are continuous welded rail tracks with welding thickness of 6 mm. Vehicle type Design speed (km/h) The design speed, axle load and annual traffic tonnage of five vehicle types above are given as: Annual traffic tonnage Axle load (tonnes) (tonnes/track) 1 90 13 5x10 2 90 15 4x105 3 90 17 3x105 4 80 19 2x105 5 80 21 1x105 Standard gauge (gauge 1435 mm) is used for both tracks on this railway section. The free rail length used for each track is 27.4 m. The sleeper length is 2.5 m. Two types of sleeper are planned to use for this track with the sleeper materials as follows: The concrete sleeper with 28-day compressive strength fr = 80 MPa. The general duty steel sleeper with the yielding strength fsy = 600 Mpa The ballast material of this track is crushed rock with the Young's modulus, static friction angle and unit weight are as follows: b 280 (MPa), = 45 and y = 16.2 kN/m E = 280 (MPa), = 47 and y = 16.7 kN/m = 550 (MPa), = 49 and y = 17.2 kN/m if t3 if 3 6 where t is the last digit of the student ID (e.g. t = 1 if the student ID is 987654321) The ballast material gradation obtained from the sieve test is given in the table below: Sieve size (mm) Mass passing (kg) Percentage passing (%) 9:46 Back SEN729 2022 Assessment Task 2 -... Questions and Report Content Suggested contents of the report are as follows: Chapter 1: Project Introduction In this chapter, you are required to introduce the design problem, objectives, methodology and interpretation of the design inputs based on your student ID. (0.5 mark) Chapter 2: Track Loadings This chapter focuses on determining different track loadings to be used in the design of track structure. In particular, you are required to complete the following tasks: Task 2.1: Calculate the static wheel loads of all vehicles using the railway section. (1 mark) Task 2.2: Calculate the dynamic wheel loads of all vehicles using the railway section. (1 mark) Task 2.3: Calculate the total number of load cycles applied to each track of the railway section over its design period. (2.5 marks) Chapter 3: Track Superstructure Design This chapter focuses on designing the track superstructure elements. In particular, you are required to complete the following tasks: Task 3.1: Select a single suitable rail size to accommodate the axle loads of both tracks in the railway section and determine the layout gap between two free rail ends. Know that the actual temperature in rails when laid out at the construction site is expected to be 25 C. (1.5 marks) Task 3.2: Calculate the design rail seat load acting on each track of the railway section for two scenarios: (1) when concrete sleepers are used and (2) when steel sleepers are used. (1 marks) Task 3.3: Design the optimal size and spacing of trapezoidal concrete sleepers that can withstand the loads acting on both tracks of the railway section and distribute the loads to ballast. (4 marks) Task 3.4: Design the optimal size and spacing of steel sleepers that can withstand the loads acting on both tracks of the railway section and distribute the loads to ballast. (4 marks) Task 3.5: Calculate the design lateral wheel forces acting on each track of the railway section and check the track derailment condition against lateral track shifting condition. (2 marks) Chapter 4: Track Substructure Design and Geotextiles This chapter focuses on designing the track substructure elements. In particular, you are required to design and compare two options of the track substructure and design the aperture size of geotextile as follows: Task 4.1 (Option 1): Design the thickness of ballast (without sub-ballast) under the trapezoidal concrete sleeper designed in Chapter 3. (3.5 marks) Task 4.2 (Option 2): Design the thicknesses of ballast and sub-ballast under the steel sleeper designed in Chapter 3. (3.5 marks) Task 4.3: Discuss the advantages and disadvantages of Option 1 and Option 2. Note that the discussion should be evidence-based and consider the cost, construction conditions, operation, and environmental effects of two design options (Option 1 and Option 2). You should find relevant journals or conference papers in the literature as evidences of your discussions and refer/cite to them in the report (2 marks) Task 4.4: In case geotextile is used to strengthen the ballast, determine an appropriate aperture size of geotextiles to provide the best interlocking effect with the ballast material. (1.5 mark) Submission Guidelines Your report should follow the structure suggested in the previous section and address the following requirements (2 marks): The report should include title page, table of contents and list of figures and tables. The report should be clear and concise, and provide sufficient explanation and context information for each tasks (NOT just equations or numbers). The report should be written in MS Word or similar software. Scan of hand-writing is NOT accepted (Note: this is for checking plagiarism via Turnitin). All figures should be professionally drawn. Hand-drawings are accepted but they should be clear and at a high quality. Provide number and caption for all tables and figures you created sequentially. Write equations using the equation tool in MS Word or the like (do NOT use plain text). the loads acting on both tracks of the railway section and distribute the loads to ballast. (4 marks) Task 3.4: Design the optimal size and spacing of steel sleepers that can withstand the loads acting on both tracks of the railway section and distribute the loads to ballast. (4 marks) Task 3.5: Calculate the design lateral wheel forces acting on each track of the railway section and check the track derailment