Effect of rubber particles on cement stabilized gravel system

Abstract

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.

Keywords

pavement / rubber cement stabilized gravel / mechanical property / SEM / MIP

References

[1] Sun Z, Xu Z, Wu M Study on Gradation Composition Design of Cement-stabilized Macadam Considering Shrinkage Deformation Factors[J]. Journal of Highway and Transportation Research and Development, 2006, 23(3): 15-19.

[2] Li Q, Zhang P, Shen J Research on Crack Resistance of Cement Stabilized Macadam Reinforced with Polypropylene Fiber[J]. Journal of Building Materials, 2008, 11(3): 368-374.

[3] Li M Study on Vibrating Test Methods for Cement Stabilization of Crushed Aggregate [R], 2009 Xi’an Chang’an University

[4] Siddique R, Naik T R Properties of Concrete Containing Scrap-tire Rubber: An Overview[J]. Waste Management, 2004, 24(6): 563-569.

[5] Fattuhi N I, Clark L A Cement-based Materials Containing Shredded Scrap Truck Tire Rubber [J]. Construction Building Materials, 1996, 10(4): 229-236.

[6] Bignozzi M C, Sandrolini F Tyre Rubber Waste Recycling in Selfcompacting Concrete[J]. Cement and Concrete Research, 2006 735-739.

[7] Luo Q Research on the Physico-mechanical Properties and Durability of Crumb Rubber-modified Concrete[D], 2007 Nanchang Nanchang University

[8] He Y Research on the Characteristics of the Cement Stabilized Macadam with Waste Rubber Particles[D], 2007 Nanjing Nanjing Forestry University

[9] Yang L Exploration on Microstructure and Structural Theory of Crumb Rubber Concrete[D], 2010 Tianjin Tianjin University

[10] Zhang Y, Zhao Z, Chen S, . Impact of Rubber Powder on Frost Resistance of Concrete in Water and NaCl Solution[J]. Journal of Southeast University (Natural Science Edition), 2006, 36: 248-252.

[11] Yang N, Yue W Handbook of a Collection of Illustrative Plates of Inorganic Nonmetal Materials[M], 2000 Wuhan Wuhan University of Technology Publishing Company