How to choose rollers for different roadbeds?

How to choose rollers for different roadbeds?

Summary

How to choose rollers to compact roadbeds? We will help you analyze how to choose different types of rollers to compact roadbeds from multiple angles. You will have the answer after reading.

How to choose rollers for different roadbeds?
How to choose rollers to compact roadbeds? We will help you analyze how to choose different types of rollers to compact roadbeds from multiple angles. You will have the answer after reading.

1. Use static smooth rollers to roll roadbeds

It is only suitable for compacting thin fill roadbeds. This is because the contact area between the rollers of static smooth rollers and the soil is large, the unit pressure is small, and the compaction capacity gradually decreases from the surface to the bottom, making the upper layer denser than the lower layer, and the overall density of the roadbed is poor. When compacting with static smooth rollers, the method of "thin filling, slow driving, and multiple times" should be adopted, that is, the thickness of the fill layer is thin (about 25~30cm), the rolling speed is slow at first and then fast, and the rolling is light first and then rolling. Tests show that when rolling with a static smooth roller, the density of the soil decreases with the increase of the filler thickness, and increases with the roller's own weight and the number of rolling times; but when the number of rolling times exceeds 8 times, the density does not increase much or at all, so it should be noted that the economically reasonable number of compaction times should be selected, generally not exceeding 8 times.

Road roller 01
Road roller 02

2. Rolling the roadbed with a tire roller

It is suitable for compacting various soils, and has the best compaction effect on relatively wet clay, and the effective rolling depth can reach more than 30cm. The biggest feature of the tire roller is that it can change the tire internal pressure according to the soil conditions, and control the maximum stress acting on the soil within the ultimate strength of the soil; another feature is that the pneumatic tire can be deformed, so that the compaction depth of the soil is kept within a certain depth range; third, the tire has a large contact area with the soil, the pressure is evenly distributed, the soil is compressed for a long time, and the compaction density is good.

Road roller 03

3. Compacting the roadbed with a vibratory roller

1. When rolling the fill roadbed, vibratory rollers of different tonnages should be selected according to the thickness of the fill, and the driving speed of the roller should also be noted. Generally, the compaction effect is proportional to the number of rolling times and inversely proportional to the driving speed; relevant tests show that the compaction effect is best when the driving speed is 3~6km/h.
2. When rolling gravel and other non-depressed roadbeds, high-frequency, low-amplitude vibratory rollers can be used, with a rolling speed of 3~6km/h and 2~3 rolling times. If the layer thickness is too thick, the rolling speed can be reduced.
3. When rolling non-plastic silt roadbed, the layer thickness can reach 0.7~1.0m, and a heavy roller of 10~15t can be selected
4. When rolling clay roadbed containing a certain amount of clay, a vibratory roller with medium or low static pressure can be selected
5. When rolling clay roadbed, a large-tonnage vibratory roller should be selected; when rolling high-strength clay roadbed, a sheep's foot vibratory roller must be used; when rolling clay roadbed, a high-amplitude, low-frequency compaction method should be used, and the compaction speed is 3~4km/h.