摘要
在海涂淤泥中掺入不同量NaOH改变淤泥孔隙溶液的pH值,再掺入等量水泥做固化试验。通过室内试验测试淤泥固化土的基本力学性质,探讨NaOH对仅用水泥固化淤泥的改善作用,研究无侧限抗压强度与NaOH掺量的关系和各个龄期淤泥固化土的应力-应变关系,并分析固化淤泥的微观结构特征。研究表明,NaOH掺量不大于0.8%时,孔隙溶液pH值的改变对Ca(OH)2浓度影响很小,对固化强度的改善效果不明显;NaOH掺量大于1.6%时,随着掺量的增大,可以较大地提高淤泥固化强度,破坏应变较小,具有脆性破坏性质;NaOH掺量为3.2%时,90 d强度约为不掺NaOH固化淤泥的2倍;微观结构反映出各种状态水化产物形成网状骨架并且填充孔隙,使得固化土具有一定的强度。
The pH value of pore solution in tideland slugde was changed by adding different amounts of NaOH,then curing test was carried out by mixing with equal amount of cement. The basic mechanical data of stabilized sludge was determined by laboratory test. Discuss the improvement effect of NaOH on the pure cement-stabilized sludge, research on the relationship between unconfined compressive strength and the NaOH content and the stress-strain relations in all ages,and analysis the microstructure characteristics of the stabilized sludge. The research showed:when NaOH content was less than 0.8%,the change of pore solution pH value had little effect on Ca(OH)2 concentration,and the improvement effect on the curing strength was not obvious;whereas,when NaOH content was greater than 1.6%,the curing strength could be greatly improved with increasing dosage,failure stress was small and has the nature of brittle fracture:when NaOH content was 3.2%,90 d strength was about 2 times of the stabilized sludge without NaOH. Microstrueture showed that various states of hydration products formed mesh skeleton and filled pores, making stabilized sludge have certain strength.
出处
《新型建筑材料》
北大核心
2011年第5期9-12,16,共5页
New Building Materials
基金
浙江省重大科技专项重点工业项目(2009C01032-1)
关键词
淤泥固化土
无侧限抗压强度
应力-应变
微观结构
stabilized tideland sludge
unconfined compressive strength
stress-strain
mierostructure