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1.
YANG Xi wu 《保鲜与加工》2008,(4):136-140
To prevent asphalt pavement from cracking under low temperatures and prolong its fatigue life, we tested the properties of a new type of steel fiber asphalt pavement. The tests evaluated Marshall stability, dynamic ruts, and cleavage strength under both low and normal temperature conditions. We also analyzed the anti-corrosion property of steel fiber and the factors affecting the properties of the steel fiber asphalt mixture. The steel fiber asphalt pavement was installed on a highway in Chongqing, P. R. China to investigate the construction art of the steel fiber asphalt mixture and examine its effect in field use. The test results and concrete use in the field show that the cleavage strength and flexibility of steel fiber asphalt concrete increase due to the action of steel fiber. We conclude that the anti-cracking capacity of asphalt pavement under low temperature conditions can be improved by steel fiber. The construction art of steel fiber asphalt pavement is the same as common asphalt pavement without the necessity of anti-corrosion processing for steel fiber. The research results are useful for pavement material selection in low temperature regions and heavy traffic road pavement designs. 相似文献
2.
AH-70 road asphalt as the basis, Buton rock asphalt mixture pavement performance was studied by using six different Buton rock asphalt adding quality and six different AC20 aggregate gradation. The results show that Buton rock asphalt raw materials including the rock mineral significantly affects aggregate gradation and the pavement performance; reasonable choice OAC can significantly improve the road performance, and the road performance in the condition of 0.7%~1.3% optimum OAC is close to that of the SBS modified asphalt mixture, but Buton rock asphalt improving the water stability is limited; Buton rock asphalt optimum dosage is 23.7%, and Buton rock asphalt OAC and OAC of Buton rock asphalt raw material is almost the same. 相似文献
3.
To improve the performance of asphalt rubber mixture under high temperature, an optimal proposal was put forward which selected asphalt rubber mortar and aggregate gradation as the main objects. According to experimental tests, the anti rutting factors and phase angles of asphalt mortar was studied with different rations of filler bitumen. And then, with the characteristics of asphalt rubber, the optimal gradation was presented by means of the adjustment of aggregate gradation which chose dynamic stability and relative deformation as value indexes. The results shew that asphalt rubber mixtures would show an optimal high temperature performance if the following measures can be taken: (1) making an adjustment of ratio of filler bitumen to about 1.2; (2) replacing mineral powder with cement; (3) making an adjustment of aggregate gradation and lower the proportion of mineral powder based on SMA. 相似文献
4.
Asphalt mixtures with high shear strength have great capability to resist perpetual deformation under high temperatures. We used a single penetration test to analyze the material design indexes for high performance asphalt mixtures. The test results show that the performance of the asphalt binder and the performance of the coarse aggregate, especially the fine aggregate, greatly affect the shear strength of asphalt mixtures. We also suggest that the coarse aggregate with a high aggregate particle index, fine aggregate with high angularity, and asphalt with high viscosity can increase sharply the shear strength of an asphalt mixture. Furthermore, the degree of compaction of an asphalt mixture should be controlled to guarantee excellent long term performance of asphalt pavement. 相似文献
5.
Aiming at the influence of mastics to aggregate adhesion on the performances of asphalt mixtures, three modeling techniques were adopted to prepare composite asphalt mixtures specimens. The influences of silane coupling agent on their road performances were studied and coupling mechanism was analyzed with Infrared Spectroscopy (IR) and Scanning Electron Microscope (SEM). The results indicated that the road performances at 7 day and 28 day curing age increased in the beginning and then decreased with the increase of silane coupling agent dosages. The road performances, such as freeze thaw splitting strength ratio, Marshall stability and compression modulus would be enhanced 10%~30% at 0.6% in asphalt emulsion mass. There was Si O Si chemical bond on interface between mastics and modified granite aggregate by Si O chemical bond of silane coupling agent. Surface of cement asphalt emulsion mastics was rough and its structure was dense. The cement asphalt emulsion mastics can be adhered to granite aggregate surface and mastics to aggregate interface structure is improved with silane coupling agent addition. 相似文献
6.
The shock and wearing resistances and anti-crack performance of concrete blended with polycarboxylate superplasticizer and polypropylene fiber were studied.Results show that,compared with concrete added with silica fume,the high water-reducing effect of polycarboxylate superplasticizer and fly ash reduced the consumption of cementitious material and the amount of cracks decreased significantly.Together with the action of polypropylene fiber,the shock and wearing resistances and anti-crack performance of concrete enhanced remarkably. 相似文献
7.
