Objectives

This assessment item relates to the unit learning outcomes 1, 2, 5 and 6. It develops students' ability to understand capacity analysis procedures for both roadways and intersections using current Australian Guidelines and Design Practices. Use of SIDRA software (intersection design software) is highly recommended when applicable..

Quizzes (6 Marks):

Complete Moodle quizzes

Roadway Capacity Analysis Task (10 Marks)

Road Authority in Victoria is currently considering to upgrade an existing Class I two-lane two-way road to a freeway in order to improve traffic operations. As a traffic engineer working at Road Authority in Victoria, you were asked to collect data for the existing condition, analyse the existing condition and recommend whether converting Class I two-lane two-way road to freeway improves capacity and level of service. Over several months, you collected the following data:

Existing Class I two-lane two-way road:

• Rolling terrain
  
• Demand volume: (2000 + last four digits of your student ID ÷ 10) rounded to nearest 10 (total in both directions)
  
• Directional split: 60/40
  
• Peak hour factor (PHF)= 0.90
  
• 40% no-overtaking/passing zones in the analysis segment (both directions)
  
• 10% trucks and 5% RVs
  
• 11ft (3.3m ) lane widths, 4ft (1.2m) useable shoulders
  
• 10 access points per mile (6.25 per km)
  
• Estimated base free-flow speed: 65mi/hr (100km/hr)
  
• All motorists seem to be commuters or regular facility users.

 Proposed freeway data:

• Lane width of 12ft (3.6m), left-side lateral clearance 3ft (0.9m) and about 4 ramps per mile (2.5 ramps per km)
  
• Two lanes per direction, freeway in rolling terrain
  
• Directional traffic flow is expected to increase by 10% than existing multilane condition including trucks but PHF is expected to remain the same.
  
• All motorists are expected to be commuters or regular facility users.
  

Consider the following types for analysis (ignore the costs of converting Class I two-lane two-way road to freeway):

• Class I two-lane two-way road- existing case (4 marks)
  
• Freeway- proposed (4 marks)
  

Also, compare and provide a detailed discussions on analysis outcomes. (2 marks)

Intersection Capacity Analysis Task (14 Marks)

A City Council received a number of complaints about excessive delays at one of their local street intersection during morning peak period at the City Centre. As a traffic engineer working for the City Council, you were tasked with providing the best engineering solution to remedy the problem (if there is a problem). You performed a site visit and the following observations were made:

• The intersection connects two-lane two-way cross-roads at approximately 90 degree angle.
  
• There is a right-turning lane on North-South road in both directions. But site condition is such that one right-turn lane could be added in both directions on East-West road too but there is no space for left-turning slip lanes or additional through lanes. Small roundabout could also be considered.
• There were virtually no trucks during morning peak period.
• Currently, the intersection is un-signalised and East-West road needs to GIVE WAY to North-South traffic.
• Speed limit is 60km/hr at all approaches.
• There is not much variation of traffic flow rate within morning peak hour.
• Traffic volumes (veh/hr) during the peak period were observed as follows:
• From South: 100 (left turn), 500 (through) & 100 (right turn)
• From East: 100 (left turn), 100 (through) & (100+ last four digits of your student ID÷100) (rounded to nearest 10) (right turn)
• From North: 100 (left turn), 500 (through) & 100 (right turn)
• From West: 150 (left turn), 100 (through) & 200 (right turn)
• No annual traffic growth is expected for foreseeable future.
  
• Other information can be assumed within Australian Standards and guides

 Consider the following types of intersections for manual analysis and design:

• Un-signalised intersection- existing case (2 marks)
  
• Un-signalised intersection- modified when right turning lanes are added on East-West road (2 marks)
  
• Roundabout (2 marks)
• Signalised intersection (2 marks). Use 1950pc/hr as saturation flow for all lanes, lost time of 3secs, inter-green time of 5secs, minimum display green time of 7secs and practical degree of saturation of 90%.

Compare your manual analytical solutions with the outputs from SIDRA. Provide reason/s if there are any variations in the outputs. (4 marks)

Also compare alternative intersection controls and recommend the best intersection type. (2 marks)

The marking matrix shall be based on the content consisting of the following principles. Each sequential step shall be allocated marks proportionately

1. Accuracy of Input parameter for each computation step with appropriate unit. Marks will only be awarded for correct input
2. Application of accurate methodology with appropriate referencing. Full mark will only be awarded for error free computational steps with appropriate explanation to be understood by an independent person.
3. Accuracy of answer with appropriate unit. Zero mark will be awarded with error in either Input or methodology.
4. If answers to any preceding steps are inaccurate. Partial mark be awarded for subsequent answers.

Additional information should be obtained from the Moodle Unit web-page

Objectives

This assessment item relates to the unit learning outcomes 3, 4, 5 and 6. It develops students' ability to understand Australian pavement design system, materials and tests and design of alternative pavement configurations (flexible pavements, rigid pavements and structural overlays) using current Australian Guidelines and Design Practices. Use of CIRCLY software (pavement design software) is highly recommended when required.

