Mechanical Properties of Wood Fiber Reinforced Geopolymer Composites with Sand Addition

ABSTRACT

Fly ash-based geopolymers can be considered as a greener alternative to ordinary Portland cement, featuring comparable properties and cost yet with lower CO₂ emissions. New wood fiber reinforced geopolymer composites with sand addition (WFSGC) have been synthesized at room temperature by mixing powder (fly ash, sand and randomly reinforced wood fiber) with sodium silicate and sodium hydroxide as alkaline activators. New WFSGC were cured at 90°C for 24 h. The design and investigation of WFSGC were based on a fix 5 wt.% percentage of sand, with variable wood fiber (5, 10, 15, 20, 25, 30 and 35 wt.%) and fly ash percentages. These WFSGC showed decreasing mechanical properties with increasing wood fiber addition as measured by the compressive strength at the cylindrical test (21.76–42.52 MPa), the compressive strength at the cubic test (31.79–39.17 MPa), the force load at upper yield at the cylindrical test (1.27–3.58KN), the flexural strength (7–10.76 MPa), compressive modulus at the cylindrical test (590,75–1021.17 MPa), the compressive modulus at cubic test (787.92–1059.79 MPa) and the flexural modulus (298.03–737.83 MPa). The density of WFRGC decreases with the addition of wood fiber (1.49–1.71 g/cm³). WFSGC with addition wood fibers up to 15 wt.% could be the limit for a promising green material for construction.

摘要

粉煤灰基地质聚合物可被视为普通硅酸盐水泥的绿色替代品，其性能和成本相当，但二氧化碳排放量较低. 以粉煤灰、砂和随机增强木纤维为原料，以硅酸钠和氢氧化钠为碱性激发剂，在室温下合成了新型加砂木纤维增强土工聚合物复合材料（WFSGC）. 新WFSGC在90°C下固化24小时. WFSGC的设计和调查基于固定的5wt.%的砂、可变的木纤维（5、10、15、20、25、30和35 wt.%）和飞灰百分比. WFSGC显示随着木纤维添加量的增加，机械性能下降，通过圆柱形试验（21.76-42.52MPa）的抗压强度，立方体试验中的抗压强度（31.79-39.17MPa），上部屈服时的上部屈服强度来衡量. 圆柱试验（1.27-3.58KN），弯曲强度（7-10.76MPa），圆柱试验时的压缩模量（590,75-1021.17MPa），立方试验时的压缩模量（787.92-1059.79MPa）和弯曲 模量（298.03-737.83MPa）. 随着木纤维（1.49-1.71 g/cm3）的加入，WFSGC的密度逐渐减小. WFSGC加上高达15 wt%的木材纤维可能是一种有前途的绿色建筑材料的极限.

KEYWORDS:

• Wood fiber
• fly ash
• sand
• geopolymer composites

关键词:

• 木纤维
• 粉煤灰
• 沙子
• 地质聚合物复合材料

Acknowledgments

This work was supported by the ERANet-LAC 2^nd Joint Call (http://www.eranet-lac.eu) and funded by the Romanian National Authority for Scientific Research and Innovation, CCCDI – UEFISCDI, project number ERANET- LAC-FIBER 17/2017, within PNCDI II and National Centre for Research and Development, Poland, under grant: “Development of eco-friendly composite materials based on geopolymer matrix and reinforced with waste fibers”.

Additional information

Funding

This work was supported by the ERANET- LAC [ERANET- LAC-FIBER 17/2017,National Centre for Research and Development, Pola].

Notes on contributors

Gabriel Furtos

Dr. Gabriel Furtos PhD (E-mail: [email protected]) is senior scientist in Department of Composite Materials from Raluca Ripan Institute of Research in Chemistry, Babes-Bolyai University, Cluj-Napoca, Romania. He is interested in develop and characterization new fiber reinforced cement and composites.

Laura Silaghi-Dumitrescu

Laura Silaghi-Dumitrescu PhD (E-mail: [email protected]) is scientist in Department of Composite Materials from Raluca Ripan Institute of Research in Chemistry, Babes-Bolyai University, Cluj-Napoca, Romania. She is interested in develop and characterization new cement and composites.

Petru Pascuta

Petru Pascuta PhD (E-mail: [email protected]) is associate professor at Physics and Chemistry Department, Faculty of Materials and Environmental Engineering from Technical University of Cluj-Napoca, Romania His research activities have numerous theoretical and practical results, used to develop many materials like glasses and glass ceramics doped with transition metal ions or rare earth ions with possible applications in electronics and telecommunications.

Codruta Sarosi

Codruta Sarosi PhD (E-mail: [email protected]) is scientist in Department of Composite Materials from Raluca Ripan Institute of Research in Chemistry, Babes-Bolyai University, Cluj-Napoca, Romania. She is interested in develop and characterization new cement and composites.

Kinga Korniejenko

Kinga Korniejenko PhD (E-mail: [email protected]) is a researcher at the Institute of Materials Engineering, Faculty of Mechanical Engineering, Cracow University of Technology, Poland. She received her first MS from Material Engineering and second one from Management; and PhD from Management as well as form Materials Engineering. Her research interests include durability of alkali-activated materials and geopolymers, especially fly ash based composites reinforced by short fibres for the supplication in the marine environment.