Question

presentation in Pavement

*You are required to prepare a short presentation (not more than 12 slides) in power point format regarding the subject that will be assigned to you. The subject is related to pavement distresses in flexible and rigid pavements.

*Every student will be required to collect comprehensive information about the distresses assigned to him (see the table in the next page). The information should include, but not limited to, distresses definition, causes, severity levels, measurement method, maintenance procedures and preventive measures.

*Your presentation should include the above items supported by figures, schematics, or any clarifying tools

*You are required to use at least 3 references for you work (books, journals, or internet). In order not to violate copy rights and plagiarism rules all resources and references should be listed in the last slide.

*Comprehensiveness, clearness and neatness of the content are key elements in the evaluation

* MY topic is (Lane to shoulder drop off + separation in rigid pavements ) *

Answer 1

Lane to shoulder drop off

Definition: It is the difference between height of lane and the height of adjacent shoulder. It occurs mostly due to the settlement of shoulder.

Caused by: Incomplete highway construction/reconstruction.

When road is resurfaced without providing adequate raise in the height of the shoulder.

Rutting caused by vehicle tires in unpaved roads.

Severity levels: Not applicable. Severity levels can be defined by categorizing the measurements taken, which is more desirable, because it is more accurate and repeatable than severity levels.

Measurment method: Measure at the longitudinal construction joint between the lane edge and the shoulder.

Record to the nearest millimeter at 15.25-m intervals along the lane-to-shoulder joint.

If the traveled surface is lower than the shoulder, record as a negative value.

Unit of measurement: millimeters.

Maintenence procedure: Providing safety edge.

Preventive measures: Drop off differential should be less than 2 inches.

Lane to shoulder separation

Definition: Widening of the joint between the edge of the lane and the shoulder.

Caused by: Poor quality tie bar installations.

Improper tie bar/transverse steel design.

Unstable base or subgrade volume changes.

Severity levels: Not applicable. Severity levels can be defined by categorizing the measurements taken, which is more desirable, because it is more accurate and repeatable than severity levels.

Unit of measurement: millimeters.

Measurment method: Record to the nearest millimeter at intervals of 15.25 m along the lane-to-shoulder joint.

Indicate whether the joint is well-sealed at each location.

Maintenence procedure: Cross stitching and Slot stitching.

Preventive measures: Proper design and construction of tie bars.