CN203319874U - Concrete pavement with high water storage capacity - Google Patents

Concrete pavement with high water storage capacity Download PDF

Info

Publication number
CN203319874U
CN203319874U CN2013202233011U CN201320223301U CN203319874U CN 203319874 U CN203319874 U CN 203319874U CN 2013202233011 U CN2013202233011 U CN 2013202233011U CN 201320223301 U CN201320223301 U CN 201320223301U CN 203319874 U CN203319874 U CN 203319874U
Authority
CN
China
Prior art keywords
concrete
water storage
high water
aggregate
cement
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CN2013202233011U
Other languages
Chinese (zh)
Inventor
张纯洁
李海涛
周尚永
陈怡宏
张意
俞心刚
叶建雄
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Chongqing University
Chongqing Construction Engineering Group Co Ltd
Chongqing Construction Residential Engineering Co Ltd
Original Assignee
Chongqing University
Chongqing Construction Engineering Group Co Ltd
Chongqing Construction Residential Engineering Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Chongqing University, Chongqing Construction Engineering Group Co Ltd, Chongqing Construction Residential Engineering Co Ltd filed Critical Chongqing University
Priority to CN2013202233011U priority Critical patent/CN203319874U/en
Application granted granted Critical
Publication of CN203319874U publication Critical patent/CN203319874U/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Abstract

The utility model discloses a concrete pavement with high water storage capacity, which is used for solving the problem that an existing concrete walkway does not have characteristics of water permeability and water storage simultaneously. The concrete pavement with high water storage capacity in the scheme comprises a surface layer and a base layer and is characterized in that the surface layer is a concrete layer with high water storage capacity, a plurality of expansion joints with spacing of 4m-6m are formed in the surface layer, and rubber-plastic foaming rubber with thickness of 3mm-5mm is arranged in the expansion joints. Concrete does not contain fine aggregate, thin-layer cement paste covers the surface of coarse aggregate, which is bonded together, to form a honeycomb structure with uniformly distributed pores, and the honeycomb structure internally contains a very large proportion of unsealed communication holes. Therefore, the concrete pavement disclosed by the utility model has the characteristics of water storage, water permeability, gas permeability, light weight and the like. By virtue of the embedded type rubber-plastic material, the water permeability and water storage characteristics of the concrete can be kept long.

