Summary of the invention
Technical problem to be solved by this invention is: a kind of porous thermal conductive asphalt concrete pavement heat exchange system is provided, this system can large scale collection, exchange and storage solar heat, and heat is used for building heating or refrigeration, can prevent the high temperature deformation, cold cracking of asphalt roads and deicing or snow melting effectively simultaneously.
The present invention solves its technical problem and adopts following technical scheme:
Porous thermal conductive asphalt concrete pavement heat exchange system provided by the invention, it comprises: be laid on the asphalt concrete pavement heat exchange device on the roadbed, this device is made up of the first dense-graded asphalt concrete surface layer that is arranged in order from top to bottom, porous thermal conductive asphalt concrete pavement, emulsified bitulith seal and the second dense-graded asphalt concrete surface layer with prefabricated closely knit demarcation strip segmentation; Be provided with silicon rubber waterproof permeable formation, be distributed in described two dense-graded asphalt concrete surface layers the surface and infiltrate through in the inside of this surface layer; By pipeline and blower fan, asphalt concrete pavement heat exchange device, thermal storage device, auxiliary thermal source, user's heat interchanger are coupled together, constitute the thermal cycle closed-loop path of native system, and adopt air as heat transferring medium.
Porous thermal conductive asphalt concrete pavement heat exchange system provided by the invention, it is used to collect the maintenance on solar energy, road surface and to the building heating refrigeration.
Principle of the present invention is: during summer high temperature, utilize circulating air to pass through the road surface loose structure, the heat that the road surface absorbs is taken away, be stored in the thermal storage device or be used for air conditioner refrigerating.During winter, system extracts the heat that stores, and is used for the road surface of flowing through again after building heats, and prevents that road surface accumulated snow from freezing, cold cracking.
The dark asphalt road area is big, absorptive capacity is strong, its absorption coefficient can reach 0.9, pavement temperature can be up to 70 ℃ when summer high temperature, and the thermal property and the heat-exchanger rig of solar energy utilization ratio and bituminous mixture is closely related on the flexible pavement, the coefficient of thermal conductivity of general bituminous concrete is 1.5~2.0W/mK, porous asphalt concrete lower, and its solar energy utilization ratio is 15%~20%.Increase the coefficient of thermal conductivity of ground surface material, can reduce road table radiation heat loss, accelerate the transmission of heat, thereby be beneficial to the raising solar energy utilization rate.The heat exchange efficiency height of heat-exchanger rig has directly influenced the collection of solar energy, domestic have patent to propose the method for utilizing U type pipeline to carry out heat exchange, porous thermal conductive asphalt concrete heat-exchanger rig is big with respect to interior its heat exchange area of the U of burying type pipeline heat-exchanger rig, the intricate turbulent heat transfer of having strengthened in space, so have the high characteristics of heat exchange efficiency; This device utilizes the heat exchange of bituminous concrete body to avoid pipeline and pavement durability matching problem simultaneously.The present invention prepares the porous thermal conductive type flexible pavement heat-exchanger rig that heat conductivility, pavement performance have both by admixture thermal conductivity filler, if use this device, flexible pavement is fully utilized, can alleviate China's energy-intensive situation greatly and reduce the discharging of CO2.
The present invention pays the utmost attention to the concrete pavement performance of porous thermal conductive asphalt on the basis that guarantees the design void content, press the different volumes of fiber and high viscosity modifier, adopt the test of dispersing, immersion Marshall Test, freeze thawing diametral compression test, combined type wheel tracking test, low temperature bend test evaluation loose structure whether qualified.Change asphalt content by the different volumes of thermal conductivity filler again, whether verification it satisfy performance requirement.
The present invention is according to the different volumes of thermal conductivity filler, the rolling legal system of T0703-1993 in " highway engineering pitch and bituminous mixture testing regulation " is made the method for rut plate test coupon and improved making combined type rut plate, the long 300mm of test specimen * wide 300mm * high 150mm carries out dynamic stability test.The result shows: the whole rut degree of depth is less than 5mm, wherein porous layer is contributed maximum to the rut degree of depth but is no more than 3mm, the crowded structure of skeleton embedding when showing high temperature in the porous asphalt concrete plays a part certain to rutting resistance, and the influence of pitch, thermal conductivity filler is extremely limited.
