Special Scenarios

I. Mountain road solutions

Core Difficulties: Highly undulating terrain, unstable geology, drainage difficulties, restricted sight distance.

● Engineering design:

- Spreading technology: adopt “zigzag” or spiral tunnel to reduce the slope (slope ≤ 8%), such as the spiral spreading design of Yaxi Expressway Ganhaizi Special Bridge;

- Anti-slip road surface: steep slope section paved with steel slag aggregate anti-slip layer, friction coefficient ≥ 0.7;

- Protection engineering: active protection net (intercepting falling rocks) + anti-slip piles (managing landslides) + arch skeleton slope protection (consolidating soil and preventing scouring).

● Safety facilities:

- Setting up convex mirrors and linear guide markers at sharp bends;

- The end of the long downhill to add a hedge lane (sand pile buffer + forced speed bumps).

Second, ice and snow area road solutions

Core difficulties: low-temperature freezing and thawing, snow and ice, road surface damage.

● Material and structure:

- Cold-resistant asphalt: add rubber powder modifier, low-temperature cracking temperature down to - 30 ℃;

- Pervious concrete base: accelerates snow melting and drainage, and prevents the road surface from freezing and expanding.

● Intelligent snow removal technology:

- Active snow-melting system: the road surface is embedded with heating cable or conductive concrete, which automatically senses icing and starts heating;

- Intelligent spreading vehicle: GPS positioning linkage, automatically adjusting the amount of snowmelt sprayed according to the thickness of snow.

Third, heavy traffic road solutions

Core difficulties: the road structure is easy to fatigue, rutting and potholes are frequent.

● Enhanced design:

- Multi-layer composite grass-roots level: cement stabilized gravel (20cm) + graded gravel (15cm) + asphalt stabilized gravel (10cm), total thickness ≥45cm;

- Steel fiber concrete surface layer: 50% improvement in fatigue resistance, suitable for port and mining roads.

● Monitoring and maintenance:

- Deploying load cell (WIM) to monitor overloaded vehicles in real time;

- High-frequency radar detection, early detection of roadbed de-voiding potential hazards.

Fourth, the city's old road reconstruction program

Core difficulties: complex underground pipelines, construction nuisance, limited space.

● Minimally invasive construction:

- Non-excavation technology: directional drilling through (laying new pipelines), pipe lining repair (old pipe renovation);

- Thin-layer overlay: milling 2-3cm of old surface layer and paving SMA, reducing noise by 5dB and shortening construction period by 60%.

● Functional upgrade:

- Functional upgrading: additional sponge facilities (permeable paving + sunken green areas);

- Optimize the slow-moving system, and physically separate the non-motorized road from the motorized road.

V. Ecologically Sensitive Area Road Solutions

Core difficulty: Minimize ecological damage and protect biological habitats.

● Eco-friendly design:

- Eco-trestle bridge: such as the wildlife corridor of the Qinghai-Tibet Railway, adopting overhead design to reduce the blockage of migration routes;

- Biomimetic materials: Slopes are covered with rock-like textured concrete and sprayed with a growth substrate that can hold plant seeds.

● Construction control:

- Temporary right-of-way adopts recyclable steel trestle, and native vegetation is restored after completion;

- Wastewater is discharged after treatment in a three-stage sedimentation tank, and the removal rate of suspended solids is ≥95%.

Sixth, tourist attractions road solutions

Core difficulties: the need to take into account the landscape, safety and experience.

● Characteristic design:

- Colorful road surface: spray fluorescent paint (luminous at night) on the bicycle path, and pave imitation wood grain concrete on the scenic road section;

- Intelligent guide: AR logo embedded in the road surface, scanning code can get the explanation of attractions.

● Safety and Service:

- A “meeting warning radar” is set up at sharp bends, broadcasting real-time information about oncoming traffic;

- Eco-stations (including charging piles, resting pavilions and barrier-free facilities) are set up every 1 kilometer.

Innovative Trends and Cases

- Photovoltaic road: Pave light-transmitting photovoltaic panels in scenic spots or service areas, with annual power generation meeting lighting demand;

- Self-repairing roads: embedded with microencapsulated materials that release repair agents when cracks are triggered;

- Case: Norway's Atlantic Road, using S-shaped route design to enhance the landscape level, supporting the windbreak guardrail and viewing platform, becoming a net-famous place to visit.

Road solutions for special scenarios need to deeply integrate engineering technology, environmental science and scenario requirements to achieve a balance of function, safety and ecology through customized design.