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
The behavior of L-Shaped RC (reinforced concrete) shear walls was investigated in the Erciyes University Earthquake Investigation Laboratory under the influence of constant axial load together with reversed cyclic l...The behavior of L-Shaped RC (reinforced concrete) shear walls was investigated in the Erciyes University Earthquake Investigation Laboratory under the influence of constant axial load together with reversed cyclic lateral load. The objective of this study was to evaluate the effects of cross sectional dimensions on the behavior of L-shaped structural members and to assess their earthquake performance. In order to investigate L-shaped RC structural members, the special experiment setup and four type of 1/2 scaled specimens which have different aspect ratio were constructed. The specimens were loaded in line with the major principal axes direction laterally. Axial load ratio was 0.1 and cross section height to thickness ratios were' 3:1, 5:1, 8:1, 10:1. Cross section thickness was 120 mm which corresponds to (360:120), (600:120), (960:120), (1,200:120) wall legs cross sectional dimensions in mm. The specimens height was 1,500 mm, together with upper and lower slabs overall height was 2,000 mm. Concrete compression strength was 30 N/mm2, steel yield stress 420 N/mm2 and vertical reinforcement ratio was 1% for all specimens. According to the test results, the specimen of which the aspect ratio is 3 (360:120) has shown column behavior, the specimen of which the aspect ratio is 5 (600:120) has shown slender wall behavior and last two specimens of which the aspect ratios are 8 (960:120) and 10 (1,200:120) have shown squat wall behavior. When considering the cracking patterns and hysteretic behavior, since the aspect ratio 8, the specimens show flexure-shear interaction behavior and prone to brittle failure.展开更多
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.
文摘The behavior of L-Shaped RC (reinforced concrete) shear walls was investigated in the Erciyes University Earthquake Investigation Laboratory under the influence of constant axial load together with reversed cyclic lateral load. The objective of this study was to evaluate the effects of cross sectional dimensions on the behavior of L-shaped structural members and to assess their earthquake performance. In order to investigate L-shaped RC structural members, the special experiment setup and four type of 1/2 scaled specimens which have different aspect ratio were constructed. The specimens were loaded in line with the major principal axes direction laterally. Axial load ratio was 0.1 and cross section height to thickness ratios were' 3:1, 5:1, 8:1, 10:1. Cross section thickness was 120 mm which corresponds to (360:120), (600:120), (960:120), (1,200:120) wall legs cross sectional dimensions in mm. The specimens height was 1,500 mm, together with upper and lower slabs overall height was 2,000 mm. Concrete compression strength was 30 N/mm2, steel yield stress 420 N/mm2 and vertical reinforcement ratio was 1% for all specimens. According to the test results, the specimen of which the aspect ratio is 3 (360:120) has shown column behavior, the specimen of which the aspect ratio is 5 (600:120) has shown slender wall behavior and last two specimens of which the aspect ratios are 8 (960:120) and 10 (1,200:120) have shown squat wall behavior. When considering the cracking patterns and hysteretic behavior, since the aspect ratio 8, the specimens show flexure-shear interaction behavior and prone to brittle failure.