Agency
Title
Table of Contents, Page 1

Louisiana Department of Transportation
and Development

Work Stream 9:
Maintenance Planning and Budgeting

Level-of-Service Data Collection Manual

November 2006

la09702r05DataCollectionManual051213(5).docLADOTD
021018-12.03Level-of-Service Data Collection Manual

Louisiana Department of Transportation and Development

Level-of-Service Data Collection Manual

Table of Contents

I.Introduction......

A.Purpose......

B.General Approach......

C.Overview of Maintenance Condition Assessment Criteria......

II.Data Collection Procedures......

A.Field Sample Segments......

B.Data Collection Equipment......

C.Safety Responsibility......

D.Data Collection Procedures......

Appendix A: Road Maintenance Feature Inventory and Condition Rating: Data Collection Criteria A-

Appendix B: Roads Maintenance Condition Rating Forms...... B-

Appendix C: Examples of Pavement Distress Surface Areas...... C-

la09702r05DataCollectionManual051213(5).docLADOTD
021018-12.03Level-of-Service Data Collection Manual

1

I.Introduction

A.Purpose

The purpose of this manual is to describe the procedures for collecting data to assess the current condition of roadway features maintained by the Louisiana Department of Transportation and Development (LADOTD). This exercise is part of an overall maintenance program based on condition ratings and level of service.

B.General Approach

The general approach for assessing current condition ratings consists of the following steps:

  • Inventory roadway features maintained by LADOTD and identify the types of measurements or observations needed to assess the condition of each feature. The objective is to include only those features that best represent the overall level of service being provided and to avoid including every possible feature that must be maintained.
  • Establish criteria and develop procedures to rate the condition of each maintenance feature.
  • Conduct office and field training for LADOTD road maintenance personnel. Test procedures and inter-rater consistency at selected locations in the field.
  • Conduct field measurements and observations. Record the data.
  • Establish a database containing the condition assessment data.
  • Analyze the data and establish the current condition rating for each maintenance feature. Estimate the current level of service.
  • Prepare summary reports for developing an annual budget.

At the time this manual was written, the first two steps have been completed.

C.Overview of Maintenance Condition Assessment Criteria

Exhibit I1 illustrates the maintenance groups, maintenance features, and types of measurements and observations needed to assess the condition of each feature.

Exhibit I1: Roadway Maintenance Elements to Determine Condition Ratings

Maintenance Group / Maintenance Feature / Maintenance Condition
Assessment Criterion
Asphalt Pavement /
  • Potholes
  • Rutting
  • Raveling
  • Alligator Cracking
  • Linear Cracking
  • Area Cracking
  • Sweeping
  • Other (bleeding, humps, sags, delamination, etc.)
/
  • Number of potholes per lane mile
  • Linear feet of rutting per lane mile
  • Percentage of surface area distressed
  • Percentage of surface area distressed
  • Linear feet of cracking per lane mile
  • Percentage of surface area distressed
  • Percentage of surface area needing sweeping
  • Number of deficiencies per lane mile

Concrete Pavement /
  • Potholes
  • Spalling
  • Longitudinal / Transverse Cracking
  • Longitudinal Faulting
  • Transverse Faulting / Bumps
  • Sweeping
/
  • Number of potholes per lane mile
  • Number per lane mile
  • Linear feet per lane mile ……..
  • Linear feet per lane mile
  • Number of deficiencies per lane mile …….
  • Percentage of surface area needing sweeping

Shoulders /
  • High Shoulder
  • Edge Rutting
/
  • Linear feet per shoulder mile
  • Linear feet per shoulder mile

Drainage /
  • Pipes and Culverts
  • Drop Inlets and Catch Basins
  • Ditches
  • Curbs & Gutters
/
  • Percentage of pipes damaged or equal to or greater than 50 percent blocked
  • Percentage of drop inlets and catch basins defective
  • Percentage of ditch length defective or impeding flow
  • Percentage of gutter length defective

Roadside /
  • Erosion Control …….
  • Noxious Weeds
  • Mowing
  • Brush Control
  • Dead/Diseased Tree Removal
  • Litter Control
/
  • Liner feet of slope failure per shoulder mile
  • Percentage of roadside area with noxious weeds
  • Average height of grass (inches)
  • Percentage of roadside area needing brush removal
  • Number of dead/diseased trees per shoulder mile
  • Number of fist-size objects per shoulder mile