The present invention adopts the transient state plane heat source method to measure the effective thermal conductivity of porous thermal conductive type bituminous concrete, and in conjunction with the wind tunnel simulation test, has calculated the concrete heat exchange efficiency of porous thermal conductive asphalt.The result shows: the coefficient of thermal conductivity of heat-conducting type bituminous concrete, thermal diffusivity increase along with the increase of thermal conductivity filler volume; Heat exchange efficiency increases along with the increase of bituminous concrete coefficient of thermal conductivity.
In sum, the present invention compared with prior art mainly contains following advantage:
1. improve traffic safety: cold snap can prevent that road surface accumulated snow from freezing the traffic safety hidden danger of having avoided ice and snow to cause;
2. increase the stability and the durability on road surface: native system can avoid flexible pavement in the coldest thermal field acute variation when the hottest, significantly reduced the generation of low temperature crack and high temperature deformation, thereby prolong the application life on road surface, reduced the road maintenance cost indirectly;
3. environmental protection: give the building heating refrigeration, reduce the use of traditional fuel, thereby reduce CO
2Discharging; Deicing or snow melting does not need to use snow melting salt simultaneously, stops the negative effect of snow melting salt pair environment;
4. utilize rock-bed thermal storage device, underground or water accumulation of heat, realized that store the season of striding of solar energy;
5. China's solar energy resources is abundant, and it is wide to distribute, and possesses the advantage of sustainable development and utilization;
6. native system is in application process, and running cost and maintenance cost are low, and has realized zero environmental.
The specific embodiment
The present invention is a kind of porous thermal conductive asphalt concrete pavement heat exchange system, its structure as shown in Figure 1 and Figure 2, comprise: be laid on the asphalt concrete pavement heat exchange device 1 on the roadbed, its structure is to be the first dense-graded asphalt concrete surface layer 9, the porous thermal conductive asphalt concrete pavement 10 with prefabricated closely knit demarcation strip 13 segmentations, emulsified bitulith seal 14 and the second dense-graded asphalt concrete surface layer 11 successively from top to bottom.By ventilating duct 5, blower fan 6 and three way cock 7, asphalt concrete pavement heat exchange device 1, thermal storage device 2, auxiliary thermal source 3 and user's heat interchanger 4 are coupled together, constitute the thermal cycle closed-loop path of native system, and adopt air as heat transferring medium.
Above-mentioned porous thermal conductive asphalt concrete pavement 10 is composited by coarse aggregate, fine aggregate, pitch, thermal conductivity filler, breeze, fiber and high viscosity modifier, and their percentage by weight is respectively: coarse aggregate 45~69%, and particle diameter is greater than 4.75mm; Fine aggregate 12~20%, particle diameter is at most 4.75mm; Pitch 5.0~9.0%; Thermal conductivity filler 8~15%; Breeze 2~5%; Fiber 0.3~0.5%; High viscosity modifier substitutes 12~18% of pitch weight.The thermal conductivity filler is a kind of in carbon black, graphite powder and the carbon fiber, or multiple mixture.Fiber adopts polyester fiber, lignin fibre or mineral fibers.High viscosity modifier is the special-purpose thermoplastic elastomer TPS (TafPack-Super) of porous asphalt concrete.In the edge placement of porous thermal conductive asphalt concrete pavement 10 the saturating wall type air chimney 17 of long 40~45mm, diameter 25~30mm, the degree of depth that length 25~35mm porous end of saturating wall type air chimney 17 is implanted in the porous thermal conductive asphalt concrete pavement 10 are 30~40mm.Porous thermal conductive asphalt concrete pavement 10 adopts seal sleeve 16 sealings have air chimney interface 15 after by closely knit demarcation strip 13 segmentations.Saturating wall type air chimney 17, seal sleeve 16 are arranged in porous thermal conductive asphalt concrete pavement 10 work progresss simultaneously.Concrete arrangement is seen Fig. 3.
Described porous thermal conductive asphalt concrete pavement 10, its thickness are 50~60mm, and effective thermal conductivity is 2.50~5.20W/mK, permeability 0.05~1.8d, and the void content scope is 20%-28%, wherein the connectivity gap rate is not less than 18%.
The described first dense-graded asphalt concrete surface layer 9, its thickness is 40~50mm, and the void content scope is 3%~5%, and wherein the connectivity gap rate is at most 0.5%.By closely knit demarcation strip 13 segmentations such as prefabricated bituminous concrete, cement concrete, plastics or rubber tiles, the thickness of this closely knit demarcation strip thickness and porous thermal conductive asphalt concrete pavement 10 is equal in the porous thermal conductive asphalt concrete pavement 10.
