Site style | The natural fusion of Wirtgen WR 240 and the Xinjiang Kalajun grassland

Beautiful scenery needs to be carefully taken care of. The maintenance of scenic roads must take into account the impact of construction on the natural environment. The Wirtgen WR series of tire-type cold regenerative machines provide environmentally friendly, low-carbon and efficient road maintenance solutions for the scenic spot. The successful application experience of road maintenance in the beautiful grassland Kala Jun scenic area is worth learning.

The Karayu Grassland Scenic Area is located in the Tex County of the Ili River Valley in Xinjiang. It is the transitional zone between the Tianshan Mountains and the Ili River Valley. It is rich in precipitation, cool in climate, rich in soil and has hundreds of high-quality pastures. It was officially listed in 2013. UNESCO World Heritage List. The Kala Mountain in the Kala Jun grassland is an east-west mountain with two gullies and comb-like mountains. The mountains are undulating and growing, with dense original spruce forests. The Kala Jun Mountain stretches for 42 kilometers and is 25 kilometers wide. The altitude is between 2000-2800 meters and the total area is 1050 square kilometers. The scenery is very beautiful.

Long roads in the scenic area

The road in the scenic area is built on the black soil. The road width is 5 m. The structure is 4 cm AC-13 surface layer + 18 cm gravel stable base. The water content of the road bed is above 5%, and the snow area of ​​the winter road is more than 1 m. Some sections of the road are covered with snow all the year round, and the melting of snow in spring often causes the roadbed to be destroyed. The special geographical structure leads to the vertical and horizontal pavement, cracks and subsidence, and needs to be repaired every year.

With the increasing awareness of environmental protection in recent years, the extensive method of excavation and replacement in the past has become less and less suitable for the current situation. In the maintenance and construction of scenic roads, sand and cement need to be transported into the site from several hundred kilometers away. The abandoned materials can not be dumped. Therefore, it is necessary to complete the 3.5 km grassroots overhaul mission within 20 days. The traditional maintenance method is obviously not satisfactory. In 2019, experts from the Turks Transportation Bureau made a careful comparison and evaluation of various domestic maintenance methods to determine the use of Wirtgen cement in-situ cold recycling process for basic maintenance.

Damaged pavement in the scenic area

Low carbon environmental protection scenic road

In this construction, the 3.5 km road of the flower section of the East Karayu Scenic Area was selected for the cement cold reclaimed base test. The width of this section is 5~5.5 m, the width after regeneration is 6~6.5 m, and the regeneration depth is 18 cm. For special geographical structures, high-dose cement is used to regenerate the road base layer, and the strength of the base layer after regeneration is 2.5 Mpa or more.

The construction party first arranges the test section to determine the suitable milling speed and working speed of the WR 240. Check that the mixing grade is within the allowable range of the specification, and the mixture is evenly mixed without segregation; confirm that the optimum mixing water is 1.8%, using 22 t Single steel drum roller low frequency high amplitude vibration pressure 3 times, high frequency low amplitude vibration pressure 2 times, reaching 97% compaction requirement. The mountain roads are rugged and narrow, the climate is changeable, snowfall on the mountains, and rain under the mountains, which brings great difficulties to cement transportation and construction.

Mountain road covered by snow

Under extremely unfavorable climatic conditions, the construction side adjusts the process and operation time on site, adjusts the rolling process, and adopts measures such as covering health after the regeneration, to complete the entire road maintenance task ahead of time. After 7 days of curing, the core sample was drilled and the core sample was completely compact, which fully achieved the desired effect.

Beautiful landscape: Wirtgen WR 240 for efficient construction

As a mature maintenance technology, the cement on-site cold regeneration technology has been applied more and more widely, and its economic and rapid characteristics are becoming more and more obvious. Reduce environmental pollution while reducing maintenance costs. Practices in recent years have shown that by reasonably adjusting the proportion of materials in the reclaimed construction, reasonably selecting parameters and changing some of the processes, the service life of the pavement structure after regeneration is prolonged, and it can be applied well in areas with large annual temperature differences.

Recycled pavement

The cold reclaimed construction of the cement has greatly improved the traffic capacity and service level of the scenic roads, making the scenic spot more beautiful, allowing more people to enjoy the Kala Jun, appreciate Yili, appreciate Xinjiang, and appreciate the beautiful rivers and mountains of the motherland! (This article is from Wirtgen China)