Quiz (6 Marks)

Complete Moodle quiz

Design Tasks: Background Information

Geometric design, earth moving and subgrade evaluation of a new two-lane two-way road has been recently completed and now it is time for design of pavement in Victoria. The following are the project specific information supplied by the client (Road Authority in Victoria):

• Two way total AADT= 3000+the last four digits of your student ID÷10 (rounded to nearest 10)
  
• Pavement design period 25 years.
• Project reliability 97.5%.
• Lane width= 3.5m.
• Directional distribution: 70/30
• Subgrade CBR value = 3% (if the last four digits of your student ID is < 3000), 5% (if the last four digits of your student ID is ≥ 3000 but < 6000) and 7% (if the last four digits of your student ID is ≥ 6000)
• Heavy vehicles = 8% (if the last four digits of your student ID is < 3000), 9% (if the last four digits of your student ID is ≥ 3000 but <6000) and 10% (if the last four digits of your student ID is ≥6000)
• Annual heavy vehicle growth is 1% throughout the design period
• Other required information can be assumed within Australian Standard (Austroads Guides)

Design Task 1: Pavement Design Input Parameters (2 marks)

• Summarise and calculate ALL input parameters for both flexible and rigid pavement designs (2 marks)

Design Task 2: Flexible pavement design (10 marks)

Design the following flexible pavement alternatives using empirical or empirical-mechanistic procedures (as applicable, appropriate or preferred!). You need to draw final design drawings for all cases (not to scale is acceptable but indicate all required dimensions and units of measurements). You must discuss/interpret everything you calculate or present.

• Flexible 1: Unbound granular pavement with thin bituminous surfacing (2 marks)
  
• Flexible 2: Full depth asphalt (E=3000MPa), surface layer asphalt (E=2200MPa) (2 marks)
• Flexible 3: Asphalt (E=3500MPa) with granular base (E=500MPa) (3 marks)
• Flexible 4: Asphalt (E=2500MPa), cemented base (E=3000MPa) and granular subbase (E=550MPa (3 marks)

Design Task 3: Rigid Pavement design (8 Marks)

Design the following rigid pavement alternatives using analytical or graphical methods (as applicable or appropriate or preferred!). You need to draw final design drawings for all cases (not to scale is acceptable but indicate all required dimensions and units of measurements). You must discuss/interpret everything you calculate or present.

• Rigid 1: PCP pavement with  concrete shoulder (4 marks)
  
• Rigid 2: CRCP pavement without concrete shoulder (4 marks)
  

Design Task 4: Design of Flexible Asphalt Overlay (3 Marks)

A homogeneous section of a cracked asphalt surfaced granular pavement is situated in Melbourne where the WMAPT is 24°C. As the existing asphalt is cracked, it is proposed to mill 25mm from the existing 50mm thick asphalt prior to asphalt overlay. The following characteristic values were calculated from deflectograph deflection testing undertaken at a pavement temperature of 25°C: 

• Measured Characteristic Deflection at 25°C = 0.47 mm 
• Measured Characteristic Curvature at 25°C = 0.180 mm. 
  

Based on experience, the client (Road Authority in Victoria) advised that the designer considered that there was no need to apply a Seasonal Moisture Correction Factor to these measured deflections and curvatures. The design traffic loading (ESA) for this section is the same as described above (Design Task 1).

• Overlay: Design asphalt overlay on asphalt surfaced granular pavement using design charts. You need to draw final design drawings (not to scale is acceptable but indicate all required dimensions and units of measurements). You must discuss/interpret everything you calculate (3 marks)

Note: 2 marks is allocated for submission guidelines, e.g., file type, sequence, referencing, units of measurements, flow of information, etc.

The marking matrix shall be based on the content consisting of the following principles. Each sequential step shall be allocated marks proportionately

1. Accuracy of Input parameter for each computation step with appropriate unit. Marks will only be awarded for correct input
2. Application of accurate methodology with appropriate referencing. Full mark will only be awarded for error free computational steps with appropriate explanation to be understood by an independent person.
3. Accuracy of answer with appropriate unit. Zero mark will be awarded with error in either Input or methodology.
4. If answers to any preceding steps are inaccurate. Partial mark be awarded for subsequent answers.

Additional information should be obtained from the Moodle Unit web-page

• You will complete the practical activities and the laboratory report as a team.
• Each team should check their schedule timetable as shown in Moodle
• All teams will upload a single team report due as per the Unit Profile.
• The required practical activities are as follows

1. Preparation of disturbed soil sample for testing
2. Soil Compaction and density test AS1289.5.2.2017
3. Determination of Permanent deformation of unbound granular materials under undrained contions AGTP-T053-07
4. Determination of Resilience Modulus characteristics of unbound granular materials under undrained contions AGTP-T053-07
5. Lime Saturation Point of Soil (pH Method) RC131.01 2018

The marking matrix shall be based on the content consisting of the following principles. Each sequential step shall be allocated marks proportionately

1. Accuracy of Input parameter for each computation step with appropriate unit. Marks will only be awarded for correct input
2. Application of accurate methodology with appropriate referencing. Full mark will only be awarded for error free computational steps with appropriate explanation to be understood by an independent person.
3. Accuracy of answer with appropriate unit. Zero mark will be awarded with error in either Input or methodology.
4. If answers to any preceding steps are inaccurate. Partial mark be awarded for subsequent answers.

Additional information should be obtained from the Moodle Unit web-page