What is the construction process of the chopped basalt fiber and basalt fiber composite ribs for road use, and what technical support and services can the manufacturer provide?
Construction guide plan for chopped basalt fiber reinforced asphalt concrete pavement
01.Proportional design and mixing
The grading of the ore material of the asphalt mixture should meet the requirements of the control range of the production mix ratio, and the amount of the mixture asphalt should be controlled at the production ratio of ±0.2%.
The basalt fiber can be added by manual feeding or automatic fiber feeding machine. It can be mixed into the mixing pot with the hot aggregate of the mixer. The mixing time should be extended appropriately. The dry mixing time is not less than 10s after adding basalt-fibers.
The mixing time of the asphalt mixture is determined according to the specific conditions, and the aggregate is uniformly coated with the asphalt. The production cycle of each batch mixer should not be less than 50~60s.
02 Transportation and paving
When loading the material from the storage bin to the transport vehicle, it is necessary to shorten the distance from the discharge port of the storage bin to the car panel and discharge the materials separately at different positions of the car.
First, parts of the materials are placed at the rear of the car, and then parts of the materials are placed at the front of the car, and then parts of the materials are placed in the middle of the car.
The paver that performs the work must have a device that automatically adjusts the thickness and leveling, and must possess a preliminary compaction device such as a vibrating screed or vibrating jaw. A mobile automatic leveling reference device should be used.
In order to improve the flatness and reduce the segregation of the mixture, the paver must be paved slowly, evenly and continuously without interruption. It is not allowed to change the speed or stop in the middle.
The ordinary section is paved by two paver echelons with a spacing of 5~8m. The spread width of the paving machines of the two pavers is not less than 20cm.
(1) The initial rolling should be carried out by using two double-wheel road rollers in a segmentation mode for 1~2 times, and rolling back and forth is counted as one pass;
(2) In order to compact the surface as soon as possible and reduce heat loss, the length of the segment should not exceed 30m;
(3) When the initial rolling is applied, the vibration static pressure is turned off for the first time, and turn on the vibration when it comes back, and the vibration compaction is performed to improve the compactness of the mixture rolling;
(4) The static pressure of the steel drum roller should not be lower than 12t, the vibration frequency should be 35~50Hz, and the amplitude should be 0.3~0.8mm. The high frequency and low amplitude are adopted to prevent the aggregate from being broken, and the specific rolling time is determined according to the test section data.
(1) The recompression phase is to compact the compactness of the basalt fiber asphalt layer to a predetermined standard value. It is advisable to use two tire rollers for recompression for 3 to 4 times. The specific data is determined according to the test section.
(2) Before the roller crush on the road, the tire should be cleaned and wiped with a mixture of water and kerosene (or diesel) (a ratio of 1:1). At the same time, each tire roller follows a worker, who should wipe the tires with the mixed liquid to prevent sticking from time to time.
01.Mixed ratio design & mixing
According to different conditions for improving the anti-cracking and anti-seepage ability, anti-freeze-thaw, anti-shear, anti-fatigue and anti-impact of concrete, it is recommended to add 2~8kg of basalt fiber in one cubic meter of cement concrete.
(1) Before the construction, the amount of basalt fiber should be calculated according to the amount of mixed concrete and packed separately. The fiber, sand, stone and cement should be added to the mixer at the same time;
(2) Firstly Dry mixing and then wet mixing, the mixing time is slightly extended by 10~20s than the concrete without mixing fiber to ensure that the fibers can be evenly mixed in the concrete.
The slump of fiber concrete should be strictly controlled. If the slump is too small, it will be not easy to slide, and stick the chute, it is also difficult to vibrate into the warehouse, the resistance is large when sliding the mold, the concrete is easy to be cracked; the slump is too large, the sliding in the chute is easy to separate, and the concrete is easy to collapse after the model, as the result, the flatness of the panel surface is poor, and the strength of the concrete cannot reach the design value.
(1) Transportation is the same as ordinary concrete, no special requirements;
(2) The basalt fiber concrete should be poured to ensure the uniformity of the basalt fiber distribution and the continuity of the structure. It is forbidden to add water due to the dryness of the mixture.
(1) When pouring, to vibrate with the plate vibrator in time, and the plug-in vibrator should be avoided as much as possible so as not to affect the fiber lap joint inserted into the vibrating position;
(2) If it is unavoidable, after vibrating with a plug-in vibrator, apply a flat vibrator for another 20 seconds to restore the three-dimensional distribution of the fiber;
(3) Sufficient vibration reduces the shrinkage stress of concrete, meanwhile, the cohesiveness of concrete increases, which effectively prevents the segregation of concrete.
There is no special requirement for the smoothing and curing of basalt fiber concrete, which can be carried out according to the requirements of conventional concrete specifications.
Guideline for basalt fiber composite reinforced concrete in the road (bridge) surface and tunnel paving leveling layer
The basalt fiber composite rib is a fiber reinforced building material, which should minimize the drag on the ground, prevent the surface from being smoothed and reduce the grip strength of the concrete.
Replace the original steel mesh pavement with equal spacing and equal strength. According to the normal use of tensile design, the use of basalt fiber composite ribs instead of steel bars should ensure that the tensile strength of the bearing capacity is consistent.
1) Since the basalt fiber composite ribs are coiled for continuous production, high-speed cutting saws should be used for cutting, but not by shearing;
(2) On-site cutting should be based on the construction design drawings and on-site working conditions to make overall planning lengths, and do the preliminary work for the next reinforcement and lashing.
The layout of the basalt fiber composite reinforced mesh shall be carried out in strict accordance with the requirements of the construction drawings:
(1) When laying the ribs, try to straighten the vertical and horizontal ribs, use stainless steel wire for lashing, and do not leak;
(2) Pay attention to the length when lap joint, it shall not be less than 35d; there shall be not allowed two lashing joints on the same vertical section, and the adjacent lashing joints shall be staggered by more than 500mm.
Before pouring concrete, the laid nets should be inspected and the concrete should be poured after the acceptance is passed.
Provide technical support and services
1.Can be used feeder controlled by a microcomputer ;
2.Can be used manually adding;
3.On-site technical support in accordance with project scale are available;
4.Vibration stirrer related equipment and technical services are available.