Study of Cracks on Rubber Concrete Beams Based on Fractal Theory 总被引：2，自引：0，他引：2
The flexural performances of a rubber concrete beam and a ordinary concrete beam are studied under concentrated load through the experiment. The influences of the content of the rubber powder in the rubber concrete beam on the bearing capacity and the crack width of beams are analyzed. The experimental results show that the crack distributions on two beam surfaces possess the characteristics of self-similar in statistical sense. The maximum crack width of the rubber concrete beam is less than that of the ordinary concrete beam under the same load level. The performance of anti-crack of the concrete beam is improved by adding the crumb rubber. Using the fractal theory, the fractal dimension values of the surface crack of the beams under different load grades are calculated and the relationship between the fractal dimension and the maximum crack width of the surface cracks is established. 相似文献
8.
In the study on the CRCP+AC composite pavement, the form and distribution pattern of cracks are two important factors influencing the performance and the lifetime of the pavement. The concrete damaged plasticity material model incorporated in the general purpose finite element software named ABAUQS was adopted to describe the mechanical characteristics of the CRC slab. Combining with the temperature field database drawn from the three-dimensional transient heat transfer analysis, the structural damage under the condition of temperature changing is analyzed. The structural damage evolution and the crack behavior of the CRC slab subjected to the thermal-mechanical coupling condition are further analyzed, which suggests that the role of the asphalt concrete surface is not confined only to the scope of improving the performance of the road, its capacity for improving the stress state of CRCP slab is worthwhile to be affirmed. And the reasonable thickness of AC layer should be designed in consideration of the thermal contraction and damage properties of the CRC slab comprehensively. 相似文献
9.
Anti stripping is an important objective of asphalt concrete engineering.Effects of acidic and alkaline fillers on anti stripping of asphalt concrete, and the possibilities of solid powder wastes added into asphalt concrete as the filler, have been explored. The result shows that additions of alkaline filler such as limestone and EF material into asphalt concrete as the filler, compared to acidic fillers such as siliceous mineral filler and fly ash, can effectively enhance the Marshell stability, resilient modulus and split tensile strength for this mixture. Meanwhile, the anti-stripping ability of asphalt concrete would be greatly improved. 相似文献
10.
The rut resistance properties of large stone flexible bases are studied, taking into consideration heavy loads and using computer simulation and numerous indoor tests. In computer simulations of large stone flexible bases, a calculation method was formulated for predicting asphalt pavement rut under dynamic loads. The method was based on the coupling of vehicle dynamic loads and pavement surface unevenness. The results of indoor testing and three dimensional numeric calculation under dynamic loads are confirmed by tracking observation results of a test road. We conclude that the rut resistance properties of large stone flexible base asphalt pavement built using low grade asphalt and low crush value high performance aggregate with reasonable gradation is no worse than that of the semirigid base asphalt pavement, and that ruts mainly are caused by the lateral shear. 相似文献
11.
The frost resistance of steel fiber reinforced concrete (SFRC) was studied based on the fast freeze thaw tests in water and in a 3.5% sodium chloride solution, with different mass fraction of steel fiber in concrete at 0%, 0.5%, 1.0%, 1.5% and 2.0%, respectively. The effects of the number of freeze thaw cycles and the volume fraction of steel fiber on the mass lose rate, the splitting strength loss rate and the dynamic modulus of elasticity of SFRC were analyzed. The reinforcement mechanism of the steel fiber under the action of freeze and thaw was also discussed. Moreover, mercury intrusion method and SEM analysis were carried out to study the pore size distribution features and the performance of microstructure on the impact of frost resistance of SFRC. The results show that adding an appropriate amount of steel fiber into concrete can reduce the pore porosity and improve the compactness of concrete. Furthermore, the presence of steel fiber proves to shrink the porosity and improve evidently the frost resistance of concrete. It is also shown that the steel fiber content has a great influence on the frost resisting property of SFRC. The best performance of SFRC can be achieved when the volume fraction of steel fiber is 1.5%. 相似文献
12.
Asphalt mortar is an important component of gussasphalt mixture, a mixture of asphalt and mineral filler. Five filler-asphalt ratios are used. The high and low temperature performance changes of gussasphalt mortars with different filler-asphalt 相似文献
13.
