生石灰激发GGBS固化高含水率香港海相沉积物的物理力学性质研究  

Physical and mechanical performance of quicklime-activated GGBS stabilized Hong Kong marine sediment at high water content

作　　者：蔡光华 周伊帆[2] 潘智生 李江山[3] CAI Guang-hua;ZHOU Yi-fan;POON Chi Sun;LI Jiang-shan(College of Civil and Engineering,Nanjing Forestry University,Nanjing,Jiangsu 210037,China;Department of Civil and Environmental Engineering,The Hong Kong Polytechnic University,Kowloon,Hong Kong,China;State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan,Hubei 430071,China)

机构地区：[1]南京林业大学土木工程学院,江苏南京210037 [2]香港理工大学土木与环境工程系,香港九龙 [3]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,湖北武汉430071

出　　处：《岩土力学》2022年第2期327-336,共10页Rock and Soil Mechanics

基　　金：国家自然科学基金委员会与香港研究资助局联合科研资助基金(No.N_PolyU511/18);国家自然科学基金(No.41902286,No.51861165104);岩土力学与工程国家重点实验室开放基金课题(No.Z09026)。

摘　　要：海相沉积物处置已成为一项全球范围的挑战。在传统固化/稳定化方法中,环境污染严重的波兰特水泥(PC)是一种被广泛使用的固化剂。在此背景下,一种环境友好型的固化剂(生石灰与粒化高炉矿渣(简称GGBS)的混合料)取代PC来用在土壤改良领域。使用生石灰激发GGBS固化处理高含水率海相沉积物,并与PC固化海相沉积物进行比较。通过物理、化学试验及无侧限抗压强度试验分析了生石灰-GGBS固化海相沉积物的物理、化学和强度特性。结果表明:与PC固化海相沉积物相比,生石灰-GGBS固化沉积物具有体积收缩大、含水率低和密度略高的物理特性。随着生石灰比例的降低和养护时间的延长,生石灰-GGBS固化沉积物的pH值逐渐降低。生石灰-GGBS固化沉积物的无侧限抗压强度呈先增大(生石灰:固化剂为0.05~0.15)后减小(生石灰:固化剂为0.15~0.3)再增大(生石灰:固化剂为0.3~0.4)的趋势;当生石灰与固化剂的比值为0.15及0.4时,强度达到最大值;当生石灰与固化剂的比值为0.15时,生石灰-GGBS固化沉积物达到的峰值强度是相同条件下PC固化沉积物强度的1.4倍。该研究结果证实了GGBS与少量生石灰组合可以替代PC来固化高含水率的天然沉积物。The treatment of marine sediment has been a global-scale challenge. Portland cement(PC) is widely-used binder in the conventional stabilization/solidification method. Use of PC can cause serious environmental pollution. In this context, the environment-friendly binder(blend of quicklime and ground granulated blast-furnace slag(GGBS)) has been adopted to replace PC in the soil remediation field. This study investigated the quicklime-activated GGBS for the stabilization of marine sediment at high water content. The physicochemical and unconfined compression measurements were performed to analyze the physical, chemical,and strength characteristics of the quicklime-GGBS stabilized sediments. The results were compared with that of PC-stabilized sediment. As compared to the PC-stabilized sediment, the quicklime-GGBS stabilized sediment would generate larger volume shrinkage, lower water content, and slightly higher density. With reducing quicklime proportion and continuing curing time, the pH of the quicklime-GGBS stabilized sediment gradually decreases. The unconfined compressive strength of the lime-GGBS stabilized sediment shows a trend of first increasing(quicklime-binder ratio of 0.05–0.15) and then decreasing(0.15–0.3) and finally increasing again(0.3–0.4). The maximum strengths appear at the quicklime-binder ratios of 0.15 and 0.4. The maximum strength at the quicklime-binder ratio of 0.15 is 1.4 times than the corresponding PC-stabilized sediment under the same condition. The findings indicate that the combination of GGBS with little quicklime has the potential to replace PC for stabilizing natural sediment at high water content.

关 键 词：海洋沉积物 生石灰 粒化高炉矿渣(GGBS) 生石灰-固化剂比 力学性能 

分 类 号：TU43[建筑科学—岩土工程]