Pore Structure Evolution and Strength Development of Set Cement
ZHENG Shaojun1,2, LIU Tianle1,2, GAO Peng3, JIANG Guosheng1,2, FENG Yingtao4, LI Lixia1,2, CHEN Yu4
1 Faculty of Engineering, China University of Geosciences, Wuhan 430074, China 2 Unconventional Cementing and Special Strengthening Laboratory, China University of Geosciences, Wuhan 430074, China 3 School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China 4 Oilfield Chemistry R&D Institute, COSL, Sanhe 065201, China
Abstract: Pore structure development law of set cement can provide a crucial reference for cementing process design and cementing quality evaluation. Herein, based on the cement hydration numerical simulation model HYMOSTRUC3D, a novel set cement hydration model was established, the CH content and compressive strength of set cement were obtained to compare the tested results of XRD and the mechanical testing machine respectively, where the deviations between the simulation results and the experimental results were 0.7%—8.7% and 0.5%—10.7%, respectively. The results were in good agreement, which verified the accuracy of the model. Then, based on the established model, the mineral components (C3S, C2S, C3A and C4AF), hydration products (C-S-H and CH), porosity and pore size distribution, etc. with water-cement ratio as well as hydration age, besides a three-dimensional microstructure of set cement was reconstructed in Para View. In addition, Ryshkewitch function, Schiller function and quadratic linear function were chosen to fit the relationship between compressive strength and the total porosity or the capillary porosity, respectively. The results show that:(1)the porosity gradually decreases, the pore size distribution gradually narrows and the compressive strength gradually increases during the cement hydration process. With the increase of water to cement ratio, the porosity increases, the wide range of pore size distribution increases, and the compressive strength decreases. (2)The compressive strength of set cement is negatively correlated with total porosity or capillary porosity, Ryshkewitch function, Schiller function and quadratic linear function are used to fit the relationship between compressive strength and total porosity or to fit the relationship between compressive strength and capillary porosity, while the fitting determination coefficients are 0.92, 0.85, 0.91 and 0.97, 0.95, 0.97 respectively. (3)Compared with Schiller function and quadratic linear function, Ryshkewitch function is more universal to study the relationship between compressive strength and total porosity or capillary poro-sity. Capillary porosity is the main factor that determines the compressive strength of set cement. (4)y=191.5e-0.074x can be used to predict and study the relationship between compressive strength and capillary porosity.
1 Brandro N B, Roehl D, De A S, et al. Journal of Petroleum Science & Engineering, 2017, 157, 422. 2 Liu C J, Huang B Z, Xu T T, et al.Cement injection theory and application in oil and gas wells. Petroleum Industry Press, China,2001(in Chinese). 刘崇建, 黄柏宗, 徐同台, 等. 油气井注水泥理论与应用,石油工业出版社, 2001. 3 Ghabezloo S, Sulem J, Guedon S, et al.Cement and Concrete Research, 2008, 38(12), 1424. 4 Tang J, Zhang C G, Zhang B X, et al.Petroleum Exploration and Deve-lopment, 2015, 43(3), 470(in Chinese). 唐军, 章成广, 张碧星, 等. 石油勘探与开发, 2015, 43(3), 470. 