Description

High water storage concrete road surface
Technical field
The utility model relates to a kind of pavement structure that is exclusively used in path, walkway or cycle track.
Background technology
Along with developing rapidly of China's economy and Urbanization Construction, city size sharply expands, city's green areas is fewer and feweri, the substitute is a large amount of concrete roads and terrace, these material heat absorption capacities are strong, under sun direct projection, temperature on road is than the high 18 degrees centigrade of left and right of the temperature on soil, cement roof temperature is than the high 20 degrees centigrade of left and right of the temperature on meadow, and absorb heat daytime in a large number, continues distribute heat night.Wherein the black Color Reflectance of asphalt road is very low, and the heat of absorption will be much higher than light-colored place.In addition, because soil can not carry out thermal exchange and moisture control with earth's surface, so the urban surface temperature and humidity can't be regulated, urban heat land effect appears.Except large Climatic Effects, the quickening of Process of Urbanization Construction, the ground that raised growth green vegetation is replaced by concrete, make the heat energy produced after solar radiation can't be absorbed very soon, spread, caused the aggravation of urban heat land effect, in road surface, the evaporation of moisture can effectively reduce city temperature.Possess permeable, water storage two specific characters during due to normal concrete pavement difference, lack the reduction that water storage is unfavorable for city temperature, and lack water-permeable, can cause the surface gathered water in rainy season.
The utility model content
The utility model also provides a kind of high water storage concrete road surface, to solve the existing concrete pavement, does not possess problems permeable, water storage two specific characters simultaneously.
High water storage concrete road surface in this programme, comprise surface layer and basic unit, it is characterized in that, surface layer is high water storage concrete layer, and surface layer is provided with the expansion joint that the multiple tracks spacing is 4~6m, is provided with the rubber-plastic foamed plastic cement that 3~5mm is thick in expansion joint.
High water storage concrete in this programme comprises cement and coarse aggregate, include the common brick particle in coarse aggregate, cement shared mass percent in all material is 16%~25%, common brick particle shared mass percent in coarse aggregate is 20%~80%, the particle diameter of common brick particle is 5~10mm or 10~15mm, it is by coarse aggregate, cement, the cellular concrete that water and admixture stir into through certain stirring technique, not containing fine aggregate, coating pellicular water mud by the coarse aggregate surface mutually bonds and forms the equally distributed polynuclear plane in hole, the non-sealing communicating aperture that significant proportion is contained in its inside.Therefore there are water storage, the characteristics such as permeable, ventilative, lightweight.
High water storage concrete strength in such scheme is low than normal concrete, is more suitable for pavement etc. to the less demanding ground of supporting capacity.Must establish expansion joint during the pervious concrete pavement construction, seam is dark identical with road surface thickness.In the contracting seam of cutting surface layer, should adopt the flexible materials joint filling, and can not adopt the material of hot-fluid, in order to avoid the material of hot-fluid is penetrated in the space of high water storage type eco-concrete.Should not, with the flexible materials (as the material of similar glass cement) of mobility, embed the rubber and plastic plastic material of finalizing the design and should adopt, the concrete water-permeable of maintenance that can be more permanent and water storage.
Further: the construction joint that described expansion joint is thickness 3~5mm.
Because of the characteristic of high water storage type eco-concrete, inconvenience during construction, often adopt little expansion joint (E.J.) to replace expansion joint in reality.Conventional 5m should establish little expansion joint (E.J.) together in left and right, and pastes at the place, gap the rubber-plastic foamed plastic cement that pad connects, and thickness is generally 3~5mm.Usually during construction also available construction joint replace little expansion joint (E.J.), during construction, every 5m establishes rubber-plastic foamed plastic cement together in left and right.When construction length surpasses 30m, can establish the cutting expansion joint (E.J.), stitch the wide 15~20mm that is controlled at and be advisable.During highway engineering construction, every 5m should establish little expansion joint (E.J.) together in left and right, stitches wide 10~15mm.When construction length surpasses 30m, can establish the expansion joint that width is 10~15m.In construction, construction joint can replace expansion joint.
The accompanying drawing explanation
Below in conjunction with the drawings and specific embodiments, the utility model is described in further detail:
The schematic diagram of overlooking that Fig. 1 is high water storage concrete road surface in the utility model embodiment.
Embodiment
1 general introduction
1.1 because the high water storage concrete of this programme research is a kind of completely new concept, the domestic research that does not also have other researchists to carry out this aspect at present.But China is the uneven and in short supply country of a distribution of water resources, and high water storage concrete is a kind of environment-friendly type, environmental material, will day by day receive people's concern, and application prospect is boundless.
2 starting material and testing method
2.1 main raw material
2.1.1 cement
The weak link of high water storage concrete destruction is that the contact site between aggregate is the cement bond layer, and strength of cement is higher, and glued layer intensity is also higher.So the strength of cement grade is the important factor in order of pervious concrete intensity, higher grade of strength of cement pervious concrete intensity is also higher.Adopt Lafarge board P.O.42.5R silicate cement, the physical and mechanical property of cement and chemical composition are in Table 2.1 and table 2.2.
The Chemical Composition of table 2.1 cement (%)
SiO 2 Fe 2O 3 Al 2O 3 CaO MgO SO 3 Total alkali content Loss on ignition
22.04 2.65 6.29 58.99 2.53 2.47 0.72 3.06
The performance of table 2.2 cement
2.1.2 coarse aggregate
Research data shows, aggregate size is less, and aggregate piles up that porosity is larger and intergranular point of contact is more, and the high water storage concrete strength of preparation is higher.The concrete grain composition of high water storage is one of principal element determined its intensity and water storage.In order to guarantee the concrete intensity of high water storage and water storage function, coarse aggregate adopts the single-grade that particle diameter is less usually.This experiment adopts rubble and discarded common brick, its performance index in Table 2.3, table 2.4.
The performance of table 2.3 rubble (5~10mm)
The performance of table 2.4 rubble (10~15mm)
The performance of the waste and old fragment of brick aggregate of table 2.5
2.1.3 water
This research ordinary tap water.
2.2 testing method
2.2.1 the preparation of sample
2.2.1.1 stirring means
This experiment adopts cement to wrap up in the stone method: first aggregate is mixed in proportion, first stirs 2 minutes after the water wet surface, then add cement mixing one to two minute, finally add water and stir.Because high water storage concrete strength is mainly derived from the even parcel of cement slurry to aggregate, so cement is wrapped up in Shi Faneng under the prerequisite that keeps porous water storage concrete water storage performance, significantly improve its ultimate compression strength.