Traffic Services /
  • Raised Pavement Markers
  • Signals
  • Signs—Regulatory and Warning
  • Signs—Other (including route signs, delineators, guideposts, and object markers)
  • Pavement Striping
/
  • Percentage of raised pavement markers defective
  • Percentage of traffic signals with lamps not working
  • Percentage of signs unreadable, severely damaged, or missing
  • Percentage of signs unreadable, severely damaged, or missing
  • Percentage of length worn or missing

Rest Areas /
  • Rest Areas
/
  • Condition rating (Janitorial services, Building and appurtenances and Landscape)

II.Data Collection Procedures

A.Field Sample Segments

Statistical methods will be used to identify randomly selected data sample sites along state highways. The sites are 0.10-mile segments (528 feet) selected in the 16,698 miles of roads (interstate and non-interstate) maintained by LADOTD. For non-interstate, divided highways, both directions of travel will be included in the sample. For Interstate routes, each direction of travel will be considered and sampled as a separate roadway. For a sample size that will give 95 percent confidence that the level-of-service average rating will be within 7 percent of the true value if the pass/fail rate is 80 percent for Interstate and 70 percent for non-Interstate, then the required sample size is 2,423 samples. The distribution of these samples by district is shown in Exhibit II1.

Exhibit II1: Field Sample Segments

District / Type / Miles / Samples / Total
2 / Interstate / 65.1 / 115 / 278
Other / 1071.2 / 163
3 / Interstate / 106.8 / 119 / 283
Other / 2325.0 / 164
4 / Interstate / 136.8 / 120 / 284
Other / 1933.0 / 164
5 / Interstate / 118.4 / 120 / 284
Other / 1955.8 / 164
7 / Interstate / 78.9 / 117 / 280
Other / 1180.6 / 163
8 / Interstate / 114.0 / 119 / 283
Other / 2492.1 / 164
58 / Interstate / 0.0 / 0 / 163
Other / 1423.2 / 163
61 / Interstate / 87.7 / 118 / 282
Other / 1741.1 / 164
62 / Interstate / 185.5 / 122 / 286
Other / 1682.6 / 164
Total / 16698.0 / 2423

A random number table will be used to generate random numbers to select sample sites. Then roads within a district can be assumed to be a single road. For example, non-Interstate roads in District 2 can be assumed to be a single 1071-mile road. The required number of samples will be obtained (163) from the random number tables with values between 0.0 and 1.0. By multiplying these numbers by the total number of miles in each district, the mileposts of the field sample segments will be obtained. For convenience, the roads in each district should be arrayed in numerical order, with each road length noted.

All identified features within each field sample segment will be evaluated. The survey is intended to assess the current condition that exists at the point in time when the evaluation takes place. In the future, two or more surveys per year should be conducted to account for seasonal variations.

B.Data Collection Equipment

The necessary equipment for completing field assessments is as follows:

  • Condition rating forms for recording data.
  • Measuring tape, ¾ inch to 1 inch wide by 25 feet long, graduated in both inches and feet.
  • Measuring wheel, with a capacity of at least 528 feet, for measuring distances longer than the length of the flexible tape.
  • Flashlight for looking inside of culverts, catch basins, and similar features.
  • Can of florescent spray paint for marking starting and ending mileposts of field sample segments.
  • Traffic cones (three minimum).
  • Flashing light on top of vehicle.
  • Long rod with hook for evaluating catch basins or manhole sumps. Lids may have to be pulled to accurately evaluate sumps.
  • Probe rod for locating bottom of culvert when obscured by sediment.
  • 3-foot straight-edge and ¾ inch shim for determining rut depth.
  • Florescent orange or green safety vest.
  • Protective clothing such as hat, field boots, jeans, and long-sleeved shirt.

C.Safety Responsibility

The survey teams shall conduct the work to ensure the least possible obstruction to traffic. During the data collection process, the team members shall provide for the safety and convenience of the public and residents along the roads and of the team. The team vehicle and team members must be properly outfitted with safety equipment.

