In this research, sulfur was modified as an additive, which is applicable to normal portland cement concrete mixture, in order to use it as a road pavement material. DCPD was used as a modifier and pyridine was used to give it hydrophilic property. Before being used as a road pavement material, an a...
In this research, sulfur was modified as an additive, which is applicable to normal portland cement concrete mixture, in order to use it as a road pavement material. DCPD was used as a modifier and pyridine was used to give it hydrophilic property. Before being used as a road pavement material, an appropriate amount of modified sulfur should be calculated. Therefore, by testing compressive strength and flexural strength of mortar, its appropriate amount was selected. And its amount considered appropriate when it showed similar or higher strength, compared to that of normal mortar. The test results also showed that the more modified sulfur was added, the lesser was its strength level. But when modified sulfur was added at 3% and 5%, it showed similar or higher strength level, compared to those of normal portland cement concrete mixture. Therefore, the appropriate amount of modified sulfur for concrete mixture was 3% and 5%. When modified sulfur concrete was tested, its slump and air volume were under 60 mm and 5.5±1.5%, which meet the standards of materials for cement concrete pavement. As for concrete hardening, as the amount of modified sulfur increased, final setting time tended to be faster up to three hours than that of normal portland cement concrete. As for mechanical properties such as compressive strength, modulus of elasticity, flexural strength, and splitting bond stress, as the amount of modified sulfur increased, its strength was similar or became a little higher. Especially, compressive strength was improved by air volume, slump, and aggregate grading. And its flexural strength was over 4.5MPa, which meets the standards of road structures. When a drying and contraction test was carried out, the more modified sulfur was added, the more contraction occurred, up to 0.02%. As for abrasion resistance, according to the amount of modified sulfur, the depth of abrasion was 0.16∼0.43 mm, which is much better than the standards of specification. As for the durability of MSCC, its sulfuric acid resistance, carbonation resistance, and chloride penetration resistance became higher as the amount of modified sulfur increased. Especially, when 5% modified sulfur was added, carbonation resistance became higher up to 31% and chloride penetration resistance was up to 71%. Under the condition of deicing agents (NaCl, CaCl2) and sulfate (Na2SO4, MgSO4) being soaked, freezing and thawing of concrete were tested. And the results proved that when a series of Na+ were used as base solution, freezing and thawing resistance was the lowest. But water and magnesium sulfate were used, the resistance was the highest. According to the condition of base solution, as the amount of modified sulfur increased, its freezing and thawing resistance became bigger up to 50%, compared to that of normal portland cement concrete. A scaling resistance test with naked eye showed that the efficiency of modified sulfur tended to be overvalued. Thus, a more specific test method should be needed. In addition, like freezing and thawing resistance, a series of Na+ solution directly affected scaling of concrete. And when modified sulfur was added, scaling resistance tended to increase. In order to improve scaling resistance, at least 3% modified sulfur should be added. When quality area index of MSCC on flexural strength, carbonation resistance, sulfuric acid resistance, and freezing and thawing resistance was calculated, as the amount of modified sulfur increased, its quality area index also increased up to 54%, and the bigger was W/C rate, the larger was its quality area index. With this index, MSCC was proved as a good pavement material, which has excellent mechanical properties, durability, and frost resistance.
In this research, sulfur was modified as an additive, which is applicable to normal portland cement concrete mixture, in order to use it as a road pavement material. DCPD was used as a modifier and pyridine was used to give it hydrophilic property. Before being used as a road pavement material, an appropriate amount of modified sulfur should be calculated. Therefore, by testing compressive strength and flexural strength of mortar, its appropriate amount was selected. And its amount considered appropriate when it showed similar or higher strength, compared to that of normal mortar. The test results also showed that the more modified sulfur was added, the lesser was its strength level. But when modified sulfur was added at 3% and 5%, it showed similar or higher strength level, compared to those of normal portland cement concrete mixture. Therefore, the appropriate amount of modified sulfur for concrete mixture was 3% and 5%. When modified sulfur concrete was tested, its slump and air volume were under 60 mm and 5.5±1.5%, which meet the standards of materials for cement concrete pavement. As for concrete hardening, as the amount of modified sulfur increased, final setting time tended to be faster up to three hours than that of normal portland cement concrete. As for mechanical properties such as compressive strength, modulus of elasticity, flexural strength, and splitting bond stress, as the amount of modified sulfur increased, its strength was similar or became a little higher. Especially, compressive strength was improved by air volume, slump, and aggregate grading. And its flexural strength was over 4.5MPa, which meets the standards of road structures. When a drying and contraction test was carried out, the more modified sulfur was added, the more contraction occurred, up to 0.02%. As for abrasion resistance, according to the amount of modified sulfur, the depth of abrasion was 0.16∼0.43 mm, which is much better than the standards of specification. As for the durability of MSCC, its sulfuric acid resistance, carbonation resistance, and chloride penetration resistance became higher as the amount of modified sulfur increased. Especially, when 5% modified sulfur was added, carbonation resistance became higher up to 31% and chloride penetration resistance was up to 71%. Under the condition of deicing agents (NaCl, CaCl2) and sulfate (Na2SO4, MgSO4) being soaked, freezing and thawing of concrete were tested. And the results proved that when a series of Na+ were used as base solution, freezing and thawing resistance was the lowest. But water and magnesium sulfate were used, the resistance was the highest. According to the condition of base solution, as the amount of modified sulfur increased, its freezing and thawing resistance became bigger up to 50%, compared to that of normal portland cement concrete. A scaling resistance test with naked eye showed that the efficiency of modified sulfur tended to be overvalued. Thus, a more specific test method should be needed. In addition, like freezing and thawing resistance, a series of Na+ solution directly affected scaling of concrete. And when modified sulfur was added, scaling resistance tended to increase. In order to improve scaling resistance, at least 3% modified sulfur should be added. When quality area index of MSCC on flexural strength, carbonation resistance, sulfuric acid resistance, and freezing and thawing resistance was calculated, as the amount of modified sulfur increased, its quality area index also increased up to 54%, and the bigger was W/C rate, the larger was its quality area index. With this index, MSCC was proved as a good pavement material, which has excellent mechanical properties, durability, and frost resistance.
주제어
#유황 콘크리트 도로포장 내구성
※ AI-Helper는 부적절한 답변을 할 수 있습니다.