Flexible Pavement Design (JKR Method) BFC 31802 IGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin CHAPTER 3 PAVEMENT DESIGN: Flexible Pavement Design (JKR Method)

FACTORS THAT INFLUENCE PAVEMENT DESIGN BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin FACTORS THAT INFLUENCE PAVEMENT DESIGN Traffic Loading Magnitude of axle load Wheel configuration Volume and composition of axle loads Tyre pressure and contact area (2) Material Characteristics (3) Climate or Environment

DETERMINATION OF DESIGN TRAFFIC BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin DETERMINATION OF DESIGN TRAFFIC Traffic data is a key input for structural design of pavements. Standard axle or wheel load Traffic spectrum and traffic volume – standard axle during design life Equivalent Standard Axle Load (ESAL) in Malaysia – 80 kN Commercial vehicle (CV) CONSIDERATION OF TRAFFIC DATA Number of CV during Year 1 of Design Period – is the expected completion of construction Vehicle class and axle distribution Directional and lane distribution factors Traffic Growth factors

Single Axle Tandem Axle Tridem Axle Traffic Loading BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin Single Axle Tandem Axle Tridem Axle Traffic Loading

Load Factor LS = 80kN, 8.16 tonne, 18,000 lb Lorry 9 tonnes BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin Load Factor LS = 80kN, 8.16 tonne, 18,000 lb Lorry 9 tonnes Car 1.5 tonne Bus 18 tonnes Trailer 26 tonnes

Material characteristics BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin Material characteristics a) Equal thickness Different material Different resultant pressures b) Different thicknesses Different material stiffnesses Equal resultant pressure * It shows how materials characteristics affect the thickness design

/ / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin Climatic / Environmental Effect / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / Seepage from highlands Water ponding Seepage through shoulder Seepage through pavement Water content rises in subgrade Subgrade looses strength and stability If subgrade is too weak, pavement will fail

JKR ARAHAN TEKNIK (JALAN) 5/85 DESIGN METHOD BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin JKR ARAHAN TEKNIK (JALAN) 5/85 DESIGN METHOD PROCEDURE: Design life is usually taken as 10 years. Traffic Estimation: Initial Annual Commercial Vehicle Traffic per direction, Vo where ADT = average daily traffic Pc = percentage of commercial vehicles D = directional distribution (usually 0.50) L = lane distribution (usually 1.00)

Total Number of Commercial Vehicles per direction, Vc BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin Total Number of Commercial Vehicles per direction, Vc where r = traffic growth rate x = design life Total Equivalent Standard Axles, ESA ESA = Vc x e where e = equivalent factor (Table 3.5) Daily Traffic Flow at the end of the design period, Vx Vx = V1 (1 + r)x where V1 = ADT / 2 (per direction)

Maximum Hourly Capacity, c c = I x R x T BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin 3. Capacity Estimation Maximum Hourly Capacity, c c = I x R x T where I = ideal hourly capacity (Table 3.6) R = roadway reduction factor (Table 3.7) T = traffic reduction factor (Table 3.8) Daily Capacity, C C = 10 x c (assume c is 10% of C) Check C > Vx If C > Vx  capacity will not be exceeded at the end of the design period (OK) If C < Vx  capacity will be exceeded by the end of the design period (not OK) When C < Vx happens, need to reduce design period. Years required to reach capacity,

Calculate thickness, TA. TA = a1 D1 + a2 D2 + a3 D3 BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin Calculate thickness, TA. TA = a1 D1 + a2 D2 + a3 D3 where a1, a2, a3 = structural coefficients (Table 3.9) d1, d2 , d3 = layer depth (based on Tables 3.10, 3.11, 3.12) 5. Determine the equivalent thickness, TA’ using Thickness Nomograph Based on subgrade CBR, ESA and TA values (Figure 3.5). If CBR varies within the 1 m depth of the subgrade, the mean CBR is calculated: Make sure TA > TA’

BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin Let’s try Example Yeah!

The following conditions are given:- Class of road = R5 BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin EXAMPLE CALCULATION   Question: The following conditions are given:- Class of road = R5 Initial daily traffic volume (ADT) = 6,600 Percentage of commercial vehicles = 15% Annual growth rate = 7% Equivalence factor = 2.0 Subgrade CBR = 5% Rolling terrain

Table 3.5: Guide for Equivalence Factor BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin Table 3.5: Guide for Equivalence Factor Percentage of selected heavy goods vehicles 0 – 15% 16 – 50% 51 – 100% Type of road Equivalence Factor Local 1.2 Trunk 2.0 3.0 3.7 Table 3.6: Maximum Hourly Capacity under ideal conditions Road Type Passenger Vehicle Unit per hour Multilane Two Lanes (bothways) Three Lanes (bothways) 2000 per lane 2000 total for bothways 4000 total for bothways

Table 3.7: Carriageway Roadway Reduction Factor Carriageway Width BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin Table 3.7: Carriageway Roadway Reduction Factor Carriageway Width Shoulder Width 2.00 m 1.50 m 1.25 m 1.00 m 7.5 m 7.0 m 6.0 m 5.0 m 1.00 0.88 0.81 0.72 0.97 0.86 0.78 0.70 0.94 0.83 0.76 0.67 0.90 0.79 0.73 0.64 Table 3.8: Traffic Reduction Factor Type of Terrain Factor Flat Rolling Mountainous T = 100/(100+Pc) T = 100/(100+2Pc) T = 100/(100+5Pc)

Table 3.9: Structural Layer Coefficient Component Type of Layer BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin Table 3.9: Structural Layer Coefficient Component Type of Layer Property Coefficient Wearing and Binder Course Asphalt Concrete 1.00 Base Course Dense Bituminous Macadam Type 1 : Stability > 400 kg 0.8 Type 2: Stability > 300 kg 0.55 Cement Stabilized Unconfined compressive strength (7 days) 30 -40 kg/m2 0.45 Mechanically Stabilized crushed aggregate 80% 0.32 Subbase Sand, Laterite etc 20% 0.23 Crushed aggregate 30% 0.25 60% 0.28

Table 3.10: Structural Layer Coefficient Type of Layer BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin Table 3.10: Structural Layer Coefficient Type of Layer Minimum Thickness Wearing Course 4 cm Binder Course 5 cm Base Course Bituminous Wet Mix 10 cm Cement Treated Subbase Granular 15 cm

Total thick of bituminous layer BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin Table 3-11: Standard and Construction Layer Thickness Type of Layer Standard Thickness One layer lift Wearing Course 4-5 cm Binder Course 5-10 cm Base Course Bituminous 5-20 cm 5-15 cm Wet Mix 10-20 cm 10-15 cm Cement Treated Subbase Granular 10-30 cm 15-20 cm Table 3.12: Minimum Thickness of Bituminous Layer TA Total thick of bituminous layer < 17.5 cm 17.5 – 22.5 cm 23.0 – 29.5 cm > 30.0 cm 5.0 cm 10.0 cm 15.0 cm 17.5 cm

BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr BFC 31802 HIGHWAY ENGINEERING Lecturer: Mr. Mustafa Kamal bin Shamshuddin