The another notes: because relate to waste and old fragment of brick as aggregate in test, so wrap up in before the stone method is mixed in proportion aggregate at cement, first waste and old fragment of brick is added separately to gauge water and stir and drench, operation is thereafter wrapped up in the stone method with cement and is as good as.
2.2.1.2 moulding process
Because cellular concrete is not identical with the portland cement concrete structure, so moulding process needs doscrimination.Normal concrete adopts vibratory compaction, is in order to make concrete as far as possible closely knit, thereby gains in strength and improve weather resistance.Yet, for cellular concrete, because its inside effective porosity is very large, if adopt vibratory compaction, grout cognition enters inside, space because of vibrations, and then affects its water storage performance.And coarse aggregate can friable state occur because the cement slurry parcel is irregular, greatly reduces upper surface intensity, thereby affects bulk strength.This experiment adopts the tamping molding mode.
2.2.1.3 maintenance method
Because there are a large amount of spaces in high water storage concrete, dehydration is very fast, so maintenance is relatively extremely important.Particularly in early days, note preventing the evaporation of moisture in concrete.Should put into standard curing room after specimen molding and carry out maintenance, 24 as a child form removals, put into standard curing room again after form removal, carry out normal curing.
2.2.2 experimental data measuring method
2.2.2.1 compressive strength determination
After test piece maintenance 28D, carry out the mensuration of ultimate compression strength.Concrete steps are as follows:
Test specimen is placed on to lower bearing plate, and the load bearing face of test specimen is vertical with the moulding end face.The press table center of trier should be aimed in the test specimen center.Start experimental machine, choose suitable range.While choosing range, should allow reading in full range 20% to 80% between, such reading is comparatively accurate.
In pressure process, should keep continuous uniform pressurization, the speed control of load application p.s. 0.5MPa between 0.8MPa.When test block is damaged distortion, close the oiling valve, and open oil return valve, take out test specimen.The recording meter panel reading, the reading of dial plate pointer is fully-factored load.
Ultimate compression strength is calculated as follows:
F=0.95*P/A
Wherein 0.95-dimension conversion coefficient while adopting non-standard test specimen
F-ultimate compression strength (MPa)
P-ultimate load (KN)
A-load area (0.01 ㎡)
The arithmetical av that records numerical value with every group of three test specimens is determined measured value.If the difference of one of them measured value and intermediate value surpasses the ten Percent five of intermediate value, getting intermediate value is measured value.If there is the difference of two measured values and intermediate value to be greater than ten Percent five, these group data are cancelled.
2.2.2.2 high water storage concrete pore rate testing method
The test experiments step is as follows:
Test specimen is put into to the drying in oven of 100 degrees centigrade to constant weight M 1, take out and cool to room temperature.Measure sample dimensions with ruler, its volume V in calculating.Test specimen is immersed in the water to 24H fully, makes in its space all to be full of moisture, the state that reaches capacity, take out standingly, measures weight M 2
According to formula P=(M 1-M 2The porosity of)/V calculation testing piece.
M wherein 1-constant weight after drying
M 2-water saturation weight
V-test specimen volume
2.2.2.3 the testing method of high water storage concrete water-intake rate and water-retentivity
Water retention test is with reference to having water-retentivity, absorptive concrete blocks (being called for short ILB) testing method.[9] try to achieve water-retaining capacity, and try to achieve the volume that moistening quality and adiabatic drying quality also have test specimen, substitution formula (8) is calculated.
Water-retaining capacity (g/cm 3Moistening mass M of)=( 1-dry mass M 2)/stone volume V (8)
In this test, every group guarantees 3 test blocks, test block is soaked into it fully being absorbed water in the clear water of 15~15 ℃ until after 24h by its taking-up, test specimen is inserted in the plastic containers of sealing, under 15~30 ℃ of room temperatures, standing 30min makes its evaporation moisture content, after wiping macroscopic moisture content with wet cloth, measure at once the quality of test specimen, obtain moistening quality.The adiabatic drying quality refers in the drying machine of 105 ± 5 ℃ of temperature, test specimen be dried to fixed mass, then in normal temperature cooled test specimen quality.
Water absorption test is to obtain the water regain of test specimen in 30 minutes.The drying machine inner drying that first test block is placed on to 105 ± 5 ℃ of temperature, to fixed mass, then makes it cooling in normal temperature.Be the method to set up of test I LB water absorption test device.Water level after arranging must exceed test block bottom 5mm, and water can be taken the clear water of 15~25 ℃.On the test specimen setting table, the bottom of test block is used as steel wire and so on and can be allowed the material of water flow fix.Take out concrete blocks after 30 minutes, with wet cloth, dry water droplet, it is not dripped, then quality measurement.The quality of measuring is the quality of water suction after 30 minutes.In addition, the same with water retention test, but water regain substitution formula (9) is tried to achieve:
Water regain (%)=(quality that absorbs water after 30min-adiabatic drying quality)/(moistening quality-adiabatic drying quality) * 100% (9)
2.2.2.4 the testing method of high water storage concrete permeable coefficient
At present, educational circles mainly contains the ordinary water level method and becomes two kinds of water level method the coefficient of permeability measuring method of pervious concrete.For the mensuration of porous drainage material permeability coefficient, some unit designed, designeds go out some permeability testing machines both at home and abroad, and the permeability testing machine that this experiment designs with reference to professor Yang Jing of Tsing-Hua University also carries out a small amount of permeability coefficient of testing high water storage concrete pavement material that improves.[6] the synthetic glass square frame that this equipment is both ends open, be of a size of 10 cm * 10 cm * 45cm, and scale (unit: cm), can be used for metering is carved with in the permeability testing machine front.Before measurement, first by the test specimen surrounding with sealing with wax, then permeability testing machine is placed in to the test specimen top, between permeability testing machine and test specimen, with the wax bar of half heat, seal, after the wax bar is cooling, more than adding water to 38 cm scales in permeability testing machine, when being down to 38 cm scale, underwater starts timing, and while dropping to 0 cm scale, timing is once again.The permeability coefficient calculating formula is:
K=H/△t (7)
In formula: H is the water level falling head, and this device is got 38 cm;
Time/s that △ t is water level decline H.
Each test block is surveyed 5 times, removes the highest, Schwellenwert, remaining 3 values substitution formula (7) of averaging.
2.2.2.5 the testing method of freeze-thaw resistance
Antifreezing test machine: can maintain the temperature at the refrigerating apparatus of-15 ℃.[8]
1. the water of standard specimen being put into to normal temperature soaks 25H, and during immersion, the water surface should exceed 20mm left and right, test specimen surface.