Experiments on the asphalt fume suppression agents and properties of asphalt concrete with fume suppression agent 
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下载免费PDF全文 Through lots of screening tests, two fume suppression agents, i.e. SBS and nanometer CaCO3, which can reduce the asphalt fume without affecting the properties of asphalt, are screened from seven additives. The best ratio of two agents for suppressing fume is presented by contrast tests of fume suppression effect, and the fume can be reduced about 30%. The properties of asphalt concrete with fume suppression agents and the mechanism of SBS and nanometer CaCO3 reducing the asphalt fume are investigated. The research findings are useful for reducing the asphalt fume in bad ventilation condition of channel pavement and urban road pavement construction. 相似文献
14.
The fatigue resistance of Gussasphalt mixture was analyzed with energy method after four point flexural fatigue test under multiple strain levels. Through the fatigue test under multiple strain levels, the linear relationship was obtained between fatigue life and cumulative dissipated energy in log log plot. And the equation for fatigue life prediction under different strain levels was also regressed. Besides, the relation between fatigue damage and dissipated energy of Gussasphalt mixture was analyzed with Maxwell model. And with the conceptions of hysteresis loop and phase angle, it is found that the mixture with bigger phase angle has better fatigue resistance. 相似文献
15.
Phase change material modified asphalt is prepared by using PEG/activated carbon composite solid-solid phase change materials for asphalt modification. Phase change materials modified asphalt with different ratios are aged and treaded alterably at high or low temperature, and then its appearance is observed. The properties of the modified asphalt, such as ductility, softening point, etc., are tested by using electronic tensile testing machine and thermal mechanical analyzer. Experiments show that when the content of PEG/activated carbon phase change material is 20%, the ductility of modified asphalt is the best; when the content of phase change material is 15% to 20%, the softening point of modified asphalt is obviously improved. 相似文献
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Preparation technology of fiber toughened self compacting high strength concrete was tested by measuring influence of water/binder ratio, sand percentage, and steel fiber content on spread, T500 time , U shape value, and L shape value of fresh concrete. Mechanical properties were analyzed in case of different water/binder ratio, sand percentage, and steel fiber content. The test results show that suitable W/B and sand percentage were necessary to satisfy self compacting performance of the fresh concrete. With the increase of steel fiber content, the compressive strength and flexural strength were improved while workability of fresh concrete was cut down. Steel fiber toughened self compacting high strength concrete was prepared successfully with a strength grade of CF90 and a flexural strength of more than 11.0 MPa. 相似文献
18.
Cementation Effect with Cement during Cold In Place Recycling System of Asphalt Pavement 总被引：1，自引：0，他引：1
Different kinds of structures of RAP and different contents of cement were prepared. By means of standard compaction test, unconfined compressive strength, water stability, modulus and SEM test, the cementation effect with cement was studied. It was shown that the maximum dry density of RAP mixture rose from 1.91g/cm3 to 2.00g/cm3 with the increase of cement content when A/S was 0.4. The maximum dry density of RAP mixture would rise when adding more asphalt. The unconfined compressive strength rose from 1.48MPa to 2.63 MPa and then down to 2.28MPa when cement content was 6%. The best property could be got when A/S was 0.4 and the cement content was 6% with 9.5% water. The compressive strength of RAP mixture declined after it was cured in water for 24 h, but it had the same tendency with those of which had not been maintained in water. And it is also found that RAP does not obtain better stabilities in high temperature with modular test. From SEM test, it is shown that ettringite and C S H interlace and form the netted structure, and the aggregate would be enwrapped to increase the strength. 相似文献
19.
When paving SMA asphalt road surface, the temperature factor must be thought over which infects life-span of road surface. Winter and summer temperature distribution on a steel box girder bridge is simulated, compared with data measured on EGongYan Bridge in Chongqing and HaiCang Bridge in Xiamen. A change range of high road surface design temperature suit to China is given. 相似文献
20.
LU Zheng-lan~ YANG Chun-lan~ DONG Rui-kun~ SUN Li-jun~ istry of Education Shanghai P.R.Chin .College of Civil Engineering Chongqing University Chongqing P.R.Chin 《保鲜与加工》2004,(6):49-52
The temperature of hot asphalt mixture and environment has a significant effect on the quality of asphalt pavement while paving.Influenced by various kinds of factors, the temperature of the hot asphalt mixture and environment are complicate and changeable while paving.The temperature of different space and time around asphalt pavement are measured while paving hot asphalt mixture on Hou-Yun expressway.The space-time distribution characteristics of temperature field while paving through analysis are given. 相似文献