OPC-MCA固化剂对盾构废泥的固化性能及其微观作用机制研究  

Study on the curing performance and microscopic action mechanism of OPC-MCA curing agent on shield waste muck

作　　者：张恒根 王卫华[2] 邓声贵[3] 何昊[1] 刘涛[1,4] ZHANG Henggen;WANG Weihua;DENG Shenggui;HE Hao;LIU Tao(Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering,Ocean University of China,Qingdao 266100,China;School of Resources and Safety Engineering,Central South University,Changsha 410083,China;School of Marine Earth Sciences,Ocean University of China,Qingdao 266100,China;Laboratory for Marine Geology,Qingdao Marine Science and Technology Center,Qingdao 266237,China)

机构地区：[1]山东省海洋环境与地质工程重点实验室,中国海洋大学,山东青岛266100 [2]中南大学资源与安全工程学院,湖南长沙410083 [3]中国海洋大学海洋地球科学学院,山东青岛266100 [4]青岛海洋科技中心海洋地质过程与环境功能实验室,山东青岛266237

出　　处：《中南大学学报（自然科学版）》2024年第4期1492-1508,共17页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(42277139,U2006213);中央高校基本科研业务费专项资金资助项目(202261062)。

摘　　要：通过添加高炉矿渣(GGBS)、脱硫石膏(FGDG)、铝酸钙粉、生石灰和明矾到普通硅酸盐水泥P.O42.5(OPC)中,制备一种新型盾构废泥改良材料OPC-MCA。首先,通过正交测试法确定OPC-MCA中各原料的最优配比。然后,使用该材料和OPC在10%~40%的掺量下处理芜湖市城南过江隧道工程产生的盾构废泥,并检测不同固化时间(3、7、28 d)下的抗压强度。最后,采用扫描电镜(SEM)、工业CT系统和X射线衍射(XRD)观察和分析固化后废泥试样的微观形貌、孔隙和裂纹特征以及矿物成分变化。研究结果表明:OPCMCA的最优材料配比为51%OPC、32%GGBS、8%FGDG、5%铝酸钙粉、3%生石灰、1%明矾;OPCMCA对芜湖盾构废泥的固化能力比OPC的强,在低掺量情况下更是如此;固化剂掺量和固化时间的增加会导致试样强度增加、脆性增强,并使部分试样转变为拉伸破坏;在OPC-MCA固化的试样中检测到了OPC固化试样中未检测到的水化硅铝酸钙(C-A-S-H)和单硫型硫铝酸盐(AFm),并且钙矾石(AFt)含量也更高;在同等掺量下,OPC-MCA固化试样中大尺寸孔隙的比例以及孔隙的总体积均比OPC固化试样的小。A new shield waste muck modification material,OPC-MCA,was prepared by adding ground granulated blast-furnace slag(GGBS),fuel gas desulfurization gypsum(FGDG),calcium aluminate powder,quicklime,and alum to ordinary Portland cement P.O42.5(OPC).Firstly,the optimal ratio of each raw material in OPC-MCA was determined through orthogonal experiments.Then,the shield waste muck generated from the Chengnan Crossriver Tunnel Project in Wuhu City was treated with OPC-MCA and OPC at various dosages ranging from 10%to 40%,and the compressive strength at different curing times(3,7 and 28 d)was tested.Furthermore,the microstructure,pore and crack characteristics,and mineral composition of the solidified waste muck specimens were observed and analyzed using scanning electron microscope(SEM),industrial CT system,and X-ray diffraction(XRD).The results show that the optimal material ratio of OPC-MCA is 51%OPC,32%GGBS,8%FGDG,5%calcium aluminate powder,3%quicklime,and 1%alum.OPC-MCA exhibits stronger curing ability on the Wuhu shield waste muck compared to OPC,especially at low dosages.The increase in dosage and curing time results in higher strength and brittleness of the specimens,and some specimens exhibit tensile failure.Calcium aluminium silicate hydrate(C-A-S-H)and monosulfate(AFm),which are not detected in the OPC cured specimens,are detected in the OPC-MCA cured specimens,and the ettringite(AFt)content is also higher.Under the same dosage,the proportion of larger-sized pores as well as the total volume of pores in OPC-MCA cured specimens are smaller than those in OPC cured specimens.

关 键 词：盾构废泥 固化剂 CT扫描 力学性能 反应机理 

分 类 号：TU449[建筑科学—岩土工程] TQ172[建筑科学—土工工程]