study on economic partnership projects

3-27:
Major geometric specifications for interchange are summarized in the following Table
Table 3-27 Geometric Specifications for Interchange
Item Unit
3-57
Design Speed (km/h)
100 120
Deceleration Lane m 90 100
Acceleration Lane m 180 200
Source: TCVN5729-2007
Taper m 60 75
Other categories and classes of alignments such as ramp way are designed referring to
Highway Design Standards TCVN4054-2005. Design speed of 40 km/h will be applied for ramp
way following that of adjacent expressways. The major geometric specifications for ramp way are
summarized in the following Table 3-28:
Vertical Curve
Minimum
Radius
Crest
Sag
Table 3-28 Geometric Design Standards for Ramp Ways
Item Unit
Design Speed Km/h
minimum m 60
normal m 125
Maximum Grade % 7
Radius of Curve
40
minimum m 700
normal m 1,000
Length of Curve m 35
Radius of Curve
minimum m 450
normal m 700
Length of Curve m 35
Maximum superelevation % 8
Maximum Radius which allows inverse superelevation m 600
Minimum stopping sight distance m 40
Source: TCVN4054-2005
(c) Typical Cross Section
Typical cross section is designed in accordance with TCVN5279-2007 and in consistency
with adjacent expressways.
i) Typical Cross Section of Main Road and Frontage Road
Main road consists of 3.75 m x 3 lanes, emergency stopping lane of 3.0 m, median of 1.0 m,
inner safety strip of 0.75 m and shoulder width of 1 m per one direction (Figure 3-42). Hence, the
total width is 33 m. Frontage road consists of one lane of 3.5 m and 1.0 m shoulder width at both