Mechanical Property Attenuation Mechanism of Cement-Sodium Silicate Double Liquid Slurry under Water Corrosion

Abstract

Abstract: After long-term service in rich water environment, the mechanical properties of double liquid slurry are easily degraded by water corrosion. The variation law of the mechanical property attenuation of cement-sodium silicate double liquid slurry under the mixing ratio parameters and curing system was studied. Combined with various microscopic analysis methods, the mechanism of the mechanical property attenuation of cement-sodium silicate double liquid slurry under rich water environment was analyzed from the aspects of mineral composition and microstructure evolution. The results show that, curing in the low water content sand layer of 10%, 15% (mass fraction) are beneficial to the early strength development, but the strength gradually decreases in the later stage. The early strength of the test block in the 25% (mass fraction) high water content sand layer decreases by 23.5% compared to the 15% (mass fraction) water content sand layer, but the water corrosion effect is significantly weakened in the later stage, and the compressive strength at 220 d increases by 15% compared to 90 d. The standard curing conditions accelerate the deterioration of the mechanical properties of double liquid slurry, and the strength of the test block is 80.6% and 91.0% lower than that of water curing and sealed curing, respectively. The development of the mechanical properties is mainly controlled by hydration reaction and water corrosion. In the early stage, hydration reaction dominates, and in the later stage, water corrosion dominates. The development of the mechanical properties is essentially the effect of superposition of the two effects. The double liquid slurry material system is maintained in the rich water environment for a long time, and the hydration products on the outside of the matrix are constantly migrating and dissolving out. The outer layer of the test block forms a porous structure coating layer with a certain thickness, and becomes a migration channel for sodium ions, silicate ions and hydration products in the internal structure, which leads to continuous deterioration of the mechanical properties of the matrix.

Key words: shield tunneling, simultaneous grouting, cement-sodium silicate, double liquid slurry, water corrosion, hydration product

CLC Number:

TU528

CUI Jia, CHEN Junwei, XIA Zhongsheng, SHA Jianfang, LIU Jianzhong, HAN Fangyu, GUO Fei. Mechanical Property Attenuation Mechanism of Cement-Sodium Silicate Double Liquid Slurry under Water Corrosion[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2023, 42(10): 3470-3478.

References

[1] 吴昌胜. 大直径盾构隧道施工引起的地层变形研究[D]. 南京: 东南大学, 2018.
WU C S. Study on ground deformation caused by large diameter shield tunnel construction[D]. Nanjing: Southeast University, 2018 (in Chinese).
[2] 唐晶晶, 黄靖, 周永祥, 等. 盾构法同步注浆材料的研究进展[J]. 现代城市轨道交通, 2016(4): 89-92.
TANG J J, HUANG J, ZHOU Y X, et al. Study progress of synchronous grouting material for shield tunneling method[J]. Modern Urban Transit, 2016(4): 89-92 (in Chinese).
[3] 张凯. 水泥-水玻璃双液浆在地铁施工中的应用[J]. 现代城市轨道交通, 2011(增刊1): 74-76.
ZHANG K. Application of cement-sodium silicate double liquid slurry in subway construction[J]. Modern Urban Transit, 2011(supplement 1): 74-76 (in Chinese).
[4] 蔡乾广, 贺磊. 双液微扰动注浆在治理盾构错缝管片收敛中的应用[J]. 城市勘测, 2019(1): 193-195.
CAI Q G, HE L. Application of double-liquid micro-perturbation grouting in the convergence treatment of staggered shield segments[J]. Urban Geotechnical Investigation & Surveying, 2019(1): 193-195 (in Chinese).
[5] 张民庆, 韩忠存, 施宏峰. 超细水泥-水玻璃双液浆的研究及应用[J]. 铁道工程学报, 1998, 15(4): 136-145.
ZHANG M Q, HAN Z C, SHI H F. Research and application of superfine cement and sodium silicate mixed grout[J]. Journal of Railway Engineering Society, 1998, 15(4): 136-145 (in Chinese).
[6] 安妮, 赵宇, 石文广, 等. 水泥-水玻璃双液浆的特性试验研究及应用[J]. 铁道建筑, 2011, 51(12): 128-130.
AN N, ZHAO Y, SHI W G, et al. Experimental study and application of characteristics of cement-sodium silicate double liquid slurry[J]. Railway Engineering, 2011, 51(12): 128-130 (in Chinese).
[7] 徐晶, 范杰, 黄俊, 等. 盾构施工同步双液注浆材料的配合比及性能研究[J]. 混凝土, 2021(10): 151-154.
XU J, FAN J, HUANG J, et al. Research on the proportion and properties of a simultaneous two-component backfill grouting material in shield construction[J]. Concrete, 2021(10): 151-154 (in Chinese).
[8] 马金池. 管片双液注浆材料及配方研究[J]. 铁道勘察, 2019, 45(1): 72-76.
MA J C. Study on the grouting material and formula of double-liquid behind the segment[J]. Railway Investigation and Surveying, 2019, 45(1): 72-76 (in Chinese).
[9] 周朋, 谢松林, 李强. 水胶比对混凝土性能及气孔结构的影响分析[J]. 硅酸盐通报, 2018, 37(3): 974-978.
ZHOU P, XIE S L, LI Q. Effect of water-binder ratio on properties and pore structure of concrete[J]. Bulletin of the Chinese Ceramic Society, 2018, 37(3): 974-978 (in Chinese).
[10] 许茜, 王彦明, 邵磊, 等. 注浆材料的固化机理与抗水溶蚀性能研究[J]. 21世纪建筑材料, 2010, 2(2): 30-33.
XU Q, WANG Y M, SHAO L, et al. Study on curing mechanism and water corrosion resistance of grouting materials[J]. 21^st Century Building Materials, 2010, 2(2): 30-33 (in Chinese).
[11] 许茜. 注浆材料的抗水性能及渗透注浆扩散规律数值模拟研究[D]. 济南: 山东大学, 2010.
XU Q. Numerical simulation study on water resistance of grouting materials and diffusion law of infiltration grouting[D]. Jinan: Shandong University, 2010 (in Chinese).
[12] 田焜, 丁庆军, 陈跃庆, 等. 盾构隧道大掺量粉煤灰同步注浆材料优化设计[J]. 隧道建设, 2007, 27(4): 26-29.
TIAN K, DING Q J, CHEN Y Q, et al. Optimal design of high volume fly ash simultaneous grouting material for shield tunnel[J]. Tunnel Construction, 2007, 27(4): 26-29 (in Chinese).
[13] 刘四进. 侵蚀环境作用下盾构隧道结构性能衰退演变机理研究[D]. 成都: 西南交通大学, 2017.
LIU S J. Study on the mechanism of structural performance decline and evolution of shield tunnel under corrosive environment[D]. Chengdu: Southwest Jiaotong University, 2017 (in Chinese).
[14] WANG S M, HE C, NIE L, et al. Study on the long-term performance of cement-sodium silicate grout and its impact on segment lining structure in synchronous backfill grouting of shield tunnels[J]. Tunnelling and Underground Space Technology, 2019, 92: 103015.
[15] ZHU Z J, WANG M, LIU R T, et al. Study of the viscosity-temperature characteristics of cement-sodium silicate grout considering the time-varying behaviour of viscosity[J]. Construction and Building Materials, 2021, 306: 124818.