Taking-up test specimen after immersion completes, used wet towel to wipe the moisture of test specimen surface attachment, puts into immediately the antifreezing test machine.Sample is placed interval and is not less than 20mm, installs sample at every turn and returns to timed interval of-15 ℃ to temperature and should not surpass 2h.Start timing until temperature retrieval during to-15 ℃, freeze-off time is no less than 4h.
2. taking out test specimen puts into normal-temperature water and soaks 2h.This process is a freeze-thaw cycle, carries out successively freeze-thaw cycle 10 times.
3. after completing freezing and thawing test, wipe test specimen surface attachment water, check whether specimen surface has the crackle of peeling off and layering.
4. survey ultimate compression strength.
The freeze-thaw-loss of strength is calculated according to following formula: (R-R 0)/R*100%
Ultimate compression strength rate of loss (%) after-freeze-thaw cycle
R-compressive strength test test result mean value (MPa)
Test ultimate compression strength mean value (MPa) after R0-freezing and thawing test
Be accurate to 0.1%.
The concrete preparation and property research of 3 high water storage
3.1 high water storage mix Design
High water storage concrete has the characteristics such as intensity is low, porosity is high, open pore is many.Therefore when carrying out the sand-free coarse porous concrete mix Design, the parameter of mainly answering substitution to consider has water cement ratio (w/C), water consumption, aggregate-cement ratio (G/C).
Data shows proves that by the proportioning testing of materials specific a certain coarse aggregate is had to a best water cement ratio.When the water cement ratio of selecting is less than the best, easily cause grout too dry thick, the workability of concrete mix compares poor, and grout can't fully wrap up the coarse aggregate surface, is unfavorable for the raising of sand-free coarse porous concrete concrete strength; When the water cement ratio of selecting is greater than optimum value, grout is thinning, and stickiness reduces, and easily trickling, likely make the inside concrete hole partly or entirely stop up, and both reduced the inside concrete porosity, also without the raising that is beneficial to concrete strength.Second important parameter is water consumption, for the sand-free coarse porous concrete concrete, do not carry out in the ordinary course of things the workability test, must not carry out slump test yet, as long as all coarse aggregate particle surfaces of range estimation judgement all form the level and smooth parcel of grout uniformly, and integument has metalluster, cement paste not to trickle to think that water consumption is suitable.The 3rd important parameter is aggregate-cement ratio, and aggregate-cement ratio refers to the ratio of coarse aggregate consumption and cement consumption.Select applicable collection to detest ratio, can not only guarantee that the sand-free coarse porous concrete concrete has the hole at utmost mutually connected, and can large degree guarantee concrete intensity.[7]
The proportioning testing of materials proves, when cement consumption one keeps regularly, increasing aggregate-cement ratio, wraps up the grout layer thickness attenuation of coarse aggregate, thereby has increased concrete porosity, lowers concrete intensity; When cement consumption one timing, reduce aggregate-cement ratio, around the coarse aggregate particle, the grout layer thickness of parcel increases, and the concrete intensity of sand-free coarse porous concrete improves, but its porosity can reduce.Also need to consider the impact of above-mentioned parameter when we are designed according to method of design, both at home and abroad the concrete method of design of sand-free coarse porous concrete is had at present: look-up table, experimental formula method, volumetric method etc., this experiment adopts the experimental formula method.
Adopt equation design procedure and calculation formula to be:
(1) calculate the coarse porous concrete preparation strength.
fu,o=fcu,k/(1-dv) (1)
In formula: fu, o-preparation strength, MPa;
Fcu, k-design strength, MPa;
Dv---strength criterion is poor.
Should determine according to execute the data analysis that T unit accumulated in the past, if lack the data of this respect, also can search from table 3.1 according to the supervision of construction level of unit in charge of construction, can be taken as 25% when lacked the concrete experience of sand-free coarse porous concrete.
The relation of table 3.1 level of management and dispersion ratio dv
Level of management First class Second class Third class
d% <16 16~20 21~25
(2) estimate every cubic metre of cement consumption that pervious concrete is required.
mco=69.36+784.93fco,o/fce(2)
In formula: the cement consumption of mco-every cubic meter of concrete (referring to 4.25 class g cements), kg/m3;
Fce-cement observed strength (if without measured value, can take by 1.13 times of strength of cement grade points), MPa.
Formula (2) is built section the 4th innings by Guizhou and is provided, if cement, the larger problem of aggregate change are arranged, can be 20 kg by every cubic meter of concrete cement consumption difference, and be adjusted by intensity results.
(3) determine reasonable water cement ratio and water consumption.Water cement ratio is extremely important, in order to determine best water cement ratio, can be in the situation that cement consumption be certain, use the water cement ratio difference mixing of several differentiation from small to large, then measure their ultimate compression strength by test, draw again the graph of a relation of water cement ratio (W/C) and ultimate compression strength (f), obtain the corresponding optimum water cement ratio of maximum compressive strength.This method is relatively loaded down with trivial details, often rule of thumb judge in real work that whether water cement ratio is suitable, general some pervious concrete mixtures of mixing that take out are observed, if cement at the aggregate surface parcel evenly, there is no cement trickling phenomenon, and particle is rich in metalluster, illustrate that water cement ratio is more suitable.For general aggregate sand-free coarse porous concrete concrete such as rubbles, general water cement ratio can adopt following statistics empirical Calculation:
W/C=0.58-0.000715mco (manually entirely smashing method) (3)
W/C=0.5372-0.0007914mco (hammering plate method) (4)
Water consumption is mwo=W/C * mco.
But, while in coarse aggregate, common brick being arranged, common brick has than strong absorptive, when high water storage concrete-agitating and grout setting and harden, common brick can absorb the water in pervious concrete, thereby cause water cement ratio W/C to be less than the actual design value, high water storage concrete strength, freeze-thaw resistance will be affected, therefore must on the proportioning unit consumption of water, extra water distribution supplement the common brick absorption water yield.[10] this part water can take two kinds of modes to add, and a kind of is to make its surface reach surperficial surface dry condition after making common brick water suction before stirring saturated; A kind ofly be or solve by the final mixing water consumption of coarse aggregate water-intake rate calculative determination, common brick is put into the stirrer the inside and is mixed amount of water to make its surface reach water suction saturated, according to stirring technique, mixes successively stone, cement, water.Second method is taked in this experiment.Recording the relative water-intake rate that common brick absorbs water after saturated under state of nature is 14%, and rational water distribution rate is found out in the meter experiment, proportioning is in Table 3.2, water distribution quantity=common brick * water distribution rate, the water distribution rate gets 3%, 5%, 7%, 9%, 11%, 13%, 15%, according to adding common brick → water distribution → stone, the order of cement → proportioning water stirs, by gained test block maintenance 28 days record 28 days intensity levels under the natural curing state, analyze known, the best water distribution rate of 5~10mm grating is 9%, the best water distribution rate of 10~15mm grating is 7%, so two grating water distribution rates of this experiment are unified value 7%.