The described second dense-graded asphalt concrete surface layer 11, its thickness is 120~150mm, void content scope 3%~6%, wherein the connectivity gap rate is at most 0.5%.
Described emulsified bitulith seal 14, by gather materials, mulseal, filler, water and Admixture form, thickness is 10~15mm, wherein the connectivity gap rate is at most 0.5%.Filler is breeze or cement.Mulseal is by the modified emulsifying asphalt of buying on the market, or common heavy friendship mulseal.Admixture comprises demulsifier, dispersing agent, curing compound etc.
The emulsified bitulith seal has following characteristics: prevent that heat to 11 diffusions of the second dense-graded asphalt concrete surface layer, reducing the road surface heat waste; Under the first dense-graded asphalt concrete surface layer, 9 inevitable situations, ftracture, protect the second dense-graded asphalt concrete layer 11 not to be subjected to the infringement of water, keep the durability of road structure.
Asphalt concrete pavement heat exchange device 1 by gather materials, pitch, fiber and thermal conductivity filler constitute, wherein: gathering materials is basalt, dolomite, granite, limestone or quartzite; Pitch adopts heavy traffic paving asphalt or modified bitumen; The thermal conductivity filler is a kind of in carbon black, graphite powder and the carbon fiber, or multiple; Fiber adopts polyester fiber, lignin fibre or mineral fibers.
After the first dense-graded asphalt concrete surface layer 9 and the second dense-graded asphalt concrete surface layer 11 have been constructed, spray one deck osmosis type silicon rubber waterproof agent, form silicon rubber waterproof permeable formation 12, with the infiltration that prevents air and the infringement of later stage water.
Porous thermal conductive type flexible pavement heat-exchange system provided by the invention is used to collect the maintenance on solar energy, road surface and to the building heating refrigeration.And realize the maintenance on solar heat-preservation, road surface and to the heating and the refrigeration of building by following steps.
A. as Fig. 1, Fig. 2 and shown in Figure 3: set up by being laid on the thermal cycle closed-loop path that asphalt concrete pavement heat exchange device 1, thermal storage device 2, auxiliary thermal source 3, user's heat interchanger 4, blower fan 6 on the roadbed constitutes native system.Porous thermal conductive asphalt layer of concrete 10 sealings that the road both sides is provided with in ventilating duct 5 and the road asphalt layer of concrete are connected, and heat are taken or imported out of the road surface.
B. as shown in Figure 1: utilize asphalt concrete pavement heat exchange device 1 to collect solar energy, the cold air that blasts by blower fan 6 carry out forced heat-exchanging and with heat delivery to thermal storage device 2, heat is stored.Therefore pavement temperature also reduces, and can prevent the road surface high temperature deformation.During summer, the heat that the state of change three way cock 7 is collected the road surface transfers to user's heat interchanger 4, utilizes the absorption refrigeration air-conditioning to be architecture refrigerating again.
C. as shown in Figure 1: during cold season by blower fan 6 heat removal from thermal storage device 2, by changing the state of three way cock 7, the user's heat interchanger 4 that makes near the extremely building 8 of heat delivery is delivered to the road surface again and is used for pavement snow melting ice and prevents road surface low temperature draw for the building heating.
Introduce several preparation examples below about porous thermal conductive asphalt concrete pavement 10.
Example 1, example 2 and example 3:
The percentage by weight of the concrete composition of plain asphalt is in the example 1: coarse aggregate 54%, fine aggregate 26%, pitch 6.5%, graphite powder 0%, breeze 13.5%.
The composition percentage by weight of heat-conducting type bituminous concrete is in the example 2: coarse aggregate 54%, fine aggregate 26%, pitch 6.5%, graphite powder 11%, breeze 2.5%.
The concrete composition percentage by weight of porous thermal conductive asphalt is in the example 3: coarse aggregate 62%, fine aggregate 19%, pitch 4.5%, graphite powder 11%, breeze 2.5%, TPS modifier 1.5%, polyester fiber 0.3%.Its correlated performance index is as shown in table 1.As shown in Table 1, behind the admixture graphite powder, the coefficient of thermal conductivity of porous asphalt concrete is brought up to 2.69W/mK by 1.52W/mK; Other performances satisfy the design specifications requirement.
The proportioning of pressing example 1 generates upper layer and following surface layer, and surface layer carried out the combined type rut during the proportioning of example 3 generated, and tested to such an extent that its dynamic stability is 4152 times/mm, and the whole rut degree of depth is 4.73mm.Cut the rut plate open back from the test position and find that surface layer is contributed up 2.81mm to the rut degree of depth in the porous, but still meets design requirement.
