PAES 289:2019 Farm to Market Road - Concrete

What does the standard cover?

Design, construction, operation, and maintenance of one-lane and two-lane concrete FMRs.

Maximum ADT covered?

400 vehicles/day or less.

Farm to Market Road

A road connecting agricultural and fisheries production areas, coastal landing points, and postharvest or processing facilities to local roads, national highways, and markets.

Where should FMRs be located?

Within key production areas, marginal lands, or new lands within SAFDZs, CLUPs, and other convergence initiative areas.

What is the main purpose of an FMR?

To improve the movement of agricultural and fisheries products between production areas and markets.

California Bearing Ratio

ratio of test load to an arbitrarily defined standard load, expressed as a percentage.

Equivalent Single Axle Load

conversion of expected axle loads into an equivalent number of 18-kip single-axle loads.

Field Density Test

determines the degree of soil compaction.

What is crossfall?

Transverse slope that allows water to drain from the carriageway.

What is superelevation?

Cross slope provided on horizontal curves to partially counteract centrifugal force.

What is a turnout?

A widened, unobstructed shoulder area where slow-moving vehicles can pull over to allow other vehicles to pass.

What is a weep hole?

An opening in a retaining wall or similar structure that drains water behind or beneath it, reducing hydrostatic pressure.

Meaning of shall?

Indicates a mandatory requirement.

Meaning of should?

Indicates a recommended practice.

Minimum embankment height above flood level?

At least 0.6 m higher than the area's flood level.

Where should roads preferably be constructed?

On elevated portions; avoid swampy, logged-over, and flood-prone areas whenever possible.

What investigations are required before preparing plans?

Traffic analysis, field survey, and geotechnical investigation.

What should determine the road design?

Anticipated traffic volume, design speed, vehicle characteristics, and terrain.

What safety features should be provided?

Traffic signs, side rails, road markings, and other appropriate safety structures.

Level – ADT below 50

50 kph

Level – ADT 50–250

50 kph

Level – ADT 250–400

60 kph

Rolling – ADT below 50

30 kph

Rolling – ADT 50–250

50 kph

Rolling – ADT 250–400

50 kph

Mountainous – all ADT categories

30 kph

Recommended minimum horizontal curve radius?

30 m.

Minimum radius when superelevation is provided at 30 kph?

May be reduced, but should not be less than 25 m.

Maximum grade for level terrain?

8% at 30 kph; 7% at 40, 50, and 60 kph.

Maximum grade for rolling terrain?

11% at 30 and 40 kph; 10% at 50 and 60 kph.

Maximum grade for mountainous terrain?

16% at 30 kph; 15% at 40; 14% at 50; 13% at 60 kph.

Minimum grade for paved surfaces?

0.30%, to facilitate drainage on curbed and cut sections.

When are vertical curves required?

When the algebraic difference in grade is greater than 0.5%.

Minimum vertical curve length?

40 m.

Maximum superelevation?

8%.

Maximum shoulder rollover?

8%.

Minimum tangent for superelevation runoff?

30 m.

Minimum widening on sharp curves?

0.60 m.

Critical lengths of upgrades of 3%

500 m

Critical lengths of upgrades of 4%

340 m

Critical lengths of upgrades of 5%

240 m

Critical lengths of upgrades of 6%

200 m

Critical lengths of upgrades of 7%

170 m

Critical lengths of upgrades of 8%

150 m

One-lane minimum pavement width?

2.5 m

One-lane minimum shoulder width?

0.75 m

Two-lane minimum pavement width?

5.0 m

Two-lane minimum shoulder width?

1.5 m

When is a one-lane roadway appropriate?

For light vehicles and ADT below 50.

Turnout width and length?

Approximately 1 m wide × 60 m long.

Minimum distance between consecutive turnouts?

1,000 m.

Minimum shoulder width in constrained mountainous areas?

May be reduced to 0.6 m.

Shoulder material?

At least gravel surfacing.

Shoulder compaction in the reduced-width case?

100% density, certified by an accredited laboratory.

Minimum carriageway crossfall?

1.5%.

Shoulder slope?

3% from the edge of the carriageway.

Normal side slope?

04:01

Maximum side slope?

02:01

Preferred intersection angle?

90° (right angle).

Acceptable intersection angle in special situations?

45°–65°.

Angles strongly discouraged?

Less than 45°.

Maximum approach grade where practical?

2%.

Minimum length of relatively flat approach?

30 m.

Visibility requirement for roadway speed not exceeding 30 kph?

40 m.

Recommended pavement material?

Portland Cement Concrete (PCC).

Pavement thickness design reference?

AASHTO 1993 Guide for Design of Pavement Structures.

Minimum pavement thickness?

200 mm.

Maximum slab length?

4.5 m.

Recommended slab width-to-length ratio?

Should not exceed 1.25.

General joint spacing guide?

In feet, spacing should not greatly exceed twice the slab thickness in inches.

Weak subgrade CBR?

2% or less.

Minimum subbase thickness for weak subgrade?

150 mm.

Normal subgrade subbase thickness?

80 mm.

Very stable subgrade CBR?

15% or more.

Minimum subbase thickness for very stable subgrade?

0 mm (subbase may not be required).

Additional subbase for CBR 4% or less when heavy construction vehicles use it?

Additional 150 mm.

Additional subbase for other normal subgrades under heavy construction traffic?

Additional 80 mm.

When may a subbase layer be unnecessary?

When roadbed soil is equal in quality to subbase, or design traffic is below 1,000,000 18-kip ESAL.

Purpose of dowel bars?

Transfer loads across transverse joints while allowing joint movement.

Dowel diameter rule of thumb?

Slab thickness × 1/8.

Typical dowel spacing?

300 mm on center.

Typical dowel length?

450 mm.

When should dowels be installed at every contraction joint?

For pavement thickness exceeding 200 mm due to heavy traffic loading.

Purpose of tie bars?

Hold adjacent slabs or lanes together at longitudinal joints.

Tie bar diameter in the referenced spacing table?

12 mm.

Tie bar spacing for slab thickness 200–230 mm?

750 mm.

Tie bar spacing for slab thickness 240–280 mm?

600 mm.

When is an expansion/isolation joint used?

To accommodate differential horizontal movement between pavement and another structure, such as at intersections.

Expansion joint width?

19–25 mm.

How long should an expansion cap cover the dowel?

At least 50 mm.

When is a construction joint required due to interruption?

When paving is interrupted for more than 30 minutes.

When should saw-cut contraction joints generally be made?

Usually 4–24 hours after concrete placement, once sufficiently hardened for sawing.

Minimum design flood of Culvert

20-year

Minimum design flood of Roadside ditches and inlets

5-year

Minimum design flood of Median ditches and inlets

5-year

Minimum design flood of Curb drop inlets

5-year

Minimum check flood of Culvert

50-year

Minimum check flood of Roadside ditches and inlets

10-year

Minimum check flood of Median ditches and inlets

10-year

Minimum check flood of Curb drop inlets

10-year