海水拌合对盐渍土加固性能的影响  

Effect of Seawater Mixing on Reinforcement Performance of Saline Soil

作　　者：白旭昕 陈明涛 何小军 赵庆新[1] BAI Xuxin;CHEN Mingtao;HE Xiaojun;ZHAO Qingxin(Key Laboratory of Green Construction and Intelligent Operation of Civil Engineering of Hebei Province,Yanshan University,Qinhuangdao 066004,China;Sinohydro Engineering Bureau 4 Co.,Ltd,Xining 810007,China;Shijiazhuang Institution of Railway Technology,Shijiazhuang 050000,China)

机构地区：[1]燕山大学,河北省土木工程绿色建造与智能运维重点实验室,秦皇岛066004 [2]中国水利水电第四工程局有限公司,西宁810007 [3]石家庄铁路职业技术学院,石家庄050000

出　　处：《硅酸盐通报》2020年第8期2683-2690,共8页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金(51578477)。

摘　　要：用水泥和磨细矿渣制作复合土壤固化剂,其中水泥与磨细矿渣的掺量比分别为1∶1和1∶3。在固化剂掺量为总质量(干土、水和固化剂质量之和)的10%和20%的条件下,分别用自来水和黄骅港涂滩区天然海水加固滨海盐渍土(以下简称加固土)。测试各配比加固土28 d和90 d龄期的无侧限抗压强度,并结合加固土烧失量、固结物含量、X射线衍射(XRD)、扫描电子显微镜(SEM)和能谱(EDS)的结果分析了海水拌合对盐渍土加固性能的影响及机理。结果表明:当固化剂含量为20%,水泥与矿渣比例为1∶1时,海水拌合的加固土无侧限抗压强度的平均值高出自来水拌合的加固土约42%;水泥与矿渣比例为1∶3时,自来水拌合的加固土无侧限抗压强度的平均值高出海水拌合的加固土约23%。总体上加固土强度与固结物含量呈正相关,当固化剂含量相同时,加固土强度取决于孔隙中水化产物的数量;当固结物含量基本相同时,加固土的强度是水化产物数量与加固土的密实度共同作用的结果。海水拌合会抑制矿渣颗粒的水化反应,因此,当固化剂中矿渣比例较高时,海水拌合的加固土强度会低于自来水拌合的加固土。Cement and ground slag were used to make composite soil solidifying agent.The mixing ratio of cement and ground slag was 1∶1 and 1∶3,respectively.Under the condition that the amount of soil curing agent was 10%and 20%of the total mass(the sum of dry soil,water and curing agent mass),tap water and natural seawater in the Huanghua Port mudflat area were used to reinforce the coastal saline soil,respectively.The unconfined compressive strength of different reinforced soils(saline soils strengthened by curing agents)at 28 d and 90 d were tested.The effect and mechanism of seawater mixing on the consolidation performance of saline soil were analyzed by the results of loss on ignition,the consolidation content,X-ray diffraction(XRD),scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS).The results show that when the content of the curing agent is 20%and the ratio of cement to slag is 1∶1,the average value of the unconfined compressive strength of the reinforced soil mixed with seawater is about 42%higher than that of the reinforced soil mixed with tap water.When the ratio of cement to slag is 1∶3,the average value of the unconfined compressive strength of the reinforced soil mixed with tap water is about 23%higher than that of the reinforced soil mixed with seawater.On the whole,the strength of reinforced soil is positively related to the consolidation content.When the content of solidified agent is the same,the strength of reinforced soil depends on the number of hydration products in the pores.When the consolidation content is basically the same,the strength of reinforced soil is the result of the both action of the number of hydration products and the compactness of reinforced soil.Seawater mixing can inhibit the hydration reaction of slag particles.Therefore,when the proportion of slag in the curing agent is high,the strength of seawater mixing reinforced soil is lower than that of tap water mixing reinforced soil.

关 键 词：盐渍土 海水拌合 加固性能 无侧限抗压强度 磨细矿渣 水化反应 土壤固化剂 

分 类 号：TU528[建筑科学—建筑技术科学]