If any unsafe roadway condition is observed, in or out of a field sample segment, the team will immediately notify the nearest maintenance crew by radio or telephone. The team will describe the problem and request that the appropriate shop respond. The team is not expected to perform maintenance while conducting the condition ratings. However, as a matter of courtesy to motorists, large items of debris should be removed from the roadway.

D.Data Collection Procedures

In every case, the primary concern of data collectors should be the safety of the team and of the road users. Following are the general procedures for collecting field data (maintenance condition assessment criteria and inspection procedures for individual maintenance features are presented in Appendix A):

  • Using intersections and the vehicle DMI, locate and mark the starting and ending mileposts for each field sample segment. These sample segments will be identified by spray paint at the edge of the shoulder so that they can be located again if needed. Placing a traffic cone on the starting and ending mileposts also may help identify the limits of the field sample segment.
  • If any portion of the field sample segment falls on a bridge, move the sample segment forward or backward as necessary to avoid the bridge. Note any adjustments in the comments on the data collection form.
  • Field sample segments falling within construction zones should not be evaluated. Relocate the sample segment outside of the construction area but as close to the original segment as possible. Note any adjustments on the data collection form.
  • All linear measurements should be rounded up to the nearest foot. Do not use fractions or increments less than one foot.
  • From the starting milepost, rate all identified features on one side of the roadway in the field sample segment. Return to the starting milepost and rate the other side from start to end. For safety reasons, walk in the direction facing traffic whenever possible. Distance measurements should be taken from the starting milepost of the field sample segment in the direction of increasing milepost numbers. The starting and ending mileposts of linear features located within the field sample segment should be measured as distance from the sample segment starting milepost.
  • Interstate highways will be rated only in the direction indicated in the random sample list.
  • If a feature is located in the middle of an interstate median, rate the feature only in the North and East directions to avoid double counting.
  • Non-interstate divided highways should be rated both directions, but only if it is possible and safe to rate both directions. Otherwise rate only one direction.
  • Pavement deficiencies are cumulative. For example, a 25 sq. ft. area of alligator cracking may contain 2 potholes. Count the 2 potholes independently from the alligator cracking.
  • To facilitate estimating area percentages, Appendix C presents diagrams of different percentages of deficient sample segments.
  • Input each day’s condition ratings into the Excel data condition file. This file provided a form that replicated the data collection form used on the filed.
  • E-mail the updated excel file to Ms. Ronda Foster at: .

la09702r05DataCollectionManual051213(5).docLADOTD
021018-12.03Level-of-Service Data Collection Manual

A-1

Appendix A: Road Maintenance Feature Inventory and Condition Rating: Data Collection Criteria

Following is a list of maintenance features and the exhibit number on which the assessment criterion and inspection procedures for each can be found:

Asphalt Pavement / Exhibit
Potholes / A-1
Rutting / A-2
Raveling / A-3
Alligator Cracking / A-4
Linear Cracking / A-5
Area Cracking / A-6
Sweeping / A-7
Other (bleeding, humps, sags, shoves, delamination, etc.) / A-8
Concrete Pavement
Potholes / A-9
Spalling / A-10
Longitudinal / Transverse Cracking / A-11
Longitudinal Faulting / A-12
Traverse Faulting / Bumps / A-13
Sweeping / A-14
Shoulders
High Shoulder / A-15
Edge Rutting / A-16
Drainage
Pipes and Culverts / A-17
Drop Inlets and Catch Basins / A-18
Ditches / A-19
Curb and Gutters / A-20
Roadside
Erosion Control / A-21
Noxious Weeds / A-22
Mowing / A-23
Brush Control / A-24
Dead / Diseased Tree Removal / A-25
Litter Control / A-26
Traffic Services
Raised Pavement Markers / A-27
Signals / A-28
Signs—Regulatory and Warning / A-29
Signs—Other (Including route markers, delineators, guideposts, and object markers) / A-30
Pavement Striping / A-31
Pavement Markings / A-32
Rest Areas
Rest Areas - Janitorial Services, Building and Appurtenances, and Landscape / A-33
Rest Areas Condition Rating / A-34

Exhibit A-1: Asphalt Pavement, Potholes

Maintenance Group: Asphalt Pavement / Date: January 2006
Maintenance Feature: Potholes
Definition:
Potholes are bowl-shaped voids or depressions in the pavement surface that are greater than 6 inches by 6 inches by 1 inch deep. Potholes are localized failure areas usually caused by weak base or subgrade layers.
Measurement Unit:
Number of potholes greater than 6 inches by 6 inches by 1 inch deep per lane mile.
Inspection Procedure:
Record the sample segment route, starting milepost, direction of travel, and number of lanes.
Inspect the paved surface within the field sample segment for potholes in all lanes of the road in the identified direction of travel.
Record the number of potholes and milepost.

