CN-122013648-A - Construction system and process for flowable cement asphalt mixture

CN122013648ACN 122013648 ACN122013648 ACN 122013648ACN-122013648-A

Abstract

The invention discloses a construction system and a construction process of a flowing cement asphalt mixture, wherein the system comprises a mixing unit, a transportation unit and a conveying unit, wherein the mixing temperature T is determined by an equal viscosity temperature corresponding to the cement viscosity of 0.5 Pa.s, the transportation unit comprises a box body and a cylinder body which divides the box body into a heating medium chamber and a storage chamber, the storage chamber is provided with a feed inlet, a discharge outlet and a rotatable discharging device, the storage chamber is internally provided with a turning device and a conveying device, a heating element and a first temperature sensor are arranged in the heating medium chamber, a second temperature sensor is arranged in the storage chamber, the operation unit is matched with the discharging device, the initial pressure temperature T-10-T+10 ℃ of the rolling unit is higher than or equal to T-20 ℃. The process comprises the steps of mixing, transporting, operating and rolling. The invention solves the segregation and accumulation problems caused by high fluidity of FMA mucilage through accurate temperature control, continuous stirring, rotatable unloading and high Wen Nianya, realizes the molding of a skeleton-super-compact structure, and improves the pavement quality and service life.

Inventors

WU KUANGHUAI
LI HANMEI
ZHENG YUQI
CAI XU
HUANG JIANDONG
HUANG WENKE
WANG CHENGYU

Assignees

广州大学

Dates

Publication Date: 20260512
Application Date: 20260327

Claims (10)

1. A flowable cement asphalt mixture construction system, comprising: the mixing unit is used for preparing coarse and fine aggregates, asphalt and filler according to the grading curve and the composition parameters of the flowing cement asphalt mixture, and the mixing temperature T DEG C of the mixing unit is determined by the equal viscosity temperature corresponding to the cement viscosity of 0.5Pa & s; The transportation unit comprises a moving device and a box body arranged at the upper part of the moving device, wherein a cylinder body is arranged in the box body and divides the space in the box body into a heat medium chamber and a storage chamber; The upper part of the storage chamber is provided with a feed inlet, the rear end wall of the storage chamber is provided with a discharge outlet, and the discharge outlet is provided with a rotatable discharge device; The storage chamber is internally provided with a turning device and a conveying device which are arranged up and down, the turning device is used for keeping a uniform slurry coating state of the flowing mucilage asphalt mixture, and the conveying device is used for conveying the flowing mucilage asphalt mixture to the discharge port; The heating medium chamber is provided with a medium inlet and a medium outlet, a heating element and a first temperature sensor are arranged in the heating medium chamber, a second temperature sensor is arranged in the storage chamber, and the heating element, the first temperature sensor and the second temperature sensor are used for controlling the temperature of the mixture within a range of T-10-T+10 ℃ in the transportation process; the operation unit is matched and connected with the unloading device of the transportation unit and is used for receiving the flowing cement asphalt mixture and performing paving or repairing operation; And the rolling unit is used for rolling the asphalt mixture of the fluid cement after the paving or repairing is finished, the initial pressure temperature of the rolling unit is controlled to be T-10-T+10 ℃, and the re-pressure temperature is more than or equal to T-20 ℃.
2. The construction system according to claim 1, wherein the turning device includes a pair of rotation shafts extending in a length direction of the storage chamber, both ends of the rotation shafts being rotatably provided at both ends of the storage chamber, an outer wall of the rotation shafts being provided with a plurality of turning blades in a length direction thereof; the conveying device is a screw conveyer, and the screw conveyer comprises a main shaft and screw blades fixed on the main shaft, wherein the main shaft is supported on the end wall of the lower part of the storage chamber, one end of the main shaft is provided with a power input piece, and the other end of the main shaft extends to the discharge hole.
3. The construction system according to claim 1, wherein the discharge device comprises a discharge valve provided at the discharge port, a base fixed at the upper part of the moving device, a rotating column rotatably provided on the base, and a sloping plate provided at the upper end of the rotating column, the discharge valve being used for controlling discharge of the flowable cement asphalt mixture, the sloping plate being located below the discharge port for receiving and guiding the discharged mixture, wherein the rotating column is capable of driving the sloping plate to rotate between a storage position and an extended position.
4. The construction system according to claim 1, wherein the working unit is a paving device, the paving device comprises a frame, a screw distributor arranged at the front side of the frame, and a screed plate arranged at the rear side of the frame, the screw distributor is matched with the discharging device and is used for receiving the flowable cement asphalt mixture, and the screed plate is used for vibrating and leveling the paved flowable cement asphalt mixture.
5. The construction system according to claim 1, wherein the transportation unit further comprises a controller disposed on the moving device, the controller being electrically connected to the first temperature sensor, the second temperature sensor, the heating element, the flipping device, and the conveying device, respectively.
6. The construction system according to claim 1, wherein the compaction unit comprises a steel-wheel vibratory roller and a rubber-wheel roller, the compaction unit being configured to first perform compaction with the steel-wheel vibratory roller and then perform compaction with the rubber-wheel roller.
7. A flowable cement asphalt mixture construction process using the construction system according to any one of claims 1 to 6, comprising the steps of: Mixing procedure, namely preparing coarse and fine aggregates, asphalt and filler by adopting the mixing unit according to the grading curve of the flowing cement asphalt mixture, dry-mixing for 30-45 s, wet-mixing for 10-15 s, wherein the mixing temperature T is determined by the equal viscosity temperature corresponding to the cement viscosity of 0.5 Pa.s; a transportation procedure, wherein the transportation unit is used for transporting the flowing mucilage asphalt mixture, the temperature is detected by the first temperature sensor and the second temperature sensor in the transportation process, the heating element is controlled by the controller, the temperature of the flowing mucilage asphalt mixture is controlled within the range of T-10 to T+10 ℃, the heat preservation transportation time is less than or equal to 180 minutes, the stirring device is used for keeping continuous stirring in the transportation process, and the flowing mucilage asphalt mixture is conveyed to the discharge port by the conveying device; A working procedure, namely discharging the flowing cement asphalt mixture in the transportation unit to the working unit through the discharging device for paving or repairing operation; and a rolling procedure, namely immediately adopting the rolling unit to roll after the paving or repairing is finished, controlling the initial pressure temperature to be T-10-T+10 ℃, and rolling the framework until the framework is stably formed, wherein the re-pressing temperature is more than or equal to T-20 ℃.
8. The construction process according to claim 7, wherein in the rolling step, rolling is performed by using a steel-wheel belt vibratory roller and then rolling is performed by using a rubber-wheel roller.
9. The construction process according to claim 7, wherein the construction thickness of the flowable cement asphalt mixture for single paving and rolling is 2-20 cm.
10. The construction process according to claim 7, further comprising a detection step of detecting fluidity of the flowable cement asphalt mixture by a mixture screening method and quantitatively sampling an oil-stone ratio by a combustion test.

