Curb Ramp Construction 2019

Module A

ADA Removal Limits

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The Contractor and the Engineer shall work together to construct all pedestrian facilities to meet the requirements set forth in the plans.

ADA Removal Limits

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(1) Removals - The Contractor and the Engineer shall use the appropriate ramp, sidewalk, and driveway details in the Plan, and calculate the removal limits for the sidewalk and curb and gutter. If it is determined the removal limits will exceed the plan removal limits by more than 10 ft. and the plan removal limits are not adequate to meet PROWAG and MnDOT Standards, the Contractor shall consult with the Engineer to determine a solution. Once the Engineer and the Contractor reach an agreement on how to proceed, the Contractor may finish the removals.

ADA Removal Limits

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ADA Removal Limits

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More complex removal limits typically have steep slopes and at least one tie-in elevation.

ADA Removal Limits

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Calculating removal limits.

5’x7%= 0.35’

5’x1%=0.05’

6’x4%= 0.24’

0.64’

5’x1%=0.05’ 6’x4%= 0.24’

0.29’

Total rise 0.93’ Total run 27’

ADA Removal Limits

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Landings required if the approaching sidewalk is inverse grade, also avoid “Tenting” of sidewalk.

ADA Removal Limits

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Verify removal limits will provide positive drainage as well as maintain existing drainage patterns.

ADA Removal Limits – Transition Panels

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Standard Plans Sheet 5 of 6. • The maximum rate of cross slope transitioning is 1 linear Ft. of

sidewalk per half percent cross slope.• When PAR width is greater than 6’ or the running slope is greater

than 5%. Double the calculate transition length.

1.5%

4.5%

ADA Removal Limits

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If a secondary landing is necessary, check to see if a transition panel will also be needed to make the landing compliant.

LandingLandingTransitionPanel (S)

ADA Removal Limits

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Once the Engineer and Contractor reach agreement on how to proceed, the contractor may finish removals.

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ADA ConstructionConstruction Lessons Learned

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ADA Construction Ramp Compliance

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ADA Construction APS Compliance

64%

73%

82%

93%

99% 99%98%

99%

97%98%

97%99%

71%

84%

90%

95%

81%

77%

84%

97%

87%

96%

91%

95%

60%

65%

70%

75%

80%

85%

90%

95%

100%

2010 2011 2012 2013

Com

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ttrib

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Tota

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mps

Construction Year

Compliant Curb Ramp Attributes by Percentage

Landing Slope

Landing Top ofRamp

Landing Min 4' x 4'

Ramp Cross Slope

Drainage

VerticalDiscontinuties

ADA Construction Non-Compliance

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Separate Landing Placements ReinforcementTo ensure initial ramps and landings are properly constructed, landings shall be cast separately. Follow sidewalk reinforcement detail.

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Separate Landing pour Fan Ramp options with sidewalk reinforcement.

Separate Landing Placements Reinforcement

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Separate Landing Placements GradingIf all grading materials are in place and fully compacted the landing can be placed at the same time as the curb provided curb mix 3F52 is used.

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Why Separate Landing Placements?

Exceeds 3/16” max

Designed grade break in front of PB

When landings are not placed separately it increases the possibility grade breaks will not be located properly.

Grade breaklocation as finished

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All grade breaks within the PAR shall be perpendicular to the path of travel (See Notes Standard Plans sheets 1 & 2)

Grade breaklocation as finished

Design grade breaklocation

Why Separate Landing Placements?

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Why Separate Landing Placements?

Concrete construction or contraction joints need to be located at grade breaks.

Example of concrete that cracked at the grade break location and not at the tooled joint.

ADA Construction Grade Breaks• Specifications for Construction 2521.3D2• Provide vertical and straight joints parallel with or at right angles to the walk centerline

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ADA Construction Grade Breaks• Specifications for Construction 2521.3D2 • Align the joints with joints in adjoining work unless isolated by a ½” preformed joint filler.

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ADA Construction Grade BreaksFan Ramp constructed with incorrect grade break (not perpendicular to the path of travel)

Grade break should be parallel to back of curb

Grade breaklocation as finished

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ADA Construction Grade BreaksFan Ramp constructed with incorrect grade break (grade break needs to be parallel to back of curb).

7’4’

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ADA Construction Grade BreaksAll grade breaks within the PAR shall be perpendicular to the path of travel.(See Notes Standard Plans 5-297.250 Sheets 1 & 2).

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ADA Construction Grade BreaksAll grade breaks within the PAR shall be perpendicular to the path of travel (See Notes Standard Plans 5-297.250 Sheets 1 & 2).