Exhibit A-2: Asphalt Pavement, Rutting

Maintenance Group: Asphalt Pavement / Date: January 2006
Maintenance Feature: Rutting
Definition:
Ruts are defined as vertical deformations in the pavement surface along the wheel tracks that can hold ¾ inch or more of water. In severe cases, pavement uplift may occur along the sides of the rut, but in most instances, only a depression is noticeable. Rutting is caused by consolidation or lateral movement under traffic of any or all pavement layers, including subgrade. Rutting can cause water accumulation, which poses a hazardous condition.
Measurement Unit:
Linear feet of rutting per lane mile.
Inspection Procedure:
Record the sample segment route, starting milepost, direction of travel, and number of lanes.
Inspect the paved surface within the field sample segment for rutting. Measure the length of rutting that will cause water accumulation, using a straight-edge and ¾ inch shim.
Record the total length of rutting including all ruts in all lanes.

Exhibit A-3: Asphalt Pavement, Raveling

Maintenance Group: Asphalt Pavement / Date: January 2006
Maintenance Feature: Raveling
Definition:
Disintegration of the pavement from the surface downward due to the loss of aggregate particles. Raveling may occur as a result of asphalt binder aging, poor mixture quality, segregation, or insufficient compaction.
Measurement Unit:
Percentage of surface area distressed.
Inspection Procedure:
Record the sample segment route, starting milepost, direction of travel, and number of lanes.
Inspect the paved surface within the field sample segment for raveling.
Measure and record the area in all lanes with raveling.

Exhibit A-4: Asphalt Pavement, Alligator Cracking

Maintenance Group: Asphalt Pavement / Date: January 2006
Maintenance Feature: Alligator Cracking
Definition:
Alligator cracking are those cracks that divide the pavement into alligator skin shaped pieces. This feature presents base failure.
Measurement Unit:
Percentage of surface area distressed.
Inspection Procedure:
Record the sample segment route, starting milepost, direction of travel, and number of lanes.
Inspect the paved surface within the field sample segment for alligator cracking.
For each area within the sample segment with alligator cracking measure the length and the average width of the distressed surface. Record the total area in all lanes with alligator cracking.

Exhibit A-5: Asphalt Pavement, Linear Cracking

Maintenance Group: Asphalt Pavement / Date: January 2006
Maintenance Feature: Area Cracking
Definition:
All unsealed cracks at least ¼ inch wide running generally parallel or perpendicular to the centerline and edge-line striping.
Measurement Unit:
Linear feet of cracking.
Inspection Procedure:
Record the sample segment route, starting milepost, direction of travel, and number of lanes.
Inspect the paved surface within the field sample segment for cracks wider than ¼ inch. If there is significant presence (more than 25 percent of the area) of linear cracking in the sample segment, rate as area cracking.
Measure the length of cracking parallel and perpendicular to the centerline using a measuring tape or measuring wheel, as appropriate. Record the total length of cracking wider than ¼ inch in all lanes.

Exhibit A-6: Asphalt Pavement, Area Cracking

Maintenance Group: Asphalt Pavement / Date: January 2006
Maintenance Feature: Area Cracking
Definition:
Significant number of cracks at least ¼ inch wide running generally parallel or perpendicular to the centerline and edge-line striping other than alligator cracking. This feature does not present base failure.
Measurement Unit:
Percentage of surface area distressed.
Inspection Procedure:
Record the sample segment route, starting milepost, direction of travel, and number of lanes.
Inspect the paved surface within the field sample segment for cracks wider than ¼ inch. If the area within the sample segment is less than 25 percent of the paved area then rate as linear cracking.
For each area within the sample segment with area cracking, measure the length and the average width of the distressed surface. Record the total area of cracking wider than ¼ inch in all lanes.

Exhibit A-7: Asphalt Pavement, Sweeping