aggregates or hydraulic cement that is used as an ingredient of concrete or mortar, and is added to the batch immediately before or during mixing. A material such as a grinding aid added to cement during its manufacture is termed an additive [1]. Superplasticizer is a type of water reducers; however, the difference between superplasticizer and water reducer is that superplasticizer will significantly reduce the water required for concrete mixing [2].
Superplasticizer is a type of water reducers; however, the difference between superplasticizer and water reducer is that superplasticizer will significantly reduce the water required for concrete mixing [3]. Generally, there are four main categories of superplasticizer: sulfonated melamine- formaldehyde condensates, sulfonated naphthalene- formaldehyde condenses, modified lignosulfonates and others such as sulfonic- acid esters and carbohydrate esters. Effects of superplasticizer are obvious, i.e., to produce concrete with a very high workability or concrete with a very high strength. Mechanism of superplasticizer is through giving the cement particles highly negative charge so that they repel each other due to the same electrostatic charge. By deflocculating the cement particles, more water is provided for concrete mixing [3]. For general usage, dosage of superplasticizer is between 1- 3 l/m3. However, the dosage can be increased to as high as 5- 20 l/m3
International Journal of Advanced Science and Technology
In engineering٫ materials are employed to design and build structures, develop and produce
new products. Recent developments are focused on producing composite and polymeric materials. Composite materials are made up of two or more separate materials combined in macroscopic structural units (or through physical change). Many materials that have two or more constituents٫ such as metallic alloys and polymer blends٫ are not composites٫ as the
structural unit is formed at the microscopic (or through chemical change) rather than macroscopic level. Examples of composite materials are straw brick٫ paper٫ reinforced
concrete٫ wood٫ and polymers reinforced with graphite (carbon) or glass fibers. Whereas,
polymeric materials are those, which belong to a group of carbon-containing (organic) materials٫ natural or manmade٫ that have macromolecular structure: very large molecules
made up of repeating molecular units. Examples of these are timber٫ rubber٫ polyethylene٫
polyester٫ polyvinyl chloride٫ wool٫ cotton٫ silk, starch and cellulose. Most polymers are
plastic, which means that they can be easily bent into different shapes.
However٫ these materials can still be improved by adding other materials to further modify
its property, which are called admixtures. An admixture of concrete is a material other than water, aggregates, cement, and fiber, added to plastic concrete or mortar to change one or more of its properties at the fresh or hardened stages [4]. Admixtures are introduced before, during, or (in some cases) after the mixing of the major ingredients. Admixtures are generally divided into two groups: chemical admixtures and mineral admixtures [5]. Chemical admixtures used in concrete generally serve as water reducers, accelerators, set retarders, or a combination. ASTM C494, “Standard Specification for Chemical Admixtures for Concrete,” contains classifications shown in Appendix A [5]. High-range admixtures reduce the amount of water needed to produce a concrete of a specific consistency by 12% or more. One potential admixture being used today is superplasticizer. Superplasticizers are high-range water-reducing admixtures that meet the requirements of ASTM C494 Type F or G [5] (refer to Appendix A). They are often used to achieve high-strength concrete from mixes with a low water-cement ratio with good workability and low segregation.
This research covers the experimentation of adding polymer fiber into the concrete mix before mixing. Mix proportion used was with respect to the cement’s percent by weight in kg being an admixture only. The experiment consists of eighteen specimens: five experimental groups with varying proportions of polymer fiber to cement and a standard mix having no polymer fiber, each being poured and molded in three cylinders for different curing ages. Testing the specimens is classified according to the curing age of the concrete as on the seventh, fourteenth and twenty-eighth days.