ADA Construction Grade Breaks

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3’4’

The outside edges of the ramp differ in length, thus no perpendicular grade break to path of travel. The grade break at the top and bottom of ramps should be parallel.

ADA Construction Grade BreaksFan Ramp constructed incorrectly with no defined landing or perpendicular grade breaks.

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Standard Plans 2017

Standard Plans Legend

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ADA Curb Ramp Standard Plans

LandingS

LandingS

S

F

F

Landing SS

Indicates pedestrian ramp – slope shall be between 5% minimum and 8.3% maximum in the direction shown and the cross slope shall not exceed 2%.

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ADA Curb Ramp Standard Plans

LandingS

LandingS

Indicates pedestrian ramp – slopes shall be greater than 2% and less than 5% in the direction shown and cross slope shall not exceed 2%.

F

F

F

Landing SS

F

F

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ADA Curb Ramp Construction2% ramp was constructed with landing lower than top of curb.

2.0%

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ADA Curb Ramp Construction

Ramp at 2%

Flat ramp created a drainage valley/swale.

This ramp should have risen up to better match 4’’ curb height to maintain better drainage and eliminate v-curb.

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ADA Curb Ramp Construction• Curb ramp is complaint, but it fits poorly into its surroundings, and will be difficult to maintain.

2%

Landing2.0% 2%

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ADA Curb Ramp Construction

2%-5%

Landing7.0% 2%-5%

• Slopes shown are preferred and side slopes could have been grade, thus eliminating V-curb.

ADA Curb Ramp Construction

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3) After the curb has been correctly poured, the Contractor has set the sidewalk forms, and prior to placing the concrete curb ramps/sidewalks, the Contractor shall verify the requirements in S-1.1B will be achieved.

In addition, the longitudinal slopes shown in the Construction Plans and the Standard Plans shall be utilized unless these conditions cannot be met. The starting point for setting the forms on the controlling ramp leg, landing, and sidewalk slopes should be the following:

Steep (S) = 7%Flat (F) = 4%Landing = 1%Sidewalk Cross Slope = 1.5%Fan ramp = 4%

Special Provisions 1804 Prosecution of Work (ADA)

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ADA Curb Ramp ConstructionWhenever possible, set grades to work

within concrete finishing tolerances.

7%

1%4%

1.4%

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ADA Curb Ramp ConstructionTable curb if necessary. Determine controlling elevation (usually lowest elevation) and set at 7%.

7%

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ADA Curb Ramp ConstructionVerify ramp length, landing dimensions, push button location, and perpendicular grade breaks.

7%Landing

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ADA Curb Ramp ConstructionVerify landing is connected to the PAR with perpendicular grade breaks.

7%Landing

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ADA Curb Ramp ConstructionEstablish both landings with perpendicular grade breaks, verify intermediate ramp is between 2% and 5%.

7%

Landing

2-5% (F)

Landing

(F)

(S)

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ADA Curb Ramp Construction

1.5%

3.5 %

Perpendicular ramp adjacent to concrete pavement with gutter flow line that exceeds 2%. Make correction over the entire length of the ramp.

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Landing5%

Grade Breaks

ADA Curb Ramp Construction

2%

Fan ramp adjacent to concrete pavement constructed with a greater than 2% gutter flow line.

ADA Curb Ramp V-Curb• V-curb follow Standard Plans (sheet 5 of 6) for design and construction.

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ADA Curb Ramp V-Curb• Note (3) Edge between new v-curb and in-place structure shall be sealed and bond breaker shall be used between existing structure and placed v-curb.

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ADA Curb Ramp V-Curb

• Work next to existing building or structures.

½’’ expansion wasIncorrectly placed here

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ADA Curb Ramp V-Curb• Construct with a vertical face.• Always 4” width v-curb when

adjacent to building.

9”

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Roundabouts and Median Islands• Pedestrian Approach Nose Detail

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Roundabouts and Median Islands• Use Pedestrian Approach Nose Details at all four

corners. Follow reinforcement details if not poured integral with curb and gutter or with V- curb.

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Roundabouts and Median Islands• Recommendations from the NCHRP (National Cooperative Highway

Research Program).• At ramps located where slip ramp “T” into trail place domes at the

top of ramp. • At locations where trail comes off roadway, place domes in the

direction of travel.

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Roundabouts and Median Islands• Roundabout and Bicycle slip

ramps.• Place the domes in the direction

of travel and domes should provide visual contrast.

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ADA Construction

Questions ?

Questions ?

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ADA Construction

Questions ?