GENERAL PLANS and DETAILS (Not Inc. Grading + SW) Flashcards Preview

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Flashcards in GENERAL PLANS and DETAILS (Not Inc. Grading + SW) Deck (41)
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1
Q

Layout method for complex angular and curvilinear designs

A

Angles, bearings, and arcs

2
Q

Dimension lines are extended from an object at a ___ angle

A

90 degree

3
Q

Best pH for most plants

A

6.0 - 7.5

4
Q

Diameter of a tree 4” or less measured 6” above the ground

A

Caliper

5
Q

Layout Plan: Problem associated with under-dimensioning

A

Greater interpretation by the contractor / loss of control of the design

6
Q

Layout Plan: Problem associated with over-dimensioning

A

Greater potential for error or confusion; implies an inflexibility in accommodating field conditions

7
Q

Hierarchy of Dimensioning

A

Fixed dimensions > Semi-fixed dimensions > Flexible dimensions

8
Q

Dimension type that locates features w/ high level of accuracy; Usually for legal purposes; Typically located by a licensed land surveyor

Also BASELINES; defines features w/ semi-fixed locations

e.g. property lines, ROW, building locations, setbacks, and other aspects governed by code requirements)

A

Fixed dimensions

9
Q

Dimension type for points, lines, or planes located by fixed dimensions (baselines)

Used to locate most landscape improvements

A

Semi-Fixed Dimensions

10
Q

Dimension type used to locate site elements that do not require precision and / or may be adjusted based on field conditions

May uses ‘+/-‘ or ‘VIF’

A

Flexible Dimensions

11
Q

Dimensions that can be determined only after construction has progressed to a point where an actual measurement can be taken

A

Field Dimensions

12
Q

Level of precision is usually assumed to be:

A

½ of the smallest unit indicated

e.g 84’-3” = +/- ½” precision

When dimensions are provided as a decimal (e.g. 84.25ft, eg) assumed precision is ½ of the lowest decimal point (e.g. .005ft)

Degree of precision should reflect realistic tolerances that can achieved in construction of a particular feature / material

13
Q

Identifies the distance bw two points

A

Dimension Line

  • Should be heavier in weight than dimension lines
  • Should not be broken
14
Q

Extend at a right angle from the dimension line to the object measured

A

Extension Line

Should be lighter in weight than dimension lines

15
Q

Convention of locating dimension line labels

A
  • Above the dimension line

- Read from bottom right hand side of sheet

16
Q

Horz. Layout Method:

Used when a considerable % of side elements are orthogonal to the Fixed Features (PL, new / ex. Building, etc)

Baselines (e.g. building walls) serve as reference points from which objects are measured

String / chain dimensions are closely associated w this method

A

Perpendicular Offsets

17
Q

Horz. Layout Method:

Often used w/ curvilinear elements that do not require a high degree of accuracy

Uses offsets at fixed intervals taken from a baseline to the edge or centerline of an element

Accuracy of the shape is limited by the offset interval

A

Baseline System

18
Q

Horz. Layout Method:

Distances provided along an X,Y axis to provide unique geographical positions of points from a known POB or PO (point of origin)

A

Coordinate System

19
Q

Horz. Layout Method:

Latitude (N-S); departure (E-W)
Either a bearing angle or a length is provided for ea. Point (but not both)

A

Latitude and Departure

20
Q

Horz. Layout Method:

Used for the layout of complex curvilinear designs

Bearing: direction of a line specified by a given angle bw the line and an established meridian

Arc: segment of a circle; defined by a center point, a radius and an internal angle; its end points and orientation must be defined

A

Angles, Bearings, and Arc

21
Q

Horizontal Curve Type:

Two curves in the same direction connected by a tangent; to be avoided in road design

A

Broken-back curve

22
Q

Horizontal Curve Type:

Single radius; most commonly used for low speed roads

A

Simple curve

23
Q

Horizontal Curve Type:

Two or more radii in the same direction; difference in the length of the radii should not be more than 50%

A

Compound

24
Q

Horizontal Curve Type:

Two arcs in opposite directions; usually requires a tangent between them

Length of tangent depends on road’s design speed

A

Reverse curve

25
Q

Horizontal Curve Type:

Typical curves for high speed roads entail a series of curves with a constantly changing radius

A

Spiral Transitional Curves

More difficult to calculate and lay out; typically not used by LAs since it is primarily for high speed roads

26
Q

Marks the beginning of the curve at which the road alignment diverges from the tangent line in the direction of stationing

A

Point of Curvature (PC)

27
Q

Marks the end of the curve at which the road alignment returns to a tangent line in the direction of stationing

A

Point of Tangency (PT)

28
Q

Where two tangent lines intersect

A

Point of Intersection (PI)

29
Q

Central angle of the curve; equal to the deflection angle between the tangents

A

Included Angle (I)

30
Q

Distant from the PI to either the PC or the PT; always equal for simple circular curves

A

Tangent Distance (T)

31
Q

Distance from PC to PT measured along a straight line

A

Chord (C)

32
Q

Point about which the included angle (I) is turned

A

Center of Curve (O)

33
Q

Used in surveying linear routes (e.g. streets, power lines, stationary storm sewers, etc)

Marked along a centerline from a starting point (0+00)

Full station intervals are indicated along a center line; key areas will also be indicated

A

Stationing

34
Q

In stationing, FULL stations are at ___ intervals

A

100 ft (represented at 1+00)

35
Q

In stationing, HALF stations are at ___ intervals

A

50 ft (represented at 0+50)

36
Q

Forward sight distance should not be ___

A

Less than the safe stopping distance for the design speed of the curve

37
Q

Banking / tilting to compensate for centrifugal forces acting on a vehicle as it travels around a curve

A

Superelevation

38
Q

BVC

A

Beginning of vertical curve

39
Q

PVI

A

Point of vertical intersection

40
Q

EVC

A

End of vertical curve

41
Q

(2) Types of Vertical Sight Distance

A
  1. Safe stopping distance
  2. Safe passing distance

(LA’s typically only address stopping distances)