Two, background technology
The background technology of present road surface base layer material and mulseal purposes aspect
1, the stabilized with inorganic binder basic unit's (semi-rigid type base) that gathers materials
Stabilized with inorganic binder is gathered materials, be with inorganic binder (cement, lime, flyash etc.), gather materials (rubble, gravel etc.) and water mixing and stirring, become the suitable semi-rigid type base compound that rolls, then with its making on roadbed, after rolling, road roller forms the road surface semi-rigid type base, as cement stabilized macadam base, cement Stability Gravel basic unit, lime fly ash crushed rock base course etc.No matter Pavement on Semi-rigid Type Base is ordinary highway, or speedway in our country, has all obtained a large amount of application.The flexible pavement or the cement pavement of more than 30,000 kilometer speedway of China, basic unit all is semi-rigid type base more than 90%, semi-rigid type base has been brought into play very big effect in the highway construction development of China.
The advantage of semi-rigid type base is: the semi-rigid type base strength ratio is higher, relative flexibility basic unit intensity height, rigidity height, and as load-carrying members, it is proper.Carrying, diffusion load pass to roadbed, and this respect performance is not relatively good before semi-rigid type base has cracking.But there are some problems in semi-rigid type base, is exactly that plastic shrinkage cracking is more serious, and resistance to tension compares less, and deformability is not so good, is more crisp material.Its ratio of rigidity is bigger, in the humidity transformation temperature changes suffered thermal stresses greatly, so at temperature load, traffic loading, under the effect that humidity changes, it is easy to generate the crack, semi-rigid type base character begins to change after the cracking.These crackles are easy to form the reflection crack of flexible pavement, and particularly under the many situation of later stage crackle, crackle is easy on the relatively shorter time just reflexes to, and a lot of actual engineerings have proved this problem.This is at present semi-rigid asphalt pavement to be thought the place of its deficiency.
In order to prevent reflective crack, China road expert has also done some researchs in the enforcement period of the seventh five-year plan, for example as adopting graded broken stone, geotextiles and stress absorbing layer as some measures such as intermediate layers, to recently, the similar 20 years time, is still also groping.The research reflective crack, how to delay it, prevent it is impossible fully, how to prolong its expansion time, make its crack deflection long, keep the long time of surface can not ftracture, done a lot of work in this respect to the time on the face, obtained some achievements, but this problem does not solve fully also till now yet.
Semi-rigid type base has also been found some problems in work progress, relatively more difficult such as the priming oil infiltration, also have the semi-rigid type base surface to be easy to generate dust, unclean if the generation dust is cleared up when constructing later on, just influenced the bonding of adhesion coating and semi-rigid type base.After the pavement cracking, go under water just to damage easily in addition.After semi-rigid type base has problems, must all dig up it and could repair, like this with regard to some difficulty.
Therefore, talk about semi-rigid type base now, we should suit measures to local conditions to consider this problem.If condition is suitable, semi-rigid type base still can be used in some place, it also is not right that but semi-rigid type base rules all the land, no matter be from enriching the angle of China's road structure form, still from overcoming the angle of Pavement on Semi-rigid Type Base cracking problem, the research of carrying out other type base material is very necessary.
2, roll cement concrete basic unit (rigid base)
Rolling cement concrete is a kind of new concrete that grows up in the last thirty years.It has particular performances, the performance of roller compacted concrete is not different from conventional concrete fully before not solidifying, not solidified roller compacted concrete denseness is very dried, no slump concrete than worker China Democratic National Construction Association is also done, be that a kind of slump is zero super no slump concrete, it can make bulldozer, road roller work and do not sink thereon, and is very approaching with the concrete performance of routine again after solidifying.Roller compacted concrete makes stone overcome frictional resistance and occupies space formation skeleton by the effect of road roller vibration force, and hole is filled and wrapped up by cement mortar, forms compacting body.
