砒砂岩抑胀固化改性机理及改性材料性能研究

Pisha sandstone is a kind of specific mudstone/sandstone, it is hard when it is dry but would collapse when immersed in water, Pisha sandstone was the main source of coarse sediment into the Yellow river. In this work, the expansion inhibition and solidification modified mechanisms of Pisha sandstone, and the property of modified Pisha sandstone material was studied by means of experiment and theoretical analysis. The rules of ion exchange expantion inhibition and gelatination solidification enhance were analysed by ion exchange and alkaline corrosion experiments, and the purpose of this work was produced a kind of practical, economical and environmental friendly engineering material using Pisha sandstone, and explore the resource utilization of Pisha sandstone. The physical and mechanical models of collapse and modification were established based on theoretical analysed. The modification mechanism of Pisha sandstone was revealed on the micro level, and XRD, FTIR, TG-DTG, MIP, SEM-EDS were used to analyze the composition, crystalline phases, microstructure and pore structure of modified Pisha sandstone. Compressive strength. Compressive strength, water resistence, water permeability and resistance to chemical corrosion were tested to evaluate the mechanical performance of modified Pisha sandstone. This work focused on the modified mechanism of Pisha sandstone, the development technology of modified Pisha sandstone and the properties of modified Pisha sandstone material. The achievement of this work was expected to offer suggestions for the development of modified Pisha sandstone engineering material and the resource utilization of Pisha sandstone, and even offer suggestions for treatment of water and soil loss and ecological restoration in Pisha sandstone area.

砒砂岩是一种特殊泥岩、泥沙岩，干燥呈石，遇水成沙，是黄河粗泥沙的主要来源。拟通过试验研究和理论分析，对砒砂岩抑胀固化改性机理及改性材料性能等问题进行深入系统研究。通过离子交换和溶蚀改性试验，分析砒砂岩离子交换抑胀及溶蚀胶凝固化规律，将砒砂岩研制成环保、经济、实用的工程材料，探索砒砂岩的资源化利用。通过理论分析，建立砒砂岩溃散及改性物理及力学模型。基于XRD、FTIR、TG-DTG、MIP和SEM-EDS分析，对砒砂岩改性材料的矿物组成、水化产物、微观结构和孔隙结构等进行研究，从微观角度揭示砒砂岩改性机理。通过抗压强度、耐水性能、水渗透性、抗化学侵蚀等测试，研究改性砒砂岩材料的工程性能。课题聚焦对砒砂岩改性机理及改性材料性能的研究。研究成果可为砒砂岩改性筑坝材料的研制和砒砂岩的资源化利用，乃至黄河中游砒砂岩区水土流失治理及生态修复等等提供科研借鉴。

项目采用试验研究和理论分析的手段，对砒砂岩抑胀固化改性机理及改性材料性能等问题进行深入系统研究。通过理论分析，找出了砒砂岩中胶结物、膨胀物及填充物三者之间的相互关系，获取了砒砂岩溃散、体积自由膨胀率、耐崩解性等参数，揭示了砒砂岩在水蚀-冻融-风蚀作用下的侵蚀溃散机制，探明了砒砂岩中膨胀性矿物的来源及化学成分等，建立了砒砂岩溃散及改性力学模型，提出了砒砂岩膨胀抑制、胶结增强、体积稳定性提升改性技术方案。通过离子交换和溶蚀改性试验，系统分析了砒砂岩离子交换抑胀及溶蚀胶凝固化规律，探明了阳离子种类、化合价、水合离子半径和水合离子表面电荷密度等对黏土矿物水化膨胀的影响，阐释了层间离子交换水化抑制机理，构建了砒砂岩水化抑制的阳离子交换序列。探明了砒砂岩各矿物成分在不同改性剂作用下的溶蚀规律，阐明了改性材料中胶凝产物的形成机理、形成过程及胶凝产物的种类和化学组成，探明了胶凝产物增强机理。研发了砒砂岩抑胀固化改性技术，并研制出了环保、经济、实用的改性砒砂岩工程材料，探索了砒砂岩的资源化利用。基于XRD、FTIR、TG-DTG、MIP和SEM-EDS分析，对砒砂岩改性材料的矿物组成、水化产物、微观结构和孔隙结构等进行了系统研究，从微观角度揭示了砒砂岩改性机理。通过抗压强度、耐水性能、水渗透性等测试，获取了改性砒砂岩材料的关键工程性能指标。项目的研究成果可为砒砂岩改性筑坝材料的研制和砒砂岩的资源化利用，乃至黄河中游砒砂岩区水土流失治理及生态修复等提供科研借鉴。