The primary objective of this paper was to study the mechanical properties and durability of the cement stabilized gravel by different compact method. The influence of rubber particle content on mechanical properties ...The primary objective of this paper was to study the mechanical properties and durability of the cement stabilized gravel by different compact method. The influence of rubber particle content on mechanical properties of samples was studied by compaction tests and freezing thawing recycle tests. Pore structure and fractal characteristic of mixture were analyzed quantitatively using mercury intrusion porosimetry (MIP). X-ray diffraction (XRD) was adopted to identify the composition phases. The morphology analysis in micro scale and elemental analysis of samples were carried out by scanning electron microscope (SEM). The optimum compressive strengths of rubber cement stabilized gravel (RCSG) with static compaction method and with vibratory compaction method were obtained by controlling compaction degree and vibration time, respectively. From the compaction tests, the vibratory compaction method is preferred compared with the static compaction method as better compressive strength can be improved by about 340%-360%. Besides, test results also reveal that compressive strength of samples with vibratory compaction method or static compaction method will decrease with the rubber particle bulk content increasing. The freezing thawing recycle tests indicate that freezing thawing resistance has been improved (frozen stability coefficient K has been increased from 0.89 to 0.97) by the addition of rubber particles. MIP tests show that the mean pore diameter and porosity of mixture have been increased from 70 to 250 nm and 9% to 24% respectively, with the rubber particles content increasing. Component analysis shows that the calcium silicate hydrate (CSH) is the predominant hydrate product with or without the addition of rubber particles.展开更多
In order to investigate the effect o f some factors on the unconfined compressive strength(UCS)for composite soil stabilizer-stabilized gravel soil(CSSSGS),the orthogonal test is adopted to set up the experimental sch...In order to investigate the effect o f some factors on the unconfined compressive strength(UCS)for composite soil stabilizer-stabilized gravel soil(CSSSGS),the orthogonal test is adopted to set up the experimental scheme.Three levels o f each factor armconsidered to obtain the change laws o f UCS,in which the binder dosages are8%,10%,and12%;the curing times ae7,14and21d;the gradation nae0.3,0.35and0.4;and the degrees of compaction are95%,97%,and99%.The range analysis clearly indicates that the influence degree o f the four factors on UCS is in such an order:dosage,age,gradation,and degree o f compaction.The variance analysis shows that only the composite soil stabilizer dosage can significantly affect UCS.In road construction,the examination o f composite soil stabilizer dosage and base-course maintenance should be given much more attention to obtain satisfactory base-course strength,compared w ith gradation floating and the change of degree o f compaction.展开更多
The start point in this paper is dynamic load damage caused by hydrodynamic pressure to the inside void of cement stabilized macadam base considering the affect of gradation type,testing time and cracking simulation.T...The start point in this paper is dynamic load damage caused by hydrodynamic pressure to the inside void of cement stabilized macadam base considering the affect of gradation type,testing time and cracking simulation.Then the moisture damage rule of cement stabilized macadam was investigated in the lab by using the hydrodynamic pressure simulation device and testing system.Test results shows that the cement stabilized macadam with dense framework structure has better moisture-resistant performance than mixtures with suspend-dense structure.And the strength deterioration is just one-third of origin one when crack in base is loaded by hydrodynamic pressure.展开更多
基金Funded by the National Natural Science Foundation of China(No.51008076)
文摘The primary objective of this paper was to study the mechanical properties and durability of the cement stabilized gravel by different compact method. The influence of rubber particle content on mechanical properties of samples was studied by compaction tests and freezing thawing recycle tests. Pore structure and fractal characteristic of mixture were analyzed quantitatively using mercury intrusion porosimetry (MIP). X-ray diffraction (XRD) was adopted to identify the composition phases. The morphology analysis in micro scale and elemental analysis of samples were carried out by scanning electron microscope (SEM). The optimum compressive strengths of rubber cement stabilized gravel (RCSG) with static compaction method and with vibratory compaction method were obtained by controlling compaction degree and vibration time, respectively. From the compaction tests, the vibratory compaction method is preferred compared with the static compaction method as better compressive strength can be improved by about 340%-360%. Besides, test results also reveal that compressive strength of samples with vibratory compaction method or static compaction method will decrease with the rubber particle bulk content increasing. The freezing thawing recycle tests indicate that freezing thawing resistance has been improved (frozen stability coefficient K has been increased from 0.89 to 0.97) by the addition of rubber particles. MIP tests show that the mean pore diameter and porosity of mixture have been increased from 70 to 250 nm and 9% to 24% respectively, with the rubber particles content increasing. Component analysis shows that the calcium silicate hydrate (CSH) is the predominant hydrate product with or without the addition of rubber particles.
基金The National Natural Science Foundation of China(No.51108081)
文摘In order to investigate the effect o f some factors on the unconfined compressive strength(UCS)for composite soil stabilizer-stabilized gravel soil(CSSSGS),the orthogonal test is adopted to set up the experimental scheme.Three levels o f each factor armconsidered to obtain the change laws o f UCS,in which the binder dosages are8%,10%,and12%;the curing times ae7,14and21d;the gradation nae0.3,0.35and0.4;and the degrees of compaction are95%,97%,and99%.The range analysis clearly indicates that the influence degree o f the four factors on UCS is in such an order:dosage,age,gradation,and degree o f compaction.The variance analysis shows that only the composite soil stabilizer dosage can significantly affect UCS.In road construction,the examination o f composite soil stabilizer dosage and base-course maintenance should be given much more attention to obtain satisfactory base-course strength,compared w ith gradation floating and the change of degree o f compaction.
基金Sponsored by the Guangdong Provincial Department of Transportation Science and Technology Project (Grant No. 2010-04-003)Ministry of Transportation Western Transportation Construction Science and Technology Project (Grant No. 200631881216)
文摘The start point in this paper is dynamic load damage caused by hydrodynamic pressure to the inside void of cement stabilized macadam base considering the affect of gradation type,testing time and cracking simulation.Then the moisture damage rule of cement stabilized macadam was investigated in the lab by using the hydrodynamic pressure simulation device and testing system.Test results shows that the cement stabilized macadam with dense framework structure has better moisture-resistant performance than mixtures with suspend-dense structure.And the strength deterioration is just one-third of origin one when crack in base is loaded by hydrodynamic pressure.