长江科学院院报 ›› 2017, Vol. 34 ›› Issue (5): 109-114.DOI: 10.11988/ckyyb.20160153

• 岩土工程 • 上一篇    下一篇

固化剂固化疏浚土的渗透性与微观机理研究

崔勇涛1, 2, 刘文白2   

  1. 1.中交疏浚技术装备国家工程研究中心有限公司,上海 201208;
    2.上海海事大学 海洋科学与工程学院,上海 201306
  • 收稿日期:2016-02-26 修回日期:2016-03-23 出版日期:2017-05-01 发布日期:2017-05-17
  • 通讯作者: 刘文白(1955-),男,山东济宁人,教授,博士,研究方向为岩土工程与港口结构工程,(电话)13371987356(电子信箱)liuwb8848@163.com。
  • 作者简介:崔勇涛(1989-),男,山东菏泽人,助理工程师,硕士,研究方向为港口海岸与近海工程结构与岩土工程,(电话)18801769763(电子信箱)18801769763@163.com。
  • 基金资助:
    国家自然科学基金项目(51078228); 国家海洋公益性行业科研专项(201105024-5); 2013年上海市研究生教育创新计划实施项目(20131129); 上海海事大学研究生学术新人培育计划(YXR2015095)

Permeability and Micro-mechanism of Dredged Mud Solidified with Curing Agent

CUI Yong-tao1, 2, LIU Wen-bai2   

  1. 1.CCCC National Engineering Research Center of Dredging Technology and Equipment Co., LTD,Shanghai 201208, China;
    2. College of Ocean Science and Engineering, Shanghai Maritime University, Shanghai 201306, China
  • Received:2016-02-26 Revised:2016-03-23 Online:2017-05-01 Published:2017-05-17

摘要: 用水泥和石灰等胶结剂及激发剂构成的固化剂对上海市横沙岛东滩的疏浚土进行改良,在不同养护龄期和固化剂掺量的条件下,用自配固化剂对岛区疏浚土进行了渗透试验。分析了固化疏浚土的渗透系数与固化剂掺量、养护龄期之间的关系, 得到了疏浚土渗透系数在不同固化剂掺入比和龄期下的变化规律。结果表明:固化疏浚土的渗透系数随固化剂掺量和龄期的增加而明显变小,但在同一龄期下,当固化剂掺量继续增加时,其渗透系数变化不大。并利用电镜扫描(SEM)对不同固化剂掺量和不同龄期下的固化疏浚土的微观结构进行观测,获得了疏浚土固化前后的微观结构SEM图,结合SEM图对疏浚土固化前后的微观结构变化做了定性的对比和分析,从固化疏浚土微观结构中发现固化疏浚土中含有水化硅酸钙(C-S-H)、氢氧化钙晶体、无定形文石、钙矾石等能够填充孔隙的胶结物,并从微观上解释了固化剂固化疏浚土的固化机理。

关键词: 固化疏浚土, 固化剂, 渗透系数, 微观结构, 固化机理

Abstract: Dredged mud from Hengsha island in Shanghai was improved by curing agent combining exciting agent and bonding agent such as cement and lime. Permeability tests were designed to study the permeability of the improved dredged mud in the presence of different curing ages and curing agent dosages. The relations of permeability coefficient of solidified dredged mud vs. curing agent content and curing time were analyzed, and the law of changes in permeability coefficient was obtained. Furthermore, the microstructure of solidified dredged mud with different curing agent contents and curing ages was observed by Scanning Electron Microscope (SEM) and the SEM images before and after solidification were obtained. According to the SEM images, changes in the microstructure of dredged mud before and after solidification were compared and analyzed. Results show that the permeability coefficient of solidified dredged mud decreased obviously with the increase of curing agent content and curing age; while under the same curing age, permeability coefficient changed little when curing agent content kept increasing. Micro-structure analysis indicates that calcium silicate hydrated (C-S-H), Ca(OH)2 crystal, CaCO3 crystal, amorphous aragonite and ettringite which could fill the pores were found in solidified dredged mud. Moreover, the mechanism of solidification of dredged mud was also analyzed from microscopic viewpoint.

Key words: solidified dredged mud, curing agent, permeability coefficient, microstructure, solidification mechanism

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