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Generation and propagation of reflective cracking and thermal cracking of asphalt pavement in cold regions of China
Published in Inge Hoff, Helge Mork, Rabbira Saba, Eleventh International Conference on the Bearing Capacity of Roads, Railways and Airfields, Volume 1, 2021
W.Y. Zhou, Z.G. Chen, Z.N. Chen, W.J. Qin, J.Y. Yi*
The embedded process of optical fibre sensors in the bottom layer and the middle layer was similar to these procedures, as shown in Figure 3. After measurement and marking, the no compaction asphalt mixture layer was smashed into large blocks of mixed stone and transferred manually. Similarly, a depth of 5 cm and width of 5 cm groove was formed. As soon as the straightened optical fibre sensors were put into the groove, the groove would be buried manually with the remaining asphalt mixture to avoid destruction of the optical fibre sensors due to the vibration of the road roller.
Rising to the challenge of managing bridges in Australia
Published in Hiroshi Yokota, Dan M. Frangopol, Bridge Maintenance, Safety, Management, Life-Cycle Sustainability and Innovations, 2021
Before 1900, standards for bridge design and loading did not exist. Many were built to withstand the loads from horse and cart and may have been tested using a 16 ton road roller. Some of these bridges are still in service today.
McAdam invents a major new pavement using broken stones
Published in Maxwell Lay, John Metcalf, Kieran Sharp, Paving Our Ways, 2020
Maxwell Lay, Metcalf John, Sharp Kieran
There was a limit to the weight of roller that a horse could pull, and it was evident that that weight was insufficient to properly finish a macadam pavement.346 A further problem with horse-drawn rollers was that the horses’ hooves often damaged the pavement surface as the horses struggled find sufficient purchase to draw the heavy rollers. However, the need for change was driven mainly by the growing use of asphalt paving, to be discussed in Chapter 13, and steam-powered road vehicles were becoming common in the 1840s.347 The French began using steam-powered rollers in about 1850 during trials of asphalt on the Avenue de Marigny in Paris. The device was probably designed and built by Louis Lemoine of Bordeaux who took out a patent in 1859 and used his machine in Bordeaux and in the Bois de Boulogne in Paris.348 The Paris Steam Road Rolling Company then produced a steam roller patented by M Ballaison which was also used in Paris in 1862. The Paris municipality conducted comparative trial of horse-drawn and steam-powered rollers. This led, in 1865, to the municipality giving a 6-year contract to the Paris Steam Road Rolling Company to provide seven steam rollers for the continuous use of the municipality.349 A French road roller that could be drawn by horse or steam-power is shown in Figure 9.7. The use of rolling increased dramatically following the introduction of steam-powered rollers.
Investigation on the compaction process of steel bridge deck pavement based on DEM-FEM coupling model
Published in International Journal of Pavement Engineering, 2023
Gang Liu, Zhendong Qian, Xiaoyun Wu, Leilei Chen, Yang Liu
Figure 7 shows that the single settlement reached the maximum and gradually decreased with the rolling repetitions. The cumulative settlement showed an upward trend and stayed stable after 7 rolling repetitions. The single settlements of the first and second rolling repetition were relatively large. The asphalt mixture particles were levelled and stabilised under the load of the road roller, and the gap between particles was greatly reduced. This stage can be considered the initial compaction stage. During the 3rd to 5th rolling repetition, the single settlement was significantly reduced. The asphalt mixture particles continued to move under the compaction load, and further filled the voids to form a dense structure basically. This process can be considered the recompaction stage. After the 7th rolling, there was nearly no single settlement and the accumulated settlement reached 3.4 mm. To prevent excessive compaction, the 6th to 7th rolling repetition was regarded as the final compaction stage.
Investigation on mixture recovery properties in fatigue tests
Published in Road Materials and Pavement Design, 2018
Ivan Isailović, Michael P. Wistuba, Augusto Cannone Falchetto
Test specimens were cut from slabs (50 × 70 × 4 cm³) made using the segmented steel roller compaction method (see Figure 2). Using the standard compaction procedure it is possible to produce HMA slabs with nearly the same characteristics (air voids distribution, particle distribution, particle orientation and performance properties) compared to those in the field (Renken, 2000). The compactor uses a steel roller cylindrical sector to produce a kneading action and downward force to the specimen in both pre-compaction and main compaction phases (see Wistuba, 2014). The pre-compaction phase is displacement controlled and is intended to simulate the compaction effort of the road paver. The main compaction phase is assumed to simulate the compaction by the road roller and consists of 12 roller passes in stress control.
Evaluating asphalt pavement surface texture using 3D digital imaging
Published in International Journal of Pavement Engineering, 2020
Mixture specimens were compacted in a laboratory using a small road roller, as shown in Figure 14, which can provide 300 N/cm line compressive stress according to the national standard of China (JTG E20 2011-T0703, 2011). After being mixed, the mixtures were conditioned at 135°C in oven for 2 h. Meanwhile, the moulds were kept at 135°C in oven for 2 h. After being poured into the mould, the mixture sample was compacted by a small road roller.