กำลังและความคงทนของดินลูกรังผสมเถ้าลอยจีโอโพลีเมอร์สำหรับบล็อกประสานไม่รับน้ำหนักStrength and Durability of Lateritic Soil Mixed with Fly Ash Geopolymer as a Non-bearing Interlocking Block

งานวิจัยนี้ศึกษากำลัง และความคงทนของดินลูกรังผสมเถ้าลอยจีโอโพลีเมอร์ โดยใช้อัตราส่วนดินลูกรังต่อเถ้าลอยเท่ากับ 3:1 อัตราส่วนโซเดียมซิลิเกต (Na2SiO3) ต่อโซเดียมไฮดรอกไซด์ (NaOH) เท่ากับ 80:20, 70:30 และ 50:50 ความเข้มข้นของ NaOH มีค่าเท่ากับ 1, 3 และ 5 โมลาร์ (M) และอายุบ่ม 7, 14, 28, 60 และ 90 วัน โดยทำการทดสอบการบดอัด กำลังอัดแกนเดียว กำลังดัด และความคงทนที่สภาวะเปียกสลับแห้งของดินลูกรังผสมเถ้าลอยจีโอโพลีเมอร์ พบว่าอัตราส่วน Na2SiO3:NaOH และความเข้มข้นของ NaOH มีผลต่อหน่วยน้ำหนักแห้ง กำลังอัดแกนเดียว กำลังดัด และความคงทนของตัวอย่าง หน่วยน้ำหนักแห้งสูงสุด และปริมาณสารกระตุ้นที่เหมาะสมของตัวอย่างมีค่าเท่ากับ 19.01 kN/m3 และร้อยละ 18 ตามลำดับ กำลังอัดและกำลังดัดสูงสุดของตัวอย่างพบที่อัตราส่วน Na2SiO3:NaOH เท่ากับ 80:20 และความเข้มข้นของ NaOH เท่ากับ 5 M ที่อายุบ่ม 28 วัน มีค่าเท่ากับ 6.55 และ 2.70 MPa ตามลำดับ ค่ากำลังอัดสูงกว่าเกณฑ์มาตราฐานประมาณ 2.62 เท่า ปริมาณ NaOH ส่งผลกระทบต่อกำลังอัด การดูดซึมน้ำ และร้อยละการสูญเสียน้ำหนักของตัวอย่าง ปริมาณ NaOH ที่สูงขึ้นสามารถชะซิลิก้าได้ดีเมื่อได้รับความร้อน ซึ่งทำให้ตัวอย่างมีความแน่นมากขึ้นThis research studies the strength and durability of lateritic soil mixed with fly ash geopolymer. The following parameters, i.e. the ratio of lateritic soil (LS) to fly ash (FA) at 3 : 1; the ratio of sodium silicate (Na2SiO3) to sodium hydroxide (NaOH) at 80 : 20, 70 : 30, and 50 : 50; the concentration of NaOH of at 1, 3 and 5 Molar (M); and curing time of 7, 14, 28, 60, and 90 days were investigated in this study. The compaction test, the unconfined compressive strength (UCS), the flexural strength (FS), and the wet–dry cycles of LS mixed with FA geopolymer were evaluated. The test results showed that Na2SiO3 : NaOH ratio and the concentration of NaOH had an effect on dry unit weight, UCS, and FS. The maximum dry unit weight and the optimum liquid alkaline content of the sample were 19.01 kN/m3 and 18% respectively. The maximum UCS and FS of the sample of Na2SiO3 : NaOH at the ratio of 80 : 20 and the concentration of NaOH of 5 Molar at 28 days curing were 6.55 and 2.70 MPa respectively. This maximum UCS was higher than the standard of non-bearing interlocking block at 2.62 times. The amount of NaOH had an effect on UCS, water absorption and weight loss of the sample. The higher NaOH content could leached silica when sample was heated, causing more dense matrix structure

Performance of Asphalt Concrete Pavement Reinforced with High-Density Polyethylene Plastic Waste

This research investigates the possibility of using high-density polyethylene (HDPE) plastic waste to improve the properties of asphalt concrete pavement. HDPE plastic waste contents of 1, 3, 5, and 7% by aggregate weight were used. HDPE plastic waste=stabilized asphalt concrete pavement (HDPE-ACP) was evaluated by performance testing for stability, indirect tensile strength, resilient modulus (MR), and indirect tensile fatigue (ITF). In addition, microstructure, pavement age, and CO2 emissions savings analyses were conducted. The performance test results of the HDPE-ACP were better than those without HDPE plastic waste. The optimum HDPE plastic waste content was 5%, offering the maximum MR, ITF, and pavement age. Scanning electron microscope images showed that the excessive HDPE plastic waste content of 7% caused a surface rupture of the sample. Improvements in the pavement age of the HDPE-ACP samples were observed compared with the samples with no HDPE plastic waste. The highest pavement age of the HDPE-ACP sample was found at an HDPE plastic waste content of 5% by aggregate weight. The CO2 emissions savings of the sample was 67.85 kg CO2-e/m3 at the optimum HDPE plastic waste content