Table 3.2 water distribution quantity changes proportioning
(4) determine aggregate-cement ratio.The value of aggregate-cement ratio is determined with the sand-free coarse porous concrete concrete strength of required preparation, general for the sand-free coarse porous concrete concrete more than C10, between desirable aggregate-cement ratio 6:l~8:l, along with the reduction of sand-free coarse porous concrete strength grade of concrete, aggregate-cement ratio progressively increases, and generally can reach 15:l.
(5) determine every cubic metre of concrete coarse aggregate consumption of sand-free coarse porous concrete.Every cubic metre of concrete coarse aggregate consumption of sand-free coarse porous concrete can be taken as: the coarse aggregate quality of every cubic metre of compact state * 0.98 reduction coefficient.
When in this experiment, the particle diameter equivalent such as common brick replaces stone, the tightly packed density that every cubic metre of concrete coarse aggregate of sand-free coarse porous concrete (common brick, stone compound) consumption is every cubic metre of compound * 0.98 reduction coefficient.
(6) last trial mix make test specimen and join the reliability of intensity with the checking examination.
During the basic proportioning of this research and design, design strength is got 10MPa, and level of management get 25%, adopts hammering plate method, calculates water cement ratio W/C=0.35, finally lists the mix-design table in Table 3.3.
The basic mix-design table of the high water storage concrete of table 3.3
3.2 the research of high water storage concrete strength
Because high water storage type eco-concrete should have good water storage, good water-permeable is arranged again, therefore, the starting material of high water storage type eco-concrete select both to have required good intensity, require to have again good water-absorbent.This research is mainly to choose hard stone to serve as and carry high-intensity aggregate, selects to have some strength and the large common brick aggregate of water-intake rate increases concrete storage capacity.
The common brick aggregate obtains with waste and old common brick fragmentation, will obtain certain common brick powder when fragmentation.In order to take full advantage of the common brick powder, this research will be investigated the common brick powder and substitute the impact on high water storage type eco-concrete performance of common brick aggregate and cement.
The high water storage concrete of 5-10mm aggregate size, when aggregate all is rubble, ultimate compression strength is 9.05MPa, and when all changing waste and old fragment of brick into, ultimate compression strength is 5.77MPa, and intensity has reduced 36%.The high water storage concrete of 10-15mm particle diameter, when aggregate all is rubble, ultimate compression strength is 9.10MPa, and when all changing waste and old fragment of brick into, ultimate compression strength is 6.29MPa, and intensity has reduced 22%.Along with the increase of common brick replacement stone per-cent, high water storage concrete 28d intensity presents the trend reduced gradually, but reduce, is nonlinear relationship.When the appropriate particle size, be far smaller than rubble at broken fragment of brick while we have found that the waste and old brick intention that 5-10mm follows 10-15mm.High water storage concrete is the concrete that dry is larger, and its intensity source depends mainly on friction force between aggregate and the cohesive strength between aggregate and cement slurry, and this is consistent with pervious concrete result of study that document [11] is reported.All use the cement of same numeral in experiment, and use identical molding mode, so we think that the major cause that intensity reduces is can't as rubble, when aggregate rubs mutually, bear so large frictional force when waste and old fragment of brick is done aggregate, thereby fracture and bursting apart, cause the reduction of the upper high water storage concrete crushing strength of macroscopic view then.
3.3 the research of high water storage concrete water-intake rate
Water-intake rate refers to the water-intake rate that concrete water regain in 30min accounts for the inner effectively open pore decision of the per-cent pervious concrete of its water suction state of saturation water regain.Replace in proportion the affect result of study of crushed stone aggregate on water-intake rate from common brick, 5-10mm particle diameter and the concrete water-intake rate of the high water storage of 10-15mm particle diameter are all substantially constant along with the increase of common brick replacement per-cent or present small reduction.The maximum range of decrease is no more than 2%, shows that common brick replaces rubble and substantially can ignore for the impact of high water storage concrete water-intake rate as aggregate.
3.4 the research of high water storage concrete water-retentivity
High water storage concrete water-retentivity affect result of study: common brick replaces the impact of crushed stone aggregate on water-retentivity in proportion.Increase along with common brick replacement per-cent, the water-retentivity of pervious concrete has obvious growth, the high water storage concrete water-retentivity of 100% common brick aggregate reaches the high water storage of 100% crushed stone aggregate concrete more than 280%, reached and approached 0.2g/cm3, the high water storage concrete of 100% common brick aggregate of 1 volume can be preserved the moisture of 0.2 volume.Because common brick itself has 12%-14% saturated water-retaining capacity, and the moisture content under the crushed stone aggregate state of saturation is only 2% left and right, so common brick can utilize during as aggregate the water-retaining capacity of self to pin moisture, when concentrating rainfall, accelerate the discharge of ponding, the pressure of drainageway while reducing heavy rain; And the moisture stored when sweltering heat evaporates, can reduce again the temperature of road surface, recovered to a certain extent the effect of natural vegetation, play good environmental protection effect.Therefore, high water storage concrete is the eco-concrete of a kind of imitative vegetation well, with this high water storage concrete, builds walkway, will be one of effective method solved contradiction between China's city-building high speed development and environment protection.
3.5 the research of high water storage concrete pore rate
Porosity is one of concrete important performance characteristic of high water storage, common brick replaces rubble in proportion while doing aggregate, and the variation experimental result of porosity shows, along with the rising of common brick content, the high water storage concrete of 5-10mm particle diameter and the high water storage concrete pore of 10-15mm particle diameter rate all significantly rise.210%-220% of porosity that porosity when aggregate consists of common brick fully reaches rubble while serving as aggregate fully.Because common brick itself has than the high a lot of porosity of rubble, so the significantly difference of porosity while causing the two to serve as aggregate.
Common brick replaces rubble in proportion while doing aggregate, and the variation experimental result of porosity can also draw, the porosity that the high water storage concrete of 10-15mm particle diameter replaces point at each common brick per-cent all is greater than the high water storage concrete of 5-10mm.This is that aggregate due to large particle diameter makes internal voids increase, and it is relatively loose that test block inside becomes.
3.6 the research of high water storage agent on crack resistance of concrete freeze thawing
