Experimental Study On The Engineering Characteristics Of Solidified Beach Clay

The beach clay is an important reserve land resource of Zhejiang Province, of which the beach reclamation can effectively alleviate the land bottleneck in the coastal areas of Zhejiang Province. However, the beach clay has the properties of high water content, low intensity and large deformation, which must be handled before development and utilization. Curing is one of the effective feasible foundation treatment methods for beach clay. Due to the complexity of composition and diversity of the causes of beach clay, different curing agents and additives have different curing effect for beach clay. Therefore, it has important theoretical and practical significance to study the mechanical properties of solidified beach clay, to compound curing agent suitable for specific area, to analyze the strength and deformation characteristics of solidified beach clay considering different factors, to investigate the effects of additives on the curing effectiveness and curing mechanism, and to guide the engineering practice.Based on the previous research work, this dissertation makes a series of investigations on solidification and engineering characteristics of beach clay by means of unconfined compressive strength test, direct shear test and scanning electron microscope test. The main work and results are as follows:(1) Through the single doped experiment, the effect of amount of cement, water reducing agent, lime, gypsum, fly ash, triethanolamine, sodium sulfate, sodium chloride on the unconfined compressive strength and change law of solidified beach clay is analyzed, and the effect of amount of admixture and curing age on the strength and deformation of solidified soil is further investigated.(2) By means of orthogonal test, the main influence and secondary factors of additives on the solidification effect of beach clay is analyzed and the optimum ratio of curing agent is determined.(3) Through the contrast test of cement stabilized beach clay and cement+composite curing agent solidified beach clay, the effect of cement content, curing agent content and curing period, etc., on the shear strength, cohesion and angle of internal friction of stabilized soil is studied by means of direct shear test, and the effect of cement content, composite curing agent content and curing period, etc., on the relationship of shear stress and shear displacement of stabilized soil is analyzed.(4) Through scanning electron microscope test, the microstructure of beach clay, cement solidified beach clay and cement+composite curing agent solidified beach clay is analyzed, and the effect of cement content, curing agent content and curing period, etc., on the internal pore structure and strengthening mechanism of solidified soil is investigated.