condition against lateral track shifting condition. (2 marks) Chapter 4: Track Substructure Design and Geotextiles This chapter focuses on designing the track substructure elements. In particular, you are required to design and compare two options of the track substructure and design the aperture size of geotextile as follows: Task 4.1 (Option 1): Design the thickness of ballast (without sub-ballast) under the trapezoidal concrete sleeper designed in Chapter 3. (3.5 marks) Task 4.2 (Option 2): Design the thicknesses of ballast and sub-ballast under the steel sleeper designed in Chapter 3. (3.5 marks) Task 4.3: Discuss the advantages and disadvantages of Option 1 and Option 2. Note that the discussion should be evidence-based and consider the cost, construction conditions, operation, and environmental effects of two design options (Option 1 and Option 2). You should find relevant journals or conference papers in the literature as evidences of your discussions and refer/cite to them in the report (2 marks) Task 4.4: In case geotextile is used to strengthen the ballast, determine an appropriate aperture size of geotextiles to provide the best interlocking effect with the ballast material. (1.5 mark) Submission Guidelines Your report should follow the structure suggested in the previous section and address the following requirements (2 marks): The report should include title page, table of contents and list of figures and tables. The report should be clear and concise, and provide sufficient explanation and context information for each tasks (NOT just equations or numbers). The report should be written in MS Word or similar software. Scan of hand-writing is NOT accepted (Note: this is for checking plagiarism via Turnitin). All figures should be professionally drawn. Hand-drawings are accepted but they should be clear and at a high quality. Provide number and caption for all tables and figures you created sequentially. Write equations using the equation tool in MS Word or the like (do NOT use plain text). Write proper units of measurements for all calculated values in the report. Harvard style should be used for reference and a reference list should be provided at the end of the report. Marking Scheme The marks allocated for each task are given at the end of the task in each Chapter (1 to 6). Your answer of each task should include sufficient explanations, detailed stepwise calculations and clear drawing or tabulation if required. Not only main calculations but also all relevant checks and justifications related to the design tasks of geometric elements should be performed and presented in the report. 2 marks are allocated to the report presentation. The report must follow and address all the requirements in Submission Guidelines to achieve full marks. End *** 9:46 < Back SEN729 2022 Assessment Task 2 -... The design speed, axle load and annual traffic tonnage of five vehicle types above are given as: Annual traffic tonnage Design speed Vehicle type (km/h) 1 90 2 90 3 90 4 5 80 80 Axle load (tonnes) 13 15 17 19 21 (tonnes/track) 5105 4x105 3105 2x105 1x105 Standard gauge (gauge 1435 mm) is used for both tracks on this railway section. The free rail length used for each track is 27.4 m. The sleeper length is 2.5 m. Two types of sleeper are planned to use for this track with the sleeper materials as follows: The concrete sleeper with 28-day compressive strength f = 80 MPa. The general duty steel sleeper with the yielding strength fsy = 600 Mpa The ballast material of this track is crushed rock with the Young's modulus, static friction angle and unit weight are as follows: b 280 (MPa), = 45 and y = 16.2 kN/m if b 280 (MPa), = 47 and y = 16.7 kN/m if t3 3 6 where t is the last digit of the student ID (e.g. t = 1 if the student ID is 987654321) The ballast material gradation obtained from the sieve test is given in the table below: Sieve size (mm) Mass passing (kg) 63 100 50 85 40 65 32 47 25 28 20 17 16 12 Percentage passing (%) 100 85 65 47 28 17 12 If the sub-ballast is present in the track structure, the provisional ratio of ballast thickness to sub- ballast thickness is chosen as H/Hc = 1.5. If the sub-ballast is present in the track structure, the sub-ballast material is fine gravel with Young's modulus E 72 MPa. The subgrade is fat clay (CH) with the compressive strength = 95 kPa, shear strength s = 35 kPa and Young's modulus E, 28 MPa. The depth of subgrade from ground surface level to the surface of the nearest rock layer is 2 m. The allowable subgrade plastic strain Epa = 2%. . The allowable total subgrade plastic deformation Pa = 25 mm. The temperature at the local area of construction site generally ranges from 5 C to 45 C. The maximum lateral track defect is 5 mm. The dynamic load and rail seat load acting on the tracks must be obtained using the AREMA method. The bending moments in sleepers and sleeper-to-ballast contact pressure have to be calculated using the Australian empirical method. Other required information can be reasonably assumed in accordance with relevant design standards and guidelines. Questions and Report Content Suggested contents of the report are as follows: Chapter 1: Project Introduction In this chapter, you are required to introduce the design problem, objectives, methodology and interpretation of the design inputs based on your student ID. (0.5 mark) Chapter 2: Track Loadings This chapter focuses on determining different track loadings to be used in the design of track structure. In particular, you are required to complete the following tasks: Task 2.1: Calculate the static wheel loads of all vehicles using the railway section. (1 mark)