Waste and old common brick replaces rubble and can draw high water storage agent on crack resistance of concrete freeze thawing impact experiment, the high water storage concrete of 5-10mm particle diameter is along with the increase of common brick replacement aggregate ratio, loss of strength increases gradually, and freezing and thawing performance descends gradually, but loss of strength is substantially in 20%.The high water storage concrete of 10-15mm particle diameter is along with the increase of common brick replacement aggregate ratio, and loss of strength increases apparent in view.The maximum strength loss appears at 40% and 80% and replaces two points, and loss of strength has surpassed 30%, and freezing and thawing performance is obviously not as the 5-10mm particle diameter.
Because high water storage concrete has sizable effective porosity, its freeze-thaw damage feature generally is derived from freeze thawing and changes the inside character change brought.When freezing the time, high water storage concrete is subject to the effect of internal water pressure, and water pressure promotes water and escapes to border, and when this hydraulic pressure surpasses cement slurry tensile strength or surpassed waste and old brick intention, crack appears in inside.Concrete is subject to the freeze thawing injury.
Because the large high water storage inside concrete connectedness in aperture is poor, internal structure is relatively fine and close, and the current circulation is not smooth, and the water pressure caused is larger.And the little pervious concrete in aperture is better due to internal communication, the hydraulic pressure of generation easily dissipates, and its anti-freezing property is better than the wide aperture concrete.Therefore the high water storage agent on crack resistance of concrete of the large particle diameter of 10-15mm freeze thawing variation will obviously be worse than the high water storage concrete of 5-10mm.
3.7 the impact of brick powder on high water storage concrete strength
In experimentation, our Research team finds that the fragment of brick after fragmentation has unstable, and its surperficial flour is often easily peeled off analysis.Likely with gelling material cement, mix in preparation process, affect cement hydration process, thereby reduce high water storage concrete performance.Due in engineering, consider practical situation, be difficult to, as laboratory, experiment material is strictly shone to the attachment removal meal, tend to enter and build with some brick powder.So our Research team has designed one group of experiment, seeks the impact of brick powder content for high water storage concrete performance.
Next experiment: the 5-10mm particle diameter, common brick replaces the high water storage concrete that rubble per-cent is 40% and mixes with respect to cement quality 3%, 6%, the ultimate compression strength after 9%, 12%, 15% common brick powder (0% is contrast benchmark group).
After mixing the brick powder, decline has sharply appearred in high water storage concrete crushing strength.When incorporation reaches 6%, descend and entered the mild phase, under 6%-15% brick powder incorporation, the concrete ultimate compression strength of high water storage no longer further descends, and loss of strength amount now also approaches or has surpassed 50%.Obtain thus conclusion, the high water storage concrete strength that the brick powder is done aggregate for waste and old common brick replacement rubble has greatly infringement.To consider the impact of this respect in engineering application, carry out the screening operation of waste and old common brick aggregate.
The concrete intensity of the high water storage of macrovoid is mainly derived from the grout that is wrapped in aggregate and the cohesive strength of aggregate.The brick powder and the cement that mix mix, affected cement hydration process, make the C-S-H gel and the Aft crystal that produce in hydration process evenly not to be collected at cement particle surface, affected the strength of cement grout in the rear end length of time, thereby reduced the concrete bulk strength.Simultaneously in the cement setting phase, when cement-hydrate penetrates rete and forms osmotic pressure and cause rete to break, the brick powder is attached to film surface, has reduced the speed that rete breaks, and affects hydrated cementitious and enters acceleration period, has reduced the later stage age strength.
3.8 water-permeable and the Hardenability of the ecological pavement concrete of high water storage type
High water storage concrete permeable rate affect result of study: common brick replaces the impact of crushed stone aggregate on permeability rate.By experimental data, can be found out, along with the increase of common brick replacement crushed stone aggregate per-cent, high water storage concrete permeable rate does not show the trend of obvious increase or minimizing.When the replacement rate is less than 50%, the concrete coefficient of permeability of the high water storage of 10-15mm grating is slightly higher than the concrete coefficient of permeability of the high water storage of 5-10mm grating, after replacing percentage and being greater than 50%, coefficient of permeability does not have rule, but coefficient of permeability is high by 77% when in the 10-15mm experimental group, 100% common brick is done coarse aggregate than 0% common brick.The high water storage concrete permeable of 5-10mm particle diameter rate is reduced to the 2.17cm/s of minimum 80% replacement rate by the 2.97cm/s of the highest 60% replacement rate; The high water storage concrete permeable of 10-15mm particle diameter rate is reduced to the minimum value of the 2.04cm/s of 80% common brick aggregate by the maximum value of 100% common brick aggregate 3.93cm/s.
The water-permeable of the high water storage type eco-concrete of porous is mainly determined by inner connection and semi-connected hole (being active porosity).Increase along with common brick replacement per-cent, the reason that water-permeable descends is because the aggregate after the common brick fragmentation has easily to split, lamella and the characteristic of easily peeling off, in stirring, can occur partly to collapse to separate to split, the sliver produced mixes with remaining crushed stone aggregate and complete fragment of brick aggregate, bring local continuous multi grating effect, increased concrete compactness, then reduce connection and the semi-connected hole of inside concrete, reduced the water-permeable of common brick-high water storage type eco-concrete of rubble combined aggregate.
The high water storage type eco-concrete of 10-15mm particle diameter water-permeable replaces on point substantially all higher than 5-10mm particle diameter pervious concrete at each common brick per-cent.
This is that increase due to aggregate size makes the inside concrete hole increase, microtexture from closely knit become relatively loose, porosity increases, and porosity is the important factor that determines high water storage eco-concrete water-permeable, so water-permeable is greater than little graded aggregate pervious concrete.
The setting time of high water storage type eco-concrete directly affects the construction technology of high water storage type eco-concrete.Setting time when high water storage type eco-concrete approaches the regulation slump is in Table 6.1.This table is one of Main Basis of formulating construction technology.
Setting time when the high water storage type eco-concrete of table 3.8 approaches the regulation slump
Temperature t(℃) Setting time (h)
5≤t<1 0 2
10≤t<20 1.5
20≤t<3 0 1
30≤t<35 0.75
4, the research of high water storage type eco-concrete pavement forming technique
4.1 base treatment
Before the pervious concrete surface construction, reply basic unit makes clean, and the substrate surface after processing should be coarse, clean, without ponding, and keeps certain moisture state, should carry out interface processing in case of necessity.
4.2 stir