2. Literature
aggregates or hydraulic cement that is used as an ingredient of concrete or mortar, and is added to the batch immediately before or during mixing. A material such as a grinding aid added to cement during its manufacture is termed an additive [1]. Superplasticizer is a type of water reducers; however, the difference between superplasticizer and water reducer is that superplasticizer will significantly reduce the water required for concrete mixing [2].Superplasticizer is a type of water reducers; however, the difference between superplasticizer and water reducer is that superplasticizer will significantly reduce the water required for concrete mixing [3]. Generally, there are four main categories of superplasticizer: sulfonated melamine- formaldehyde condensates, sulfonated naphthalene- formaldehyde condenses, modified lignosulfonates and others such as sulfonic- acid esters and carbohydrate esters. Effects of superplasticizer are obvious, i.e., to produce concrete with a very high workability or concrete with a very high strength. Mechanism of superplasticizer is through giving the cement particles highly negative charge so that they repel each other due to the same electrostatic charge. By deflocculating the cement particles, more water is provided for concrete mixing [3]. For general usage, dosage of superplasticizer is between 1- 3 l/m3. However, the dosage can be increased to as high as 5- 20 l/m3International Journal of Advanced Science and TechnologyIn engineering٫ materials are employed to design and build structures, develop and producenew products. Recent developments are focused on producing composite and polymeric materials. Composite materials are made up of two or more separate materials combined in macroscopic structural units (or through physical change). Many materials that have two or more constituents٫ such as metallic alloys and polymer blends٫ are not composites٫ as thestructural unit is formed at the microscopic (or through chemical change) rather than macroscopic level. Examples of composite materials are straw brick٫ paper٫ reinforcedconcrete٫ wood٫ and polymers reinforced with graphite (carbon) or glass fibers. Whereas,polymeric materials are those, which belong to a group of carbon-containing (organic) materials٫ natural or manmade٫ that have macromolecular structure: very large moleculesmade up of repeating molecular units. Examples of these are timber٫ rubber٫ polyethylene٫polyester٫ polyvinyl chloride٫ wool٫ cotton٫ silk, starch and cellulose. Most polymers areplastic, which means that they can be easily bent into different shapes.However٫ these materials can still be improved by adding other materials to further modifyคุณสมบัติ ซึ่งเรียกว่าผสม การผลิตคอนกรีตเป็นวัสดุน้ำ ผล ซีเมนต์ และ ไฟเบอร์ เพิ่มพลาสติกคอนกรีตหรือปูนเปลี่ยนอย่างน้อยหนึ่งคุณสมบัติขั้นสด หรือเสริม [4] น้ำยาผสมจะนำก่อน ระหว่าง หรือ (ในบางกรณี) หลังจากการผสมของวัตถุดิบที่สำคัญ น้ำยาผสมปูนทรายทั่วไปแบ่งออกเป็นสองกลุ่ม: น้ำยาผสมเคมีและน้ำยาผสมแร่ [5] น้ำยาผสมเคมีที่ใช้ในคอนกรีตโดยทั่วไปทำหน้าที่ เป็นน้ำ reducers เร่ง retarders ชุด ชุด มาตรฐาน ASTM C494 "มาตรฐานข้อมูลจำเพาะสำหรับสารเคมีผสมในคอนกรีต ประกอบด้วยการจัดประเภทที่แสดงในภาคผนวก [5] ผสมน้ำยาผสมปูนทรายลดปริมาณของน้ำที่จำเป็นในการผลิตคอนกรีตของความสอดคล้องเฉพาะ 12% หรือมากกว่า หนึ่งผลิตอาจใช้วันนี้เป็น superplasticizer Superplasticizers จะสูงช่วงลดน้ำผสมที่ตรงกับความต้องการของมาตรฐาน ASTM C494 ชนิด F หรือ G [5] (ดูภาคผนวก A) นอกจากนี้พวกเขามักจะใช้เพื่อให้คอนกรีตแข็งแรงสูงจากการออกแบบผสมผสานด้วยอัตราส่วนปูนซีเมนต์น้ำต่ำง่ายและการแบ่งแยกต่ำงานวิจัยนี้ครอบคลุมถึงการทดลองเพิ่มเส้นใยพอลิเมอร์เป็นส่วนผสมคอนกรีตก่อนผสม สัดส่วนผสมที่ใช้กับเปอร์เซ็นต์ของปูนซีเมนต์โดยน้ำหนักกิโลกรัมกำลังการผลิตเท่านั้น ทดลองประกอบด้วยสิบแปด specimens: 5 กลุ่มทดลอง ด้วยสัดส่วนที่แตกต่างกันของพอลิเมอร์เส้นใยซีเมนต์และมาตรฐานผสมมีใยพอลิเมอร์ไม่ แต่ละ poured และแม่พิมพ์ในถังสามสำหรับบ่มผิววัยแตกต่างกัน ทดสอบไว้เป็นตัวอย่างถูกจัดประเภทตามอายุบ่มผิวคอนกรีตตามวันเจ็ด จวน และยี่สิบแปด2. เอกสารประกอบการ
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