Roll that cement concrete has that the construction machinery capacity is big, speed is fast, the characteristics of large tracts of land operation.Roll cement concrete and have similar workability to semi-rigid sub-base material, but cement consumption was greater than the consumption of inorganic binder in the semi-rigid sub-base material during its material was formed, therefore will roll cement concrete as sub-surface, will have better performance at aspects such as intensity, durability, scour resistances than semi-rigid type base.
Roll cement concrete and aspect the build of the build of water conservancy project dam body and high grade highway pavement more application is being arranged.Roll cement concrete basic unit from material property, still belong to the category (rigid material) of conventional cement concrete, it is out of shape bad adaptability, fragility is big, crack resistance is poor.Therefore if do not establish the shrinkage joint, the crack appears in regular meeting in the road surface, at present when pavement construction, usually every 10~15m a shrinkage joint is set in the road surface.
In recent years, for raising rolls the cracking resistance of cement concrete, what steel fibre occurred mixing rolls the road structure of cement concrete as surface layer, and its research at home and abroad is just at the early-stage.External steel fibre rolls cement concrete and shows as the road structure engineering applicable cases of surface layer, the functional performance on road surface and durability are improved and improve, but (generally mix 30kg~40kg in every cubic meter of concrete because the volume of steel fibre is higher, even it is higher), involve great expense, and in the roller compacted concrete of moisture content less, mix the steel fibre of rigidity, fiber is difficult for disperseing, mix and stir difficulty, it is not too convenient to construct, therefore, steel fibre rolls applying of cement concrete and has been subjected to certain restriction.
At present, flexible fiber has obtained certain application in common casting cement concrete, and the result shows that the mechanical property that toughening effect has significantly improved cement concrete is split in the resistance of flexible fiber, makes cement concrete have good cracking resistance and anti-fatigue performance.The application of flexible fiber in rolling cement concrete basic unit also certainly will have excellent generalization values, but up to the present, this technology does not cause people's attention as yet.
3, the stable basic unit's (flexbile base) that gathers materials of hot asphalt
Flexbile base is to be different from that stabilized with inorganic binder is gathered materials or semi-rigid type base such as Stabilized Soil, with gather materials, the gathering materials or the basic unit of material makings such as organic binder compound such as pitch of small amounts of inorganic binder punishment.At present, the pitch stabilization gravel is a kind of common flexbile base.
The pitch stabilization gravel compares with semi-rigid type base, because its modulus of elasticity is little, so its situation aspect variations in temperature generation stress influence is better relatively than semi-rigid type base, effects of humidity change also wants littler simultaneously, so it is embodying good advantage aspect the road reflection crack that the minimizing base course crack causes.
Interrelated data proves that the destruction on pitch stabilized macadam base road surface generally starts from surface layer, because destruction order development from top to bottom, extensions such as the rut of surface layer, crackings.Often can self-healing for the inner minute crack that occurs in pitch stabilized macadam base road surface, and be unlikely the picture semi-rigid sub-base material, the crack appears and after, expansion rapidly, so the destruction on pitch stabilized macadam base road surface is functional destruction.
But, in pitch stabilized macadam base road structure, tensile stress at the bottom of basic unit's layer is bigger, the possibility that occurs layer end fatigue cracking under the effect repeatedly of flexural tensile stress is also maximum, therefore require to have good durability, have good anti-fatigue performance especially, and require to have certain rutting resistance and stability, pitch stabilized macadam base to await in this respect to improve as bearing course.
In addition, pitch in the stable basic unit that gathers materials of existing pitch generally is to adopt hot asphalt, need pitch is heated to about 150 ℃~160 ℃, gather materials and be heated to about 160 ℃~175 ℃, pitch should be controlled at 150 ℃~165 ℃ with the temperature of dispatching from the factory of mixing and stirring the back compound of gathering materials, the temperature that paves is not less than 145 ℃, the first pressing temperature is not less than 135 ℃, the final pressure temperature generally is not less than 80 ℃, and just can not construct when temperature is low in the winter time, therefore, stable the mixing and stirring of gathering materials of hot asphalt, construction requirement is higher and complicated, and simultaneously, hot asphalt is contaminated environment not only, and pitch is in for a long time and also will speed up the aging of pitch under the high temperature, influence pitch and stablizes the durability of gathering materials.
