丙烯酰胺常温原位聚合改性盐渍土生态胶凝材料的试验研究

Experiment study of AM in-situ polymerization modification on saline soil ecological cementing materials

研究了丙烯酰胺(AM)常温原位聚合对盐渍土生态胶凝材料力学性能的影响及增强机理。通过正交试验考察了聚合条件对盐渍土生态胶凝材料力学性能的影响,确定了力学性能较佳的工艺条件。并采用超景深电镜、红外光谱对盐渍土生态胶凝材料的微观结构进行分析。结果表明:丙烯酰胺常温原位聚合改性后的盐渍土生态胶凝材料的28 d抗折、抗压强度分别可达5.59、15.0MPa,较改性前分别提高了291%和285%,软化系数为0.50;超景深电镜与红外光谱分析表明,AM在盐渍土中聚合得到的PAM与盐渍土之间形成氢键,产生强的吸附作用,加强颗粒之间胶结作用,抑制黏土颗粒的分散运移,从而使其强度和耐水性提高。

The influence and the enhancement mechanism of acrylamide（AM） in--situ polymerization on the mechanical properties of saline soil ecological cementing materials was studied in this paper. The influence of the polymerization conditions on mechani- cal properties was investigated by the orthogonal analysis,obtained the optimum conditions. And microstructure of saline soil eco- logical cementing materials was analyzed by super depth of field electron microscope and FTIR. The results showed that： the modi- fied saline soil ecological cementing material＇s 28 d flexural strength and compressive strength can reach 5.59 MPa and 15.0 MPa, increased 291% and 285% respectively by the AM in-situ polymerization at room temperature. The softening coefficient was 0.50. The super depth of field electron microscope and FTIR showed that hydrogen bonding was formed between polyamide chain and saline soil particles,produced strong adsorption for saline soil particles,strengthen cementation between saline soil particles,re- strained saline soil particles dispersed migration,which lead to increase of strength and water resistance.