Chan-Yong Sung

Physical and Mechanical Properties of Porous Concrete Using Waste Activated Carbon

This study was performed to evaluate the physical and mechanical properties of concrete using waste activated carbon. Materials used were ordinary portlant cement, crushed coarse aggregate, natural fine aggregate, waste activated carbon, and superplasticizer. The substitution ratios of waste activated carbon were 0,1,2,3,4,5,6,7,8,9 and 10%. The unit weight was decreased and water absorption ratio was increased with increasing the waste activated carbon content, respectively. When the substitution ratio of waste activated carbon was 3%, compressive strength, flexural strength and dynamic modulus of elastisity were more higher than that of the ordinary portland cement (OPC), and it was decreased with increasing the waste activated carbon content, respectively. The most effective contents of waste activated carbon was 2% in performance and 4% in practical use Accordingly, waste activated carbon can be used for concrete material.

Strength and Watertightness Properties of EVA Modified High Strength Concrete

This study was performed to evaluate strength and watertightness properties of EVA modified high strength concrete in order to improve durability of concrete used in agricultural water utilization facilities that are in constant contact with water. Materials used were cement, coarse and fine aggregates, silica fume, EVA and AE water reducing agent. Tests for the slump, compressive and flexural strengths, absorption ratio and permeability coefficient according to curing condition (water and water+dry curing) and content ratio of EVA were performed. The slump results of EVA modified high strength concrete similarly showed in the content ratio of EVA powder less than 4% and decreased in the content ratio of EVA powder more than 6% compared to that of concrete without EVA powder. The compressive strength of EVA modified high strength concrete decreased with increasing the content ratio of EVA powder. The flexural strength of EVA modified high strength concrete increased with increasing the content ratio of EVA powder in the content ratio of EVA powder ratio less than 4% and had similar or slightly decreased in the content ratio of EVA powder more than 6% compared to that of concrete without EVA powder. The absorption ratio and permeability coefficient of EVA modified high strength concrete decreased with increasing the content ratio of EVA powder in the content ratio of EVA powder less than 4% and slightly increased in the content ratio of EVA powder more than 6%.

Strength and Durability Properties of Recycled Polymer Concrete Using Unsaturated Polyester Resin and Recycled Aggregates

This study was performed to evaluate the strength and durability properties of recycled polymer concrete using unsaturated polyester resin and recycled aggregates. Unsaturated polyester resin, natural and recycled aggregates and fly ash were used. The mix proportions were determined to satisfy the requirement for the workability and slump according to aggregate sizes (5-10 and 5-25 mm) and unit binder contents (10% and 12%). Tests for the compressive and flexural strength, freezing and thawing and durability for 20% sulfuric solution were performed. The compressive and flexural strength of recycled polymer concrete were in the range of 85~97 MPa and 17.9~20.8 MPa, respectively. The strengths of recycled polymer concrete using recycled aggregate have similar or slightly decreased compared to polymer concrete using natural aggregate. After 300 cycles of freezing and thawing, weight decrease ratio and durability factor of recycled polymer concrete were in the range of 0.13~1.42% and 94~99, respectively.

Experimental Study on Rainfall Runoff Reduction Effects by Permeable Polymer Block Pavement

Most of the roads are paved with impermeable materials such as asphalt concrete and cement concrete, and in the event of heavy rainfall, rainwater directly flows into river through a drainage hole on the pavement surface. This large quantity of rainwater directly spilled into the river frequently leads to the flooding of urban streams, damaging lowlands and the lower reaches of a river. In recent years there has been a great deal of ongoing research concerning water permeability and drainage in pavements. Accordingly, in this research, a porous polymer concrete was developed for permeable pavement by using unsaturated polyester resin as a binder, recycled aggregate as coarse aggregate, fly ash and blast furnace slag as filler, and its physical and mechanical properties were investigated. Also, 3 types of permeable polymer block by optimum mix design were developed and rainfall runoff reduction effects by permeability pavement using permeable polymer block were analyzed based on hydraulic experimental model. The infiltration volume, infiltration ratio, runoff initial time and runoff volume in permeability pavement with permeable polymer block of mm were evaluated for 50, 100 and 200mm/hr rainfall intensity.

Void Ratio and Strength of Porous Polymer Concrete and Initial Growth Properties within Planting Block with Binder Contents

This study was performed to evaluate the void ratio and strength of porous polymer concrete used coarse aggregates and unsaturated polyester resin to find optimum mix design of porous polymer concrete for planting block. Also, this study was performed to evaluate the planting properties of herbaceous plant and cool-season grass in porous polymer blocks based on the experimental results of porous polymer concrete to develop environmentally friendly planting blocks. Tests for the void ratio and compressive strength of porous polymer concrete were performed at the curing age 7 days. Also, kinds of plants such as Tall fescue, Perennial ryegrass, Lespedeza and Alfalfa for planting were applied to porous polymer blocks. Within 6 weeks after seed, initial germination ratio, cover view and growth length for planting blocks were estimated by various methods.

