底泥基地质聚合物注浆材料制备试验研究

Experimental study on preparation of geological polymer grouting material based on dredged sediment

河湖环境治理工程中产生的底泥的高效处置问题已经成为环境治理的重要难题,在岩土工程领域常用的注浆加固方法需要大量的注浆材料。综合底泥处置难题和岩土工程注浆材料的需求,提出以纯底泥作为基础物质进行地质聚合物注浆材料的研究。以武汉南湖清淤工程产生底泥作为原料,在分析底泥基本性质基础上,结合前期碱激发探索,以碱激发和热活化相结合开展底泥基地质聚合物注浆材料的制备试验,并通过正交试验探究碱性激发剂模数、碱当量、水灰比等因素对底泥基地质聚合物强度的影响,所得纯底泥基地质聚合物28 d强度达到16.37 MPa,然后通过X射线衍射(XRD)和傅里叶红外光谱试验(FTIR)方法对地质聚合物凝胶的生成过程进行分析。研究结果表明,在碱激发和热活化共同作用下,纯底泥基地质聚合物注浆材料的制备是可行的,能够基本满足工程需求,通过后续研究有望解决大量底泥的处置难题,也可为工程建设提供一种新的注浆材料。

The efficient disposal of sediment in river and lake environmental control engineering has become an important problem of environmental control.The grouting reinforcement method commonly used in geotechnical engineering needs a large number of grouting materials.Considering the difficult problem of sediment disposal and the demand for grouting materials in geotechnical engineering,this paper proposes to study geopolymer grouting materials with pure sediment as the basic material.Taking Wuhan South Lake to produce sediment dredging engineering as raw material,based on analyzing the basic properties of the sediment,this paper combines alkali excitation and thermal activation method of sediment base polymer preparation experiment.On this basis,the orthogonal experiment is carried out to explore the alkaline exciting agent module,alkali equivalent,water cement ratio,and other factors that influence on the strength of sediment mass base polymer.The strength of the prepared base polymer reaches 16.37 MPa in 28 days.X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FTIR)reveal the formation process of geopolymer gel.The results show that under the combined action of alkali excitation and thermal activation,the preparation of sediment base polymer is feasible and can meet the engineering needs.This method can not only solve the problem of disposal of a large amount of sediment but also provide a low-carbon green cementitious material for engineering construction.