Geometric Design

1
Geometric Design

• ?????????????? ????????
• ??????????????????? ?????????????????
• ??????????????????????????

2
????????????????????????????????????????

• ?????????????? ??????????????? 7 20 ??
• ?????????????????
• ???????????????????
• ???????????????????? ????????? ???????????
  ????????? ????????? ?????????????? ??????????
  ?????????????????? ???????

3
Minimum Design Standard for Highway
4
???????????????????????????

• ????????????
• ??????????????????????????????????????????????
• ??????????????????????????????????????????????
• ????????????????????????? 2 ?????????????????????
  60 ????
• ????????????? 1?????????????????????

5
Horizontal Alignment

• ????????????????????????????????????????? 30 ????
• ????????????????????????????????? ???
• ??????????????????????????????
• ?????????????????????????????????????????
• ???????????????????????????????????????
  ???????????????????????
• ?????????????????????????????????????????????
  Spiral
• ??????? Stopping Sight Distance

6
Horizontal Curve Design

• Degree of Curve
• ??????? 5 7 ???? ?????????? 10 ?????????????

7
Circular Curve or Simple Curve
8
Curve Calculation

• ???? Tangent , T R tan ?/2
• PC. Station PI T
• ????? L R? (rad.)???? ?R??/180
• PT PC L
• ???????? D ????????????????????? 100 ????? D?
  5730/R ?????????????? 20 ?. ??????????????????????
  ??????? 20x5730/R/100

9
Curve Calculation (Contd)

• ?????????????????????????????????
• ????????????????????(D1, Dn)??????????????????????
  ?????????
• ????? Station ??????????????????

10
Compound Curve
11
Compound Curve
12
Broken Back Curve
13
Reverse Curve
14
Spiral Curve
15
Spiral Curve
16
Spiral Curve
17
Ex.7.1
18
Sight Distance

• ?????????????????????????????????
  ????????????????

19
Horizontal Sight Distance

• Safe Stopping Distance
• Perception and Reaction Distance

20
Horizontal Sight Distance

• Safe Stopping Distance
• Breaking Distance

21
Horizontal Sight Distance

• Safe Stopping Distance
• ????????????? (S ???????????)

22
Safe Stopping Distance

• ??????????????? 7.3 ???????????????????????
• ?.?.7.2 7.3

23
Passing Sight Distance

• ??????????????????????????????

24
Passing Sight Distance
25
???????????????????????????????

• ??????? 1 S lt L ??????????????????????????????

26
???????????????????????????????

• ??????? 2 S gt L

27
Ex.7.4, 7.5

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