Description

Construction system and process for flowable cement asphalt mixture Technical Field The invention relates to the technical field of pavement construction, in particular to a construction system and a construction process of a flowable cement asphalt mixture. Background For over four decades, china has realized the development of crossing type highway infrastructures. By the end of 2024, the total mileage of national roads breaks through 549.04 ten thousand kilometers, wherein the expressway network stably occupies the first place of the world, reaching 19.07 ten thousand kilometers. In the technical category of asphalt pavement, china has constructed a modified asphalt technical system with independent intellectual property rights, and has made obvious progress in the aspects of mixture design theory, structural analysis method and the like. However, the industrial statistics data show that 60% of expressways in China need major repair after 10-12 years and 17% of expressways need major repair after 6-8 years, and the situation highlights the core technical problem of insufficient durability of the current asphalt pavement. The problem not only causes high service life cycle cost of the asphalt pavement, but also causes interference to driving due to frequent maintenance, reduces traffic capacity and service level of the road, and brings great pressure to pavement material resources and environment. The following root is traced, the current hot-mix asphalt (HMA) system takes mucilage sticky (without leakage) as a theoretical foundation stone, long-term dominant research and development directions of the mucilage sticky (without leakage) are adopted, asphalt mixture material optimization and durability improvement space is limited, and the current HMA design method all follows the requirement to meet the construction process. Because of the characteristic of HMA that the adhesive cement is sticky (without leakage), the construction process adopts a common material transporting vehicle to transport, the adhesive cement is not leaked in the transportation process, the temperature loss of about 20 ℃ can be allowed in the transportation and paving processes, and the rolling forming generally adopts a combined mode of a light steel wheel road roller (initial pressure), a heavy steel wheel road roller (back pressure), a heavy tyre road roller (optional) and a light steel wheel road roller (final pressure). Based on the common characteristic of 'sticky (no leakage) of the adhesive cement', the conflict exists among various performances of the HMA, so that the consumption of asphalt is difficult to increase, and measures for improving the gradation are limited, so that the research on the HMA is concentrated on the performances and the modification of asphalt binders for a long time. Meanwhile, in order to ensure the rut resistance, a larger void ratio (usually 4%) is required to be designed, and the local void ratio can reach more than 6% -8% due to insufficient segregation and compactness and the like. The factors cause that the overall performance of the HMA is difficult to fully improve, the performance cannot be considered, and the problems of construction segregation and the like, which cause early diseases of the pavement and limit the improvement of the durability of the HMA pavement. The prior art has proposed a flowable cement asphalt mix (Fluid MASTIC ASPHALT, FMA) theory and design method. The flowing cement asphalt mixture is a framework-super-compact asphalt mixture with the internal void ratio close to zero, which is formed by filling the framework gaps with the cement with large fluidity by means of technical measures such as self-flowing or vibration-assisted compaction. In the construction process, because the mucilage flows, the FMA can improve the asphalt dosage and greatly adjust the asphalt dosage on the basis of having anti-rutting performance, and a framework-super-compact structure with zero void ratio inside is formed. The structure is favorable for solving the problems of water damage, fatigue cracking, reflection cracking, aging, surface skid resistance, durability and the like, and is expected to realize the improvement of the service life of the asphalt pavement. Compared with the adhesive cement which is required by the prior HMA system, the adhesive cement has enough fluidity in the paving and rolling construction process. If the existing HMA construction technology is adopted, the FMA can have a bleeding phenomenon, so that segregation is uneven. In addition, the temperature is reduced in the transportation process, so that the mobility of the adhesive cement is insufficient in rolling construction, zero clearance cannot be realized, and even the problems of insufficient rut resistance and the like occur. Therefore, how to develop a construction system and process for adapting to the material characteristics of flowable cement asphalt mixture (FMA) is an urgent problem to be solved a