郭乔明, 陈峰, 张育铖,等. 粉煤灰-矿渣地聚物固化长石粉路用性能研究[J].河南理工大学学报(自然科学版)，doi:10.16186/j.cnki.1673-9787.2024120060.

GUO Q M, CHEN F, ZHANG Y C, et al． Road performance of fly ash-slag geopolymer stabilized feldspar powder [J]. Journal of Henan Polytechnic University( Natural Science) ， doi: 10.16186/j.cnki.1673-9787.2024120060.

粉煤灰-矿渣地聚物固化长石粉路用性能研究(网络首发)

郭乔明¹, 陈峰¹，张育铖²，杨璐¹, 陈慧¹，赵华²，关博文³

1. 江西省交通投资集团有限责任公司, 江西 南昌 330199；2. 南昌大学 工程建设学院 江西 南昌 330031；3.长安大学 材料科学与工程学院，陕西 西安 710064

摘要: 目的 为探究长石粉在公路工程中大规模利用的可行性，实现公路工程绿色发展, 方法 使用粉煤灰和矿渣粉两种工业固废作为原材料制备地聚物胶凝材料，通过改变水玻璃模数和Na₂O质量分数调整地聚物的Si/Al和Na/Al摩尔比，探究地聚物强度的变化规律，确定地聚物配合比。使用粉煤灰-矿渣粉二元地聚物固化长石粉，以材料的无侧限抗压强度、抗剪强度、回弹模量、膨胀率、收缩率、浸水质量损失率和软化系数的试验结果综合评估其路用性能。借助X射线衍射(XRD)、傅里叶红外光谱(FTIR)以及扫面电镜(SEM)对固化长石粉进行微观表征，分析地聚物的固化机理。结果 结果表明：地聚物可以显著提高固化材料的强度和水稳性，并减小吸水膨胀和干燥收缩造成的变形；在材料中复掺土壤也可以提高强度，但水稳性会有所降低，吸水膨胀和干燥收缩产生的变形均增大。当地聚物占比为20%、长石粉占比为80%时，固化材料的28 d无侧限抗压强度为2.36 MPa，回弹模量为98.03 MPa，膨胀率为0.029%，收缩率为0.215%，浸水质量损失率小于2%，软化系数为0.81，可满足高等级公路路基的要求和二级公路中轻交通下基层和高等级公路中轻交通下底基层的相关要求。粉煤灰-矿渣基地聚物水化后产生大量无定形凝胶以及少量Ca(OH)₂、CaCO₃和长石类结晶体，这些产物使固化材料颗粒间形成良好的胶结并填充孔隙，提高了材料的密实性，使其拥有良好的路用性能。结论 本文研究结果为地聚物固化长石粉的工程应用提供理论和试验依据。

关键词: 地聚物；长石粉；公路工程；路用性能；固化机理

doi: 10.16186/j.cnki.1673-9787.2024120060

基金项目: 国家自然科学基金资助项目（52168062）；江西省交通运输厅重点工程科技项目（2023C0014）

收稿日期：2024-12-25

修回日期：2025-04-24

网络首发日期：2025-06-12

Road performance of fly ash-slag geopolymer stabilized feldspar powder (Online)

Guo Qiaoming¹, Chen Feng¹, Zhang Yucheng², Yang Lu¹, Chen Hui¹, Zhao Hua², Guan Bowen³

1. Jiang Xi Communications Investment Group Co. Ltd, Nanchang，330199,China;2.School of Infrastructure Engineering, Nanchang University, Nanchang，330031,China;3.School of material science and engineering, Chang’an University, Xi’an，710064,China

Abstract：Objectives To explore the feasibility of large-scale utilization of feldspar powder in highway engineering and promote green development in the field of road construction. Methods Fly ash and ground granulated blast-furnace slag (GGBS), two types of industrial solid waste, were used as raw materials to prepare geopolymer cementitious materials. By varying the modulus of water glass and the Na₂O mass fraction, the Si/Al and Na/Al ratios of the geopolymer were adjusted. The relationship between these factors and the strength of the geopolymer was analyzed to determine the optimal geopolymer mix proportion. Feldspar powder was stabilized using the binary geopolymer composed of fly ash and GGBS. The road performance of the stabilized material was comprehensively evaluated based on unconfined compressive strength, shear strength, resilient modulus, expansion rate, shrinkage rate, immersion mass loss rate, and softening coefficient. Additionally, the microstructure of the stabilized feldspar powder was characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) to investigate the stabilization mechanism of the geopolymer. Results The results showed that the strength and water stability of the stabilized materials were significantly enhanced by the geopolymer. Deformation caused by water absorption expansion and drying shrinkage was reduced. When soil was incorporated, the strength was increased, but water stability was decreased. Deformation caused by water absorption expansion and drying shrinkage was both increased. When the geopolymer content was 20% and the feldspar powder content was 80%, the 28 day unconfined compressive strength of the stabilized material reached 2.36 MPa. The resilient modulus was measured at 98.03 MPa. The expansion rate was 0.029%, and the shrinkage rate was 0.215%. The immersion mass loss rate was less than 2%, and the softening coefficient was 0.81. These properties met the requirements for high-grade highway subgrades, as well as light-traffic sub-base layers in secondary highways and light-traffic sub-base layers in high-grade highways. A large amount of amorphous gel was generated after the hydration of the fly ash-GGBS based geopolymer. Small amounts of Ca(OH)₂, CaCO₃, and feldspar crystalline phases were also detected. These products formed effective bonding between the particles of the stabilized material and filled the pores. The compactness of the material was enhanced, resulting in excellent road performance. Conclusions The findings of this study provided theoretical and experimental evidence for the engineering application of geopolymer-stabilized feldspar powder.

Key words: geopolymer; feldspar powder; highway engineering; road performance; curing mechanism