Example 4 and example 5:
The concrete composition percentage by weight of porous thermal conductive asphalt is in the example 4: coarse aggregate 62%, fine aggregate 19%, pitch 4.5%, graphite powder 9%, breeze 3.5%, TPS modifier 1.5%, carbon fiber 1%, polyester fiber 0.3%.
The concrete composition percentage by weight of porous thermal conductive asphalt is in the example 5: coarse aggregate 62%, fine aggregate 19%, pitch 4.5%, graphite powder 9%, acetylene carbon black 2%, breeze 2.5%, TPS modifier 1.5%, polyester fiber 0.3%.
The porous thermal conductive asphalt concrete that example 4 and example 5 are prepared, its performance indications see Table 2.As shown in Table 2, in the example 4, behind admixture 9% graphite powder+1% carbon fiber, the coefficient of thermal conductivity of porous asphalt concrete reaches 4.96W/mk, and the cleavage strength ratio is 85.9%, 4629 times/mm of dynamic stability.In the example 5, behind admixture 9% graphite powder+2% acetylene carbon black, the coefficient of thermal conductivity of bituminous concrete reaches 3.32W/mK, and the cleavage strength ratio is 83.2%, 4123 times/mm of dynamic stability.Their void content still remains on more than 23%, helps heat convection.
Example 6 and example 7:
Example 6 and example 7 have all been simulated heat transfer process.
In the example 6, adopt common thermal conductive asphalt concrete heat-exchanger rig, inside is provided with double-U-shaped pipeline, and surface simulation solar energy is provided with constant thermal source, passes to WATER AS FLOW MEDIUM in pipeline.
Adopt porous thermal conductive asphalt concrete heat-exchanger rig in the example 7, three layers of upper, middle and lowers, thickness all be 50mm, middle surface layer seals with the wind tunnel test instrument and links together, and identically with example 6 constant thermal source is set on layer in the above.
Example 6 is as shown in table 3 with the heat exchanger effectiveness of example 7: as heat exchanger, the heat exchange efficiency of the heat-exchanger rig of example 6 reaches 20%~30% with common thermal conductive asphalt concrete, and the heat exchange efficiency of the heat-exchanger rig of example 7 can reach 25%~36%.Be scaled solar energy, the road surface that example 6 is annual every square metre can provide the energy of 140~200KWh, and wherein 20%~30% energy is used for pavement snow melting ice, and all the other 70%~80% also can make other purposes; The road surface that example 7 is annual every square metre can provide the energy of 170~250KWh, and wherein 15%~24% energy is used for pavement snow melting ice, and all the other 76%~85% also can make other purposes.
Subordinate list
Table 1 bituminous concrete correlated performance index table
Performance parameter |
Example 1 |
Example 2 |
Example 3 |
Technical requirements |
Void content (%) |
4.0 |
4.0 |
24 |
- |
Coefficient of thermal conductivity (W/mK) |
1.52 |
3.60 |
2.69 |
- |
Cleavage strength is than (%) |
0.92 |
0.82 |
0.84 |
- |
Stability (kN) |
12.1 |
8.3 |
5.9 |
≥3.5 |
Residual stability (%) |
93.0 |
81.2 |
83.3 |
≥80 |
Dynamic stability (inferior/mm) |
6210 |
5260 |
4452 |
≥3000 |
Cleavage strength is than (%) |
93.5 |
82.4 |
84.6 |
≥75 |
Low temperature (10 ℃) bending strain (μ m/m) |
2510 |
2450 |
2322 |
≥2300 |
The loss late of dispersing (%) |
5.5 |
7.8 |
13.2 |
≤20 |
Table 2 admixture carbon fiber and acetylene carbon black porous thermal conductive asphalt concrete correlated performance index table
Performance parameter |
Example 4 |
Example 5 |
Coefficient of thermal conductivity (W/mK) |
4.96 |
3.32 |
Void content (%) |
25.3 |
23.5 |
Cleavage strength is than (%) |
85.9 |
83.2 |
Dynamic stability (inferior/mm) |
4629 |
4123 |
Table 3 porous thermal conductive asphalt concrete heat exchange efficiency
Performance parameter |
Example 6 |
Example 7 |
Heat exchange efficiency (%) |
20~30 |
25~36 |
Available energy (KWh/m
2·a)
|
140~200 |
170~250 |
Be used for road surface heat (%) |
20~30 |
15~24 |
Be used for building heating (%) |
70~80 |
76~85 |