The stirring of high water storage type eco-concrete must adopt mechanical stirring.High water storage type eco-concrete belongs to the dry material, after the presetting period mix, should not cross long-time stop, so the configuration of stirrer capacity should be selected according to parameters such as engineering size, sequence of construction and transportation means.Stir place and also must guarantee that haulage time is no more than specialized range near high water storage type eco-concrete surface construction scene, to guarantee construction quality.The stirring place should not surpass 0.5h far from the haulage time of job location.
The proportioning of high water storage type eco-concrete is to guarantee the main critical process of its intensity, so the proportioning metering is an important Quality Control Links.Proportioning is controlled and comprised: whether sack cement should be spot-check its bag of weight accurate; Answer the water ratio in Accurate Measurement aggregate (common brick, stone etc.) before every machine-team mixing, according to the water ratio of aggregate, adjust the water consumption in the pervious concrete proportioning, by the working-yard experiment, determine the construction proportioning; The permissible error of high water storage type eco-concrete starting material (by mass), should not surpass scholar 1%.High water storage type eco-cement concrete mix-design should be applicable to slip form paver, track paver, three roll shaft units and four kinds of forms of construction work of small machine.
While adopting self-dumping mixer, the aggregate, cement, enhancing material, the admixture that prepare should be dropped in stirrer, first carry out dry mixing after 60 seconds, then, by the water measured, divide to add in stirrer for 2 ~ 3 times and mixed and stirred, churning time should be controlled at 120 ~ 300 seconds.While adopting forced mixer, should first add forced mixer to mix and stir 30 seconds in aggregate and 50% water consumption, then add cement, enhancing material, admixture to mix and stir 40 seconds, finally add the residue water consumption to mix and stir more than 50 seconds.
4.3 transportation
Transportation means must adapt to the output of stirrer.High water storage type eco-concrete mixture is from the stirrer discharging, and transportation will be noted moisturizing and anti-segregation at any time, is transported to the making place and is paved, vibrates until complete.Allow maximum duration, determined according to jelling time and construction temperature by laboratory, and should meet the regulation of table 5.1.
The high water storage type eco-concrete of table 5.1 is from discharging to building the complete permission time
Construction temperature t(℃) Allow maximum duration (h)
5≤ t <1 0 2
10 ≤t < 20 1.5
20 ≤ t <3 0 1
30 ≤ t < 35 0.75
When high water storage type eco-concrete mixture is transported to pouring location, should be able to keep the slump of homogeneity and regulation.
4.4 pave
While paving, reference line should be set.Reference line stake longitudinal pitch: straight-line segment should not be greater than 10m, and perpendicular, horizontal curve section should be encrypted layout, and guarantees that firmly the reference line pulling force should not be less than 1000N.
Template should meet: texture material is solid, it is little to be out of shape, rigidity is large; The height of template should with the concrete road surface consistency of thickness; The planimetric position of formwork erection and elevation, should meet design requirements, and separant coating is answered on the surface that template contacts with concrete; Before high water storage type eco-concrete mixture paves, the height of reply template, supporting & stablizing situation etc. check comprehensively.
While normally paving, concrete is answered vibration compacting, prevents from shaking, and owes to shake or leak and shake.When high water storage type eco-concrete mixture paves, manually evenly to pave, find planeness and drainage grade accurately.For guaranteeing high water storage type eco-concrete construction quality of pavement, paving thickness should be considered its coefficient that paves, and its coefficient of loose laying is preferably 1.1.During construction, edge has been paid special attention to intact material phenomenon, timely feed supplement to carry out artificial compacting.
4.5 compacting
High water storage type eco-concrete should adopt special-purpose low-frequency vibration compactor, or adopts plate vibrator vibration and special-purpose rolling tools roll extrusion.While vibrating with plate vibrator, avoid sustained vibration on a position to use vibrator to vibrate; While adopting special-purpose low-frequency vibration compactor compacting, should be aided with artificial feed supplement and levelling.During artificial levelling, the workmen should put on pressure-reducing shoe and be operated, and should check at any time template, if any sinking, be out of shape or becoming flexible, should correct in time.
After the compacting of high water storage type eco-concrete, should use machinery to carry out the receipts face to high water storage type eco-concrete surface layer, coordinate in case of necessity manually make real, floating.During leveling, must keep the template end face clean and tidy, seam crossing plate face is smooth.High water storage type eco-concrete mixing is built and is noted avoiding surface temperature in construction more than 40 ℃, simultaneously must not be at rainy day and winter construction.The double layer design construction, upper layer and the Sub time of laying should not be greater than 1 hour.
4.6 joint treatment
According to the needs that expand with heat and contract with cold, high water storage type eco-concrete road surface must select suitable material that expansion joint is set.
4.6.1 jointing material
Must establish expansion joint during the pervious concrete pavement construction, seam is dark identical with road surface thickness.In the contracting seam of cutting surface layer, should adopt the flexible materials joint filling, and can not adopt the material of hot-fluid, in order to avoid the material of hot-fluid is penetrated in the space of high water storage type eco-concrete.Should not, with the flexible materials (as the material of similar glass cement) of mobility, and should adopt, embed the rubber and plastic plastic material of finalizing the design.
4.6.2 seaming position
As shown in Figure 1, because of the characteristic of high water storage type eco-concrete, inconvenience during construction, often adopt little expansion joint (E.J.) to replace expansion joint in reality.On sub-surface, lay square that high water storage concrete makes as surface layer 1, conventional 5m should establish little expansion joint (E.J.) 2 together in left and right; And pasting at the place, gap the rubber-plastic foamed plastic cement that pad connects, thickness is generally 3~5mm.Usually during construction also available construction joint replace little expansion joint (E.J.), during construction, every 5m establishes rubber-plastic foamed plastic cement together in left and right.When construction length surpasses 30m, should establish the cutting expansion joint (E.J.), stitch the wide 15~20mm that is controlled at and be advisable.During highway engineering construction, every 5m should establish little expansion joint (E.J.) together in left and right, stitches wide 10~15mm; When construction length surpasses 30m, should establish the expansion joint that width is 10~15m.In construction, construction joint can replace expansion joint.
Above-described is only embodiment of the present utility model, and in scheme, the general knowledge such as known concrete structure and characteristic are not done too much description at this.Should be understood that; for a person skilled in the art, under the prerequisite that does not break away from the utility model structure, can also make some distortion and improvement; these also should be considered as protection domain of the present utility model, and these can not affect effect and practical applicability that the utility model is implemented.

