13-05-2011, 12:13 PM
PRESENTED BY
A.RAJESH
SURFACE CONDITION TEST.ppt (Size: 145.5 KB / Downloads: 106)
SURFACE CONDITION TEST
INTRODUCTION
Evaluation of pavement is very essential to know the condition of pavement.
Surveys (OR) Tests are two types
(1) Evaluation survey
(2) Surface condition survey
Evaluation survey
Evaluation surveys are carried out to determine the structural adequacy of a pavement and to find out the reason for the condition of the pavement.
Surface condition test
Surface condition tests are made to determine the condition of the pavement
at any given time.
Surface condition tests are used in setting
up needs studies, priority ratings and maintenance programmes.
It does not evaluate the structural strength of pavement.
And it also no attempt is made to find out the reason for the pavement condition.
Surface condition tests
Roughness
Present serviceability index
Skid resistance
Benkelman beam deflection technique
Roughness
Pavement roughness is generally defined as an expression of irregularities in the pavement surface that adversely affect the ride quality of a vehicle
Roughness is an important pavement characteristic because it affects not only ride quality but also vehicle delay costs, fuel consumption and maintenance costs
NEED FOR ROUGHNESS MEASURMENT
Roughness of a road is a major determinant of the safety, cost, comfort and speed of travel
To assess maintenance needs
To assess quality of construction
For research purposes
Road roughness can be broadly classified into two categories
(1)Longitudinal distortion
(2)Transverse distortion
MEASUREMENT OF ROAD ROUGHNESS
Direct measurement of the longitudinal profile
Response type instrument method
Present serviceability index(PSI)
PSR is defined as "The judgment of an observer as to the current ability of a pavement to serve the traffic it is meant to serve" (Highway Research Board, 1962).
Present serviceability index(PSI)
A group of individuals drive over the pavement and rate the pavement on a scale.
The raters mark on the scale, which varies from 0 to 5.