摘要
蛇纹石屏蔽混凝土是一种长期应用于高温条件下仍能保持高结晶水含量的中子屏蔽材料,但其密实度低,缺乏有效吸收热中子的硼元素。作为硼元素的来源,硼酸是生产屏蔽混凝土的有效材料,但在以水泥为主的水化体系中,硼酸的掺入会抑制水泥水化过程,导致材料强度及耐久性劣化。本研究通过改性高浓度硼酸溶液,诱导水泥浆体中游离硼酸盐生成高硼含量与结晶水含量的戈硼钙石,增加体系中硼元素含量的同时解除硼酸对水泥水化的抑制作用,研究改性高浓度硼酸溶液对蛇纹石屏蔽混凝土工作性能、力学性能、高温残余抗压强度、微观结构与屏蔽性能的影响。结果表明:掺加改性高浓度硼酸溶液对蛇纹石屏蔽混凝土的凝结时间、常温力学性能、高温残余抗压强度均无不良影响。掺加改性高浓度硼酸溶液后,蛇纹石屏蔽混凝土在400℃高温残余抗压强度提高了43.5%,常温下半值层降低了31.7%,350℃保温至恒重后半值层降低了21.4%,对中子射线的屏蔽能力增强。
Serpentine shielded concrete is a neutron shielding material that can maintain high crystal water content even under high temperature condition for a long time,but its compactness is low and it lacks boron element that can effectively absorb thermal neutrons.As a source of boron,boric acid is an effective material for producing shielded concrete.However,in cement-based hydration systems,the addition of boric acid can inhibit the cement hydration process,leading to deterioration of material strength and durability.This study induced the formation of high boron content and crystalline water content of boric acid in cement slurry by modifying high concentration boric acid solution.The boron content in the system was increased while the inhibitory effect of boric acid on cement hydration was relieved.The effect of modified high concentration boric acid solution on workability,mechanical properties,high-temperature residual compressive strength,microstructure and shielding performance of serpentinite shielded concrete was studied.The results show that the addition of modified high concentration boric acid solution has no adverse effects on the setting time,mechanical properties at room temperature,and high-temperature residual compressive strength of serpentine shielded concrete.After adding modified high concentration boric acid solution,the high-temperature residual compressive strength at 400℃of serpentinite shielding concrete increases by 43.5%,the half value layer at room temperature decreases by 31.7%,and the half value layer decreases by 21.4%after insulation at 350℃to constant weight,enhancing the shielding ability of neutron rays.
作者
甘学彧
陈帅
耿海宁
李宗刚
马浩森
陈伟
侯硕
李秋
GAN Xueyu;CHEN Shuai;GENG Haining;LI Zonggang;MA Haosen;CHEN Wei;HOU Suo;LI Qiu(State Key Laboratory of Silicate Materials for Architectures,Wuhan University of Technology,Wuhan 430070,China;School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China;China Nuclear Power Technology Research Institute Co.,Ltd.,Shenzhen 518000,China;Hubei Urban Construction Vocational and Technological College,Wuhan 430205,China)
出处
《硅酸盐通报》
CAS
北大核心
2024年第6期2047-2055,共9页
Bulletin of the Chinese Ceramic Society
基金
国家自然科学基金面上项