Claims (2)

1. high water storage concrete road surface, comprise surface layer and basic unit, it is characterized in that, surface layer is high water storage concrete layer, and surface layer is provided with the expansion joint that the multiple tracks spacing is 4~6m, is provided with the rubber-plastic foamed plastic cement that 3~5mm is thick in expansion joint.
2. high water storage according to claim 1 concrete road surface, is characterized in that: the construction joint that described expansion joint is thickness 3~5mm.
CN2013202233011U 2013-04-27 2013-04-27 Concrete pavement with high water storage capacity Expired - Fee Related CN203319874U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN2013202233011U CN203319874U (en) 2013-04-27 2013-04-27 Concrete pavement with high water storage capacity

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN2013202233011U CN203319874U (en) 2013-04-27 2013-04-27 Concrete pavement with high water storage capacity

Publications (1)

Publication Number Publication Date
CN203319874U true CN203319874U (en) 2013-12-04

Family

ID=49659243

Family Applications (1)

Application Number Title Priority Date Filing Date
CN2013202233011U Expired - Fee Related CN203319874U (en) 2013-04-27 2013-04-27 Concrete pavement with high water storage capacity

Country Status (1)

Country Link
CN (1) CN203319874U (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106938904A (en) * 2017-04-01 2017-07-11 重庆建工住宅建设有限公司 A kind of high water storage concrete of high intensity and preparation method
CN110409450A (en) * 2019-07-03 2019-11-05 中国三峡建设管理有限公司 Improve the construction method of concrete bottom plate flatness and finish

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106938904A (en) * 2017-04-01 2017-07-11 重庆建工住宅建设有限公司 A kind of high water storage concrete of high intensity and preparation method
CN110409450A (en) * 2019-07-03 2019-11-05 中国三峡建设管理有限公司 Improve the construction method of concrete bottom plate flatness and finish

Similar Documents

Publication Publication Date Title
CN101293763B (en) Water permeable concrete and pavement construction method
CN103304250A (en) High water-storage concrete
CN102162214B (en) Construction method of pervious cement concrete
CN105256692A (en) Color and pervious concrete pavement structure and construction technology therefor
CN104404838B (en) The above railway collapsible loess subgrade substrate treating method of speed 200km
CN106294973A (en) A kind of mixing proportion design method of celluar concrete
CN103882788B (en) Based on the method for constructing roadway of the modification roller compacted concrete surface layer of enzyme soil cured substrate layer
CN105777179A (en) Macroporous polyurethane macadam mixture and manufacturing method thereof
CN107034767A (en) A kind of full pervious concrete pavement structure of regeneration aggregate and its construction method
CN108059476A (en) A kind of permeable concrete and preparation method thereof
CN106759126B (en) Construction method of side slope support drainage channel
CN112028591A (en) Construction method of vertical roadbed made of red mud-based cast-in-place lightweight soil
CN106677003A (en) Pervious concrete structure and preparation method thereof
CN102776897B (en) Wash apron anti-settling anti-cracking construction method and structure
CN203319874U (en) Concrete pavement with high water storage capacity
JP2006161335A (en) Block for paving
CN106483035A (en) A kind of assay device evaluating pervious concrete service behaviour and method
CN207244376U (en) A kind of creepage concrete compression-resistance pavement structure
CN207079446U (en) A kind of sponge municipal drainage road construction apparatus
CN111535322B (en) Distorted concrete construction method with bottom grouting
CN106706497A (en) Device and method for evaluating working performance of freshly-mixed pervious concrete
CN104631259B (en) A kind of nano lamellar material application process in cement stabilized macadam base
CN109056455A (en) A kind of sponge urban construction permeable side walk slab and method for paving
CN207133290U (en) A kind of device for determining pervious concrete service behaviour
CN111535323B (en) Full-section quasi-tertiary matching long-age roller compacted concrete construction method

Legal Events

Date Code Title Description
C14 Grant of patent or utility model
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20131204

Termination date: 20190427

CF01 Termination of patent right due to non-payment of annual fee