Semi-Flexible Grouting Material

I. Product Introduction:

Semi-flexible pavement is based on a large-void asphalt mixture matrix. By infusing highly fluid cement slurry, it fully fills the voids between asphalt with appropriate fluidity, providing adequate strength and bonding. This allows the asphalt mixture and cement slurry to work together, forming a stable structure that combines rigidity and flexibility. This composite pavement improves resistance to rutting, cracking, oil erosion, and displacement, thereby enhancing comfort, safety, water stability, fatigue resistance, and high-temperature stability. It is widely used in heavy-duty roads, toll stations, gas stations, uphill sections, etc. The specialized grouting material used in semi-flexible pavement is called semi-flexible grouting material. It is precisely formulated from special high-quality cement, active fillers, and various high-performance additives.

II. Product Features:

1. Highly fluid, excellent pourability, high infusion rate, superior permeability, no vibration required after grouting.

2. Early strength, no shrinkage, no bleeding, no cracking.

3. High pavement stability. The Marshall stability of the mixed pavement after using semi-flexible grouting material is more than three times that before infusion, and the dynamic stability after 3 days of curing far exceeds that of ordinary asphalt mixtures.

4. High pavement strength. The void ratio of large-void asphalt pavement is as high as 20%-30%. Semi-flexible grouting material utilizes its high fluidity to fully fill the voids, with an infusion rate exceeding 80%, significantly reducing the overall porosity of the pavement. It also integrates the voids within the original structure, increasing density and load-bearing strength, making it less prone to rutting.

5. Convenient construction—simply mix with water and infuse. Early-strength and ultra-early-strength types can be customized as needed.

III. Construction Method

Semi-flexible pavement construction differs from ordinary asphalt pavement due to specific requirements and design methods. It mainly consists of two stages: laying the matrix asphalt mixture surface and infusing the grouting material.

1. Laying the Matrix Asphalt Mixture

Mixing, transporting, paving, and compacting the mixture.

2. Infusing the Grouting Material

Core drilling and sampling - determining porosity - determining grouting volume - preparing grouting slurry - infusing grouting material - surface treatment and cleaning - curing - opening to traffic.

IV. Construction Precautions:

1. The matrix asphalt mixture must be mixed uniformly. Strictly control the heating temperatures of asphalt and aggregates, and the discharge temperature of the mixture. The temperature upon arrival at the site should not be lower than 120°C.

2. The bottom and side plates of transport vehicles for the matrix mixture should be coated with a release agent or anti-sticking agent. During transportation, cover with tarpaulins to prevent heat loss, rain, and environmental pollution.

3. The paving process should be uniform, slow, and uninterrupted. Strictly control flatness. The paving speed should be determined based on paving thickness, width, and supporting machinery, generally controlled within the range of 2–6 m/min.

4. The compaction process for the matrix asphalt mixture, like ordinary asphalt mixtures, is divided into initial compaction, intermediate compaction, and final compaction. The specific compaction process is: initial compaction with a 12t steel-wheel roller for one pass; intermediate compaction with static pressure for 1–2 passes; final compaction with a <7t steel-wheel roller for finishing. The compaction degree should be controlled between 95%–100%.

5. When mixing the grouting material, the mixing equipment speed should not be lower than 1000 r/min. Strictly adhere to the water dosage required by the product. Grouting can only be performed when the temperature of the matrix asphalt mixture drops below 40°C. Spread the mixed grouting material on the surface of the porous matrix asphalt mixture, and repeatedly drag with a rubber rake to allow natural penetration. If necessary, use a small vibrator to assist penetration. Finally, clean the residual slurry from the surface with a rake to expose the asphalt mixture, ensuring the凹凸性 (unevenness) of the aggregate surface and increasing pavement skid resistance. 

6. When the construction temperature is below 30°C, no special curing method is needed; simply cure at normal temperature for 2–3 days. When the construction temperature is above 30°C, cover with plastic film for curing. If the grouting material is of the early-strength type, traffic can be opened after a few hours of curing once the mortar hardens.