多元纳米材料对滨海水泥土抗腐蚀性能的影响

Effect of Multi-nanomaterials on the Corrosion Resistance of Coastal Cement Soil

水泥土地基存在强度提高有限、后期变形较大,海水腐蚀作用下易发生力学性能劣化等诸多工程问题。把Nano-SiO_(2)(NS)、Nano-CaCO_(3)(NCa)和Nano-Clay(NC)等三种纳米材料的单一、二元和三元组合掺入普通水泥土中,然后对经过海水长期腐蚀的试样进行无侧限抗压强度试验,探究纳米材料的种类、材料掺入组合、掺量对长期处于海水腐蚀环境中水泥土加固体抗压强度的影响。试验结果表明:单一添加时,Nano-SiO_(2)对处于海水腐蚀环境中水泥土无侧限抗压强度的增强效果最明显,Nano-CaCO_(3)次之,Nano-Clay最差。多元添加时,除NS+NCa这个二元组合外,其他二元、三元纳米组合由于材料间的相互作用,海水腐蚀环境中水泥土的抗压强度均低于纳米材料单一添加的情况。二元纳米组合NS+NCa对长期海水腐蚀环境水泥土抗压强度的发展优于单一添加,当NS+NCa的掺量为20‰时,能够在单一添加的基础上再提高15%的抗压强度,可以大幅提高长期海水腐蚀环境中水泥土的抗压强度。

Foundations of cement soil have many engineering problems such as limited strength improvement,large late deformation,and susceptibility to mechanical property deterioration under the corrosive effect of seawater.In this paper,single,binary and ternary combinations of three nanomaterials,such as Nano-SiO_(2)(NS),Nano-CaCO_(3)(NCa)and Nano-Clay(NC),were incorporated into ordinary cement soil,and then the specimens corroded by seawater for a long time were tested for unilateral compressive strength to investigate the effects of the type of nanomaterials,material incorporation combination and incorporation amount on the compressive strength of cement soil in long term corrosive environment of seawater.The effect of the type,combination and amount of nanomaterials on the compressive strength of the soil in the long term seawater corrosion environment was investigated.The test results showed that the effect of Nano-SiO_(2) on the unconfined compressive strength of cement soil in seawater corrosive environment was the most obvious and most effective with single addition,followed by Nano-CaCO_(3) and the worst with Nano-Clay.When multiply added,except for NS+NCa,a binary combination,all other binary and ternary nano-combinations have lower compressive strength of cement soil in seawater corrosive environment than the case of single addition of nanomaterials due to the interaction between materials.The development of compressive strength of binary nano-combination NS+NCa on long-term seawater corrosive environment cement soil is better than single addition,when the doping amount of upper NS+NCa is 20‰,it can improve the compressive strength of cement soil in long-term seawater corrosive environment by 15%on top of single addition,which can significantly improve the compressive strength of cement soil in long term seawater corrosive environment.