Performance of Asphalt Concrete Pavement Reinforced with High-Density Polyethylene Plastic Waste

This research investigates the possibility of using high-density polyethylene (HDPE) plastic waste to improve the properties of asphalt concrete pavement. HDPE plastic waste contents of 1, 3, 5, and 7% by aggregate weight were used. HDPE plastic waste=stabilized asphalt concrete pavement (HDPE-ACP) was evaluated by performance testing for stability, indirect tensile strength, resilient modulus (MR), and indirect tensile fatigue (ITF). In addition, microstructure, pavement age, and CO2 emissions savings analyses were conducted. The performance test results of the HDPE-ACP were better than those without HDPE plastic waste. The optimum HDPE plastic waste content was 5%, offering the maximum MR, ITF, and pavement age. Scanning electron microscope images showed that the excessive HDPE plastic waste content of 7% caused a surface rupture of the sample. Improvements in the pavement age of the HDPE-ACP samples were observed compared with the samples with no HDPE plastic waste. The highest pavement age of the HDPE-ACP sample was found at an HDPE plastic waste content of 5% by aggregate weight. The CO2 emissions savings of the sample was 67.85 kg CO2-e/m3 at the optimum HDPE plastic waste content

Stabilization of Recycled Concrete Aggregate Using High Calcium Fly Ash Geopolymer as Pavement Base Material

This research investigated high calcium fly ash geopolymer stabilized recycled concrete aggregate (RCA-FAG) as pavement base material. The effect of recycled concrete aggregate (RCA):high calcium fly ash (FA) ratios, sodium silicate (Na2SiO3):sodium hydroxide (NaOH) ratio, and curing time on the unconfined compressive strength (UCS) and scanning electron microscope (SEM) properties of RCA-FAG samples were evaluated. The maximum dry unit weight of the RCA-FAG sample was 20.73 kN/m3 at RCA:FA ratio of 80:20 and Na2SiO3:NaOH ratio of 60:40. The 7-d UCS of RCA-FAG samples increased as the FA content and Na2SiO3:NaOH ratio increased. The 7-d UCS of the RCA-FAG sample was better than that of the RCA with no FA because FA particles filled in RCA particles, resulting in a dense matrix. The 7-d UCS of RCA-FAG samples passed the 7-d UCS requirement for the low-traffic road. All ingredients met the 7-d UCS requirement for the high-traffic road except the sample with RCA:FA of 100:0 and Na2SiO3:NaOH of 50:50 and 60:40. The 7-d SEM images indicated that spherical FA and RCA particles are bonded together, resulting in the dense matrix for all Na2SiO3:NaOH ratios. The proposed equation for predicting the UCS of RCA-FAG offered a good coefficient of correlation, which is useful in designing pavement base material from RCA-FAG material

Stabilization of Recycled Concrete Aggregate Using High Calcium Fly Ash Geopolymer as Pavement Base Material

This research investigated high calcium fly ash geopolymer stabilized recycled concrete aggregate (RCA-FAG) as pavement base material. The effect of recycled concrete aggregate (RCA):high calcium fly ash (FA) ratios, sodium silicate (Na2SiO3):sodium hydroxide (NaOH) ratio, and curing time on the unconfined compressive strength (UCS) and scanning electron microscope (SEM) properties of RCA-FAG samples were evaluated. The maximum dry unit weight of the RCA-FAG sample was 20.73 kN/m3 at RCA:FA ratio of 80:20 and Na2SiO3:NaOH ratio of 60:40. The 7-d UCS of RCA-FAG samples increased as the FA content and Na2SiO3:NaOH ratio increased. The 7-d UCS of the RCA-FAG sample was better than that of the RCA with no FA because FA particles filled in RCA particles, resulting in a dense matrix. The 7-d UCS of RCA-FAG samples passed the 7-d UCS requirement for the low-traffic road. All ingredients met the 7-d UCS requirement for the high-traffic road except the sample with RCA:FA of 100:0 and Na2SiO3:NaOH of 50:50 and 60:40. The 7-d SEM images indicated that spherical FA and RCA particles are bonded together, resulting in the dense matrix for all Na2SiO3:NaOH ratios. The proposed equation for predicting the UCS of RCA-FAG offered a good coefficient of correlation, which is useful in designing pavement base material from RCA-FAG material