ii 
Indirect procedure in preliminary survey and design . 
Photographic targets + e e e +. + +e ^ + + 
Initial photography of route . . + +, 
First phases of procedure . . . M Ut + € 
Initial engineering use of photographe and maps 
Intervening surVeys . + + + +++ + . €. + 
Second photography où route... «+ +... ..…. e 
Additional phases of procedure . . . +’. . . 
Compilation of planimetric maps, and measurement of 
cross sections by photogrammetric methods . . 
profile and 
> * 
Accuracy and completeness tests of planimetric maps, and pro- 
file and cross Sections +: . .. "Lets + + a + + 6 
Engineering use of photographs, planimetric maps, and profile 
and cross sections e 5 o ae. ns, +8 + e 79 . 
Applications in the location survey +. . . ..* + a 
Construction engineering . . . . : ee + 
Post-construetion applications of serial Surveys + . 
Maintenance . . . a. e +. ^» ^» * 
Improvement and reconstruction +. +... 
Electronic computers in highway engineering s. à . 
Procurement of aerial photographs and photogrametrically Compiled Raps 
By Contract . . . + +++ + + +4 .+ + + + «+ 
ILLUSTRATIONS 
Controlled access highway 4. 5. . ©» . . 
Aerial surveys determine the best highway vocation . e 
Stereogram 1, route alternatives . + .. . + +» e ^ 5». . 
Stereogram 2, highway route revisions t+ . 2 2. ws 
Stereogram 3, location over rolling farmland . . . . . . 
Stereogram à, location through & suburban area . . . 
Stereogram 5, route between residential and transportation- industriel 
areas i + . . + + eue 
Stereogran 6, route location in rugged, eroded area . . 
Placement of photogrephic targets . . . . . . . . 
Photographic targets . . . . 
Using the spline to project Didmway alineneut . , 
Drainage delineation on vertical photographs . . . 
Stereogram of portion of highway route selected for prelininary 8 Survey 
Divided highway alinement design on i map . 
Ground view of & divided highway 
. . + . 
TABLES 
1. Scales and contours related to topography . . ts id uen ias 
2. Interval of placing photographic targets on seni-peruanent station 
markers . . . e  « 
3. Necessary target Clearance for photography c of various focal lengths 
l. Map scales for preliminary surveys y. 
5. Relief height to flight height ratios of. some double ‘projection 
photogrammetric instruments . "ile Vue 
6. Accuracy in measurement of profile and cross sections . 
15 
16 
17 
18 
18 
19 
2h 
26 
36 
37 
39 
21 
25 
26 
29 
32 
43