4, mulseal and uses thereof
Mulseal is the uniform asphaltic products of the oil-in-water shape made through emulsification processing under mechanism of matrix pitch, water, emulsifier and stabilizing agent, also claims asphalt emulsion.
When using this asphalt emulsion to repair the roads, need not heat, can spray at normal temperatures, injection or mix and stir and pave the surface layer and the basic unit on the various structures of making road surface, the maintenance that can be used as priming oil, sticking layer oil yet and be used for various stabilized bases.Than hot asphalt, the application market of mulseal is very extensive, and particularly current slurry seal of wideling popularize in the whole nation and Modified Slurry Sealing replace heated bitumen and modification heated bitumen with mulseal and modified emulsifying asphalt.
Slurry seal is that thickness is 5mm~10mm, plays effects such as waterproof, health, joint seal, bonding, stress absorbing membrane interlayer with the deck of compound making in basic unit of mulseal and fine aggregate.Have behind the emulsified asphalt slurry seal breakdown of emulsion with ordinary hot and mix the essentially identical physics of asphalt slurry seal coat, mechanical property, but its constructing operation and construction requirement obviously oversimplify, but also have the asphalt content of saving, reduce advantages such as environment pollution.
Three, summary of the invention
The purpose of this utility model is: adopt mulseal to gather materials and mix flexible fiber as cementitious matter is stable, the performance mulseal economizes on resources, prolong construction seasons, improve execution conditions, reduce the advantage of environment pollution, the resistance of bringing into play flexible fiber is simultaneously split toughness reinforcing, antifatigue and the effect of stablizing pitch, improve the cracking resistance of compound, shock resistance, resistance to deformation, freeze proof, antiscour, anti-fatigue performance and high temperature, low-temperature stability, and with it as the stable sub-surface that gathers materials of flexible fiber mulseal, through rolling making on bottom, and then on the stable sub-surface that gathers materials of flexible fiber mulseal the making surface layer, constitute together that a kind of flexible fiber mulseal is stable to gather materials as the road structure of basic unit.
The technical scheme that the utility model purpose is taked is as follows:
Road structure of the present utility model, include surface layer, flexible fiber mulseal stable gather materials sub-surface, bottom, at the stable sub-surface that gathers materials of bottom surface making flexible fiber mulseal, stablize making surface layer on the sub-surface that gathers materials at the flexible fiber mulseal then.
The utility model, the stable sub-surface that gathers materials of flexible fiber mulseal is by flexible fiber, mulseal, cement, (rubble or gravel) gathers materials, filler, Admixture and water etc. are formed and formation adhered to one another behind mix, wherein flexible fiber weight is stable 0.01%~0.2% of the compound gross weight of gathering materials of pitch, mulseal is 4%~9% with the percentage by weight that gathers materials (being the mammary calculus ratio), cement weight is 1%~4% of the gross weight of gathering materials, filler is 0~10% of the gross weight of gathering materials, Admixture is 0~2% of a mulseal, water is 0~4% of the gross weight of gathering materials, and forms the stable sub-surface that gathers materials of flexible fiber mulseal through rolling.
The utility model, surface layer can be Portland Cement Concrete Surface Course or asphalt concrete pavement, also can be the surface layers of other any modification ground surface material making.
The utility model, bottom can be roadbeds, also can be the basic units of various types: as semi-rigid type base, flexbile base or rigid base; Also can be original road surface of old road: as cement concrete pavement, perhaps flexible pavement.
The utility model, flexible fiber is meant with respect to rigid fiber (high-elastic modulus fibre, as steel fibre), modulus of elasticity is less than the low-elasticity-modulus organic synthetic fibers of cement concrete bullet mould, as polypropylene fibre, polyacrylonitrile fibre, polyester fiber, polyamide (nylon) fiber etc.Mix flexible fiber in gathering materials in that mulseal is stable, the effect that the resistance of performance flexible fiber is split toughness reinforcing, antifatigue and stablize pitch improves mulseal and stablizes the cracking resistance of the compound that gathers materials, shock resistance, resistance to deformation, freeze proof, antiscour, anti-fatigue performance and high temperature, low-temperature stability etc.
The utility model is a kind of new road structure pattern, and it has following advantage:
(1) compare with stable gathering materials of existing hot asphalt, stable gathering materials of flexible fiber mulseal can be saved asphalt content, has the advantage of conserve energy resources, good economy performance.
(2) compare with the stable basic unit that gathers materials of existing hot asphalt, the stable basic unit that gathers materials of flexible fiber mulseal adopts the cold mixing method construction to have significant advantage, and be in particular in: technology is simple, speed is fast, has saved operating expenses; Prolonged construction seasons; Reduced the pollution of environment; Mulseal all has good adhesive property with dried, wet gathering materials, and has reduced the requirement to the humidity that gathers materials.
(3) the flexible fiber mulseal is stable has added a certain amount of cement in gathering materials, help improving the early strength of compound, simultaneously by mulseal, the adjustment of cement consumption and the selection of different fiber types, can make the stable basic unit that gathers materials of flexible fiber mulseal under the prerequisite that guarantees good cracking resistance and deformation performance, adjustability with intensity, rigidity, can satisfy different user demands, thereby have widely applicable advantage.
(4) the flexible fiber mulseal is stable gathers materials as basic unit, has improved the internal construction of base material and has formed, and has reduced the generation of inner microcrack, therefore helps improving the combination property of base material.
(5) the flexible fiber mulseal is stablized the plastic shrinkage that disorderly also helps reducing basic unit in the basic unit that gathers materials to the flexible fiber that distributes, and strengthens the anti-crack ability and the deformability of basic unit, reduces the generation in road reflection crack.
(6) the flexible fiber mulseal is stable gathers materials that to have a rutting resistance good, and high temperature, low-temperature stability are good, the advantage of good endurance.
(7) compare with existing semi-rigid type base, rigid base, flexbile base road structure, in the stable road structure that gathers materials as basic unit of flexible fiber mulseal, base material has anti-contraction, cracking resistance is strong, good toughness, shock resistance, freeze proof, antiscour, antifatigue, high temperature, the advantage that low-temperature stability is good, therefore the stable road structure that gathers materials as basic unit of flexible fiber mulseal has better pavement performance and durability, has significant indirect economic effect and social benefit.
(8) compare with existing semi-rigid type base, rigid base, flexbile base road structure, under the prerequisite that guarantees pavement performance, the flexible fiber mulseal is stable to gather materials as the suitable thickness on attenuate road surface of the road structure of basic unit, has good economic benefit.
In sum, the utility model is a kind ofly both to be different from existing Pavement on Semi-rigid Type Base structure, to be different from existing rigid base road structure, also is different from the novel road surface structure of existing flexbile base road structure.
The utility model can with the condition of existing semi-rigid type base, rigid base or flexbile base road structure same base layer thickness under, improve the anti-contraction, cracking resistance, toughness, shock resistance of base material, freeze proof, antiscour, antifatigue and stability etc., improve the pavement performance and the durability of road; Can descend in the prerequisite that guarantees good pavement performance and durability and hang down the thickness on road surface, bring remarkable economic efficiency and social benefit; Simultaneously, stable gathering materials of flexible fiber mulseal draws materials conveniently, and construction is simple, quick, environmental protection.