Strengths and Permeability Properties of Porous Polymer Concrete for Pavement with Different Fillers

Recently, concrete has been made porous and used for sound absorption, water permeation, vegetation and water purification according to void characteristics. Many studies are carried out on the utilization of sewage sludge, fly ash and waste concrete to reduce the environmental load. This study was performed to evaluate the void, strength, relationship between void and strength, permeability and chemical resistance properties of porous polymer concrete for pavement with different fillers. An unsaturated polyester resin was used as a binder, crushed stone and natural sand were used as an aggregate and bottom ash, fly ash and blast furnace slag were used as fillers. The mix proportions were determined to satisfy the requirement for the permeability coefficient, cm/s for general permeable cement concrete pavement in Korea. The void ratios of porous polymer concrete with fillers were in the range of . The compressive strength and flexural load of porous polymer concrete with fillers were in the range of MPa and KN, respectively. The permeability coefficients of porous polymer concrete with fillers were in the range of cm/s. At the sulfuric acid resistance, the weight reduction ratios of porous polymer concrete immersed during 8-week in 5% were in the range of .

Development of Polypropylene Fiber Reinforced Environmental Friendly Pavement Material for Farm Road

This study is performed to examine the physical and mechanical properties of eco-concrete using soil, natural coarse aggregate, excellent soil compound and polypropylene fiber. The test result shows that mass loss ratio is decreased with increasing the content of coarse aggregate and excellent soil compound. The compressive and flexural strengths are increased with increasing the content of coarse aggregate, excellent soil compound and polypropylene fiber. The coefficient of permeability is decreased with increasing the content of coarse aggregate and excellent soil compound, but it is increased in 0.2% polypropylene fiber content. The lowest coefficient of permeability is showed in cm/s. These eco-concrete can be used for farm road.

Strength and Durability Properties of Polymer Concrete Utilizing Oyster Shell Powder as a Filler

This study was performed to evaluate the workability, strengths and durability of polymer concrete using oyster shell that are reclaimed at public shore illegally or leaved on the surroundings of shore to prevent the environmental pollution. We investigated the effect of oyster shell powder (OSP) and . on the slump, compressive strength, flexural strength, acid sulfuric and freezing and thawing resistance as a filler of polymer concrete. Modified OSP obtained by crushing oyster shell (less than 0.15 mm size) consists of 60.47 wt% of and 39.5 wt% of . As a result of slump test by OSP and . contents, it is found that slump of specimen used OSP is lower than that used . and the more OSP contents are, its slump is increased. Compressive and flexural strength of polymer concrete using OSP are similar or slightly lower than that using . In acid sulfuric test for 5 % and freezing thawing test, regardless of kinds of fillers and contents are not found fatal defects in weight change, falling-off in surface and durability factor.

Mechanical Properties of Permeable Polymer Concrete for Permeability Pavement with Recycled Aggregate and Fiber Volume Fraction

Research on permeable pavement like asphalt and concrete pavement with porous structure has been increasing due to environmental and functional need such as reduction of run off and flood, and increase and purification of underwater resource. This study was performed to evaluate permeability, strengths and durability of permeable polymer concrete (PPC) using recycled aggregate that is obtained from waste concrete. Also, 6mm length of polypropylene fiber was used to increase toughness and interlocking between aggregate and aggregate surrounded by binder. In the test results, regardless of kinds of aggregates and fiber contents, the compressive strength and permeability coefficient of all types of PPC showed the higher than the criterion of porous concrete that is used in permeable pavement in Korea. Also, strengths of PPC with increase polypropylene fiber volume fraction showed slightly increased tendency due to increase binder with increase of fiber volume fraction. The weight reduction ratios for PPC after 300 cycles of freezing and thawing were in the range of 1.6~3.8 % and 2.2~5.6 %, respectively. The weight change ratio was very low regardless of the fiber volume fraction and aggregates. The weight reduction ratios of PPC with fiber and aggregate were in the range of 1.3~2.7 % and 2.2~3.2 % after 13 weeks and was very low regardless of the fiber volume fraction and aggregates.

Hydration, Strength and pH Properties of Porous Concrete Using Rice Husk Ash

This study was performed to evaluate void ratio, compressive and flexural strengths, and pH properties according to the content ratio of rice husk ash, aggregate size, and neutral treatment time of porous concrete with content of rice husk ash produced as an agricultural by-product. The SEM results for cement mortar with a 5% rice husk ash for the weight of cement formed more C-S-H hydrates due to the of rice husk ash. In the XRD test, cement mortar with a 5% rice husk ash for the weight of cement registered a higher peak point of approximately