Gorski Consulting tested the old surface of the northbound Red Hill Valley Parkway in Hamilton, Ontario and then re-tested the surface after it was re-paved. This article discusses some of the differences.
The table below shows the data from the old surface that was obtained from testing on May 15, 2019. This was just before the roadway was shut down in preparation for re-paving.
The table below shows the data from the newly, re-paved, northbound surface from testing obtained June 16, 2019. This was at a time when the southbound lanes were still to be re-paved.
Comparing the two tables it can be noted that the reported testing commenced at an “earlier” location (i.e. further westward) in the May 15th testing on the old surface. The first row of the May 15th data shows a portion of the 30 seconds of travel where the first 21.5 seconds were obtained from west of the Pritchard Road overpass. This portion of the surface produced the highest motion of the test vehicle (Lateral Rotation = 0.0309, Longitudinal Rotation = 0.0190). In contrast the data from June 16th (on the newly paved surface) begins after passing the Pritchard Road overpass and the first data is from 10 seconds west of the Mud Street overpass. This difference in starting points was part of the reason why there was such a difference in the “Overall” averages of motion. While we are not aware of the specific boundary where the Lincoln Alexander Parkway becomes defined as the Red Hill Valley Parkway, the larger vehicle motions caused on the surface west of Pritchard are more consistent with the higher motions obtained throughout the Lincoln Alexander Parkway.
Comparisons can begin to be made when the test vehicle approaches the Mud Street overpass. In the table of the old surface data, the second row indicates that the road segment begins at 5.65 seconds before reaching the Mud Street overpass. At a speed of 86 km/h (23.9 metres per second) this means that the reported segment started at 135 metres west of Mud Street. In contrast the road segment in the first row of the table from the re-paved surface began at 10.0 seconds prior to reaching the Mud Street overpass. At an average of 88 km/h (24.4 metres per second) this means that we started documenting the data at about 244 metres prior to reaching the Mud Street overpass. So, this means that the documenting of the data from the re-paved surface began about 109 metres earlier. In other words, the second row of data of the old surface is comparable to the first row of data of the re-paved surface, except that the new data was started about 109 metres further west (i.e. “earlier”).
When we look at those two road segments starting west of Mud Street, we can note following vehicle motions:
Old Surface: Lateral Rotation = 0.0290, Longitudinal Rotation = 0.0116
New Surface: Lateral Rotation = 0.0129, Longitudinal Rotation = 0.0093
So there is a reduced level of motion of the test vehicle on the re-paved surface, particularly in the lateral motion.
The old surface data shows that the next seven road segments (i.e. next 7 rows of data) are illustrated in a green colour meaning that they are below 0.0200 radians per second. So this means that the surfaces of the road segments are in good condition. The distance over these seven road segments goes from 582 metres north of Mud Street to 765 metres north of Queenston Road. Taking the average of all these seven road segments gives us the following average: Lateral Rotation = 0.0152, Longitudinal Rotation = 0.0127.
In comparison we can look at the seven road segments from the table of re-paved surfaces: from 489 metres north of Mud Street to 892 metres north of Queenston Road. Taking the average of all seven road road segments gives us the following: Lateral Rotation = 0.0133, Longitudinal Rotation = 0.0101.
Comparing the differences in these averages shows that there has been an improvement, as expected, in the surface of the Red Hill Valley Parkway, after the re-paving was completed. Yet, the quality of the surface before the re-paving was “not bad”, or well below the 0.0200 threshold.
We can make a further comparison of the Red Hill Valley data to the data that we obtained on May 5, 2019 on the westbound Highway 401 from Wonderland Road to Tilbury, Ontario. This data was reported in a news article of May 29, 2019 entitled “Additional Road Data From Westbound Highway 401 Testing”. The overall average of the Highway 401 data was: Lateral Rotation = 0.0126, Longitudinal Rotation = 0.0096. We would consider this data as the “gold standard” for road surfaces because there is no other road data that we have collected which produced lower test-vehicle motions at highway speeds.
We can see that the re-paved Red Hill Valley road segments are not far behind the quality of the Highway 401 data. The lateral rotation on the Red Hill Valley was 0.0133 versus Highway 401 which was 0.0126. And for the Longitudinal rotation the Red Hill Valley was 0.0101 while Highway 401 was 0.0096. All these values are well below the 0.0200 threshold for what we defined to be a “good” road surface. Furthermore, the old surface of the Red Hill Valley was of lower quality but certainly well below the 0.0200 threshold and much lower than the results obtained from testing along the Lincoln Alexander Parkway.