5 Wang R H, Wang C W, B Y H, et al.Journal of China University of Petroleum (Edition of Natural Science), 2008, 32(1), 78(in Chinese). 王瑞和, 王成文, 步玉环, 等. 中国石油大学学报(自然科学版), 2008, 32(1), 78. 6 Zhou S M, Li G S, Wang Q C.Petroleum Exploration and Development, 2013, 40(1), 108(in Chinese). 周仕明, 李根生, 王其春. 石油勘探与开发, 2013, 40(1),108. 7 Fan K, Zhu W Q, Zhou D Y, et al.Acta Petrolei Sinica, 2015, 36(4),86(in Chinese). 范坤, 朱文卿, 周代余, 等. 石油学报, 2015, 36(4),86. 8 Dousti M R, Boluk Y, Bindiganavile V.Construction and Building Mate-rials, 2019, 205(30),457. 9 Lu S C, Wang X Y, Meng Z R, et al.RSC Advances, 2019, 9,26692. 10 Liu K Q, Cheng X W, Zhang X G, et al.Transport in Porous Media, 2018,124(2),471. 11 Wei T C, Cheng X W, Wang S Z, et al.Materials Reports, 2016(Z2),415(in Chinese). 韦庭丛, 程小伟, 王升正, 等. 材料导报,2016(Z2), 415. 12 Li L B, Zhang H M, Guo X Y, et al.Construction and Building Mate-rials, 2019, 227, 2. 13 Van Breugel K. Simulation of hydration and formation of structure in har-dening cement-based materials. Ph.D. Thesis, Delft University of Techno-logy, The Netherlands, 1991. 14 Van Breugel K. Cement & Concrete Research, 1992, 25(2), 319. 15 Konders E A B. Simulation of volume changes in hardening cement-based materials. Ph.D. Thesis, Delft University of Technology, The Netherlands, 1997. 16 Ye G. Experimental study and numerical simulation of the development of the microstructure and permeability of cementitious materials. Ph.D. Thesis, Delft University of Technology, The Netherlands, 2003. 17 Gao P. Simulation of hydration and microstructure development of blended cements. Ph.D. Thesis, Delft University of Technology, The Netherlands, 2018. 18 Pandey S P, Sharma R L.Cement & Concrete Research, 2000, 30(1),19. 19 Kearsley E P, Wainwright P J.Cement and Concrete Research, 2002, 32(2),233. 20 Zhang M Z. Multiscale lattice Boltzmann-finite element modelling of transport properties in cement-based materials. Ph.D. Thesis, Delft University of Technology, The Netherlands, 2013. 21 Qian Z W, Schlangen E, Ye G, et al.Materiales de Construction, 2010, 60(297), 8. 22 Wang X Y, Lee H S.Construction & Building Materials, 2012, 28(1), 12. 23 Nguyen V T. Rice husk ash as a mineral admixture for ultra-high-perfor-mance concrete. Ph.D. Thesis, Delft University of Technology, The Nethe-rlands, 2011. 24 Jin X Y, Wang Y W, Tian Y, et al.Journal of Building Materials, 2014, 17(5), 862(in Chinese). 金贤玉, 王宇纬, 田野, 等. 建筑材料学报, 2014, 17(5),862. 25 Zhang M Z, Ye G, Van Breugel K.Materiales de Construccion, 2010, 60(300), 19. 26 Bentz D P, Garboczi E J.Cement and Concrete Research, 1991, 21, 325. 27 Bentz D P.Journal of the American Ceramic Society, 1997, 80(1), 5. 28 Zhao P Q, Liang C, Sun C K, et al.Materials Reports, 2019, 33(Z2), 646(in Chinese). 赵丕琪, 梁辰, 孙传奎, 等.材料导报, 2019, 33(Z2), 646. 29 Yu X, Yu C, Ran Q P, et al.Materials Reports B:Research Papers, 2019, 33(7), 2340(in Chinese). 余鑫, 于诚, 冉千平, 等. 材料导报:研究篇, 2019(7),2340. 30 Maekawa K, Ishida T, Kishi T. Journal of Advanced Concrete Technology, 2003, 1(2),91. 31 Zheng S J, Liu T L, Jiang G S, et al. Materials Reports B:Research Papers, 2020, 34(11),56. 郑少军, 刘天乐, 蒋国盛, 等. 材料导报:研究篇, 2020, 34(11),56. 32 Wu D J, She W, Miao C W, et al.Journal of Building Materials, 2020, 23(1), 15(in Chinese). 吴大江, 佘伟, 缪昌文, 等. 建筑材料学报, 2020, 23(1), 15. 33 Chan N, Young R C, Li S. Water Science & Technology, 2018, 77(6),1744. 34 Li Y X, Chen Y M, Wei J X, et al.Cement & Concrete Research, 2006, 36(9),1741.