The purpose of this study is to comparatively evaluate the wear resistance of concretes under abrasion rates. Five concrete mix proportions of a fixed water-cement ratio of 0.45 were considered in the study, but the c...The purpose of this study is to comparatively evaluate the wear resistance of concretes under abrasion rates. Five concrete mix proportions of a fixed water-cement ratio of 0.45 were considered in the study, but the constituent materials, age of concrete and exposure contact conditions were varied. The coarse aggregate type employed in the study was crushed granite. The compressive strength and abrasion resistance of concretes were tested between at ages 7 to 70 days and 100 - 500 revolutions of abrasion wheels respectively. The study revealed that the compressive strength and abrasion resistance had the optimal performance when the coarse aggregate content was 45% and the worst performance when the fine aggregate content was 28.7% of the total weight of concrete constituents. There was a remarkable loss of concrete particles to wear between 200 revs and 300 revs of abrasion wheel contact. Concrete grade in excess of 60 N/mm2 is required to resist abrasion beyond 200 revolutions of abrasion wheel contact on concrete specimens. Concretes investigated also showed weak resistance to deep abrasion at and above 300 revolutions of abrasion wheel contact.展开更多
Surface textures had long been recognized as primary factors to provide the skid resistance on pavements; however, no measurement of skid resistance on pervious concrete pavement with various surface texture parameter...Surface textures had long been recognized as primary factors to provide the skid resistance on pavements; however, no measurement of skid resistance on pervious concrete pavement with various surface texture parameters had been made. Fractal geometry was introduced in the present work to accurately simulate transect contour curves of pervious concrete specimens through fractal interpolation. It is proved that its fractal dimension (D) can be adopted to measure the skid resistance on pervious concrete pavement, overcoming the shortcomings of both macrotexture depth (DT ) and British portable pendulum number (NBP). Combined with Fujikawa-Koike tire/road contact model, the optimization method of all surface textures was recommended for designing and constructing excellently skid-resistant and noise-absorptive pervious concrete pavement. In addition, evaluating of the abrasion process and attenuation of the surface textures on concrete pavement slabs was also the focus of this work based on accelerated abrasion test. Results show that the surface textures on pervious concrete pavement slabs is extremely durable, compared to those on conventional grooved or exposed aggregate concrete pavement slabs.展开更多
The abrasion resistance properties of rubberized concrete were comparatively studied by taking silica fume and crumb tire rubber as the additives. The abrasion tests were conducted in accordance with the Chinese stand...The abrasion resistance properties of rubberized concrete were comparatively studied by taking silica fume and crumb tire rubber as the additives. The abrasion tests were conducted in accordance with the Chinese standard test method DL/T 5150 - 2001, two recommended test methods： under water method and ring method, were used. The crumb tire rubbers with the sieve size of 8-mesh and 16-mesh were incorporated into the concrete by replacing same volume of sand and as an additive. The abrasion resistance of concrete was evaluated according to the abrasion resistance strength and the mass loss. Test results show that the addition of silica fume enhanced both compressive strength and abrasion resistance of concrete, and the addition of crumb rubber reduced the compressive strength but increased notably the abrasion resistance of the concrete. Silica fume concrete performed a better abrasion resistance than control concrete, and the rubberized concrete performed a much better abrasion resistance than silica fume concrete. The abrasion resistance of rubberized concrete increased with the increase of rubber content.展开更多
Due to the shortages of natural sands along the east coast of Australia in particular and the need to fully utilise fines produced in quarry operations, progress has been made in utilising blends of manufactured sands...Due to the shortages of natural sands along the east coast of Australia in particular and the need to fully utilise fines produced in quarry operations, progress has been made in utilising blends of manufactured sands and natural sands in concrete pavements. This paper documents some of the constraints in utilising larger proportions of manufactured sands in concrete pavements. These constraints are mainly caused by the current level of knowledge regarding the impact of manufactured sands on skid and abrasion resistance of concrete pavements. This paper presents a brief review of literature on this subject in the USA, France and UK. It also briefly documents work recently carried out in Australia by CCAA （Cement Concrete and Aggregates Australia）, referring to the skid and abrasion resistance of concrete pavements using manufactured sands. The paper concludes that there is no relationship between the free silica content and the skid resistance. With regard to the abrasion resistance, it is rather the curing conditions and the compressive strength that are more important in achieving good results.展开更多
文摘The purpose of this study is to comparatively evaluate the wear resistance of concretes under abrasion rates. Five concrete mix proportions of a fixed water-cement ratio of 0.45 were considered in the study, but the constituent materials, age of concrete and exposure contact conditions were varied. The coarse aggregate type employed in the study was crushed granite. The compressive strength and abrasion resistance of concretes were tested between at ages 7 to 70 days and 100 - 500 revolutions of abrasion wheels respectively. The study revealed that the compressive strength and abrasion resistance had the optimal performance when the coarse aggregate content was 45% and the worst performance when the fine aggregate content was 28.7% of the total weight of concrete constituents. There was a remarkable loss of concrete particles to wear between 200 revs and 300 revs of abrasion wheel contact. Concrete grade in excess of 60 N/mm2 is required to resist abrasion beyond 200 revolutions of abrasion wheel contact on concrete specimens. Concretes investigated also showed weak resistance to deep abrasion at and above 300 revolutions of abrasion wheel contact.
基金Project(kfj080205) supported by Key Laboratory of Road Structure and Material of Ministry of Transport of Changsha, China
文摘Surface textures had long been recognized as primary factors to provide the skid resistance on pavements; however, no measurement of skid resistance on pervious concrete pavement with various surface texture parameters had been made. Fractal geometry was introduced in the present work to accurately simulate transect contour curves of pervious concrete specimens through fractal interpolation. It is proved that its fractal dimension (D) can be adopted to measure the skid resistance on pervious concrete pavement, overcoming the shortcomings of both macrotexture depth (DT ) and British portable pendulum number (NBP). Combined with Fujikawa-Koike tire/road contact model, the optimization method of all surface textures was recommended for designing and constructing excellently skid-resistant and noise-absorptive pervious concrete pavement. In addition, evaluating of the abrasion process and attenuation of the surface textures on concrete pavement slabs was also the focus of this work based on accelerated abrasion test. Results show that the surface textures on pervious concrete pavement slabs is extremely durable, compared to those on conventional grooved or exposed aggregate concrete pavement slabs.
基金Funded by the National Natural Science Foundation of China(50979068)
文摘The abrasion resistance properties of rubberized concrete were comparatively studied by taking silica fume and crumb tire rubber as the additives. The abrasion tests were conducted in accordance with the Chinese standard test method DL/T 5150 - 2001, two recommended test methods： under water method and ring method, were used. The crumb tire rubbers with the sieve size of 8-mesh and 16-mesh were incorporated into the concrete by replacing same volume of sand and as an additive. The abrasion resistance of concrete was evaluated according to the abrasion resistance strength and the mass loss. Test results show that the addition of silica fume enhanced both compressive strength and abrasion resistance of concrete, and the addition of crumb rubber reduced the compressive strength but increased notably the abrasion resistance of the concrete. Silica fume concrete performed a better abrasion resistance than control concrete, and the rubberized concrete performed a much better abrasion resistance than silica fume concrete. The abrasion resistance of rubberized concrete increased with the increase of rubber content.
文摘Due to the shortages of natural sands along the east coast of Australia in particular and the need to fully utilise fines produced in quarry operations, progress has been made in utilising blends of manufactured sands and natural sands in concrete pavements. This paper documents some of the constraints in utilising larger proportions of manufactured sands in concrete pavements. These constraints are mainly caused by the current level of knowledge regarding the impact of manufactured sands on skid and abrasion resistance of concrete pavements. This paper presents a brief review of literature on this subject in the USA, France and UK. It also briefly documents work recently carried out in Australia by CCAA （Cement Concrete and Aggregates Australia）, referring to the skid and abrasion resistance of concrete pavements using manufactured sands. The paper concludes that there is no relationship between the free silica content and the skid resistance. With regard to the abrasion resistance, it is rather the curing conditions and the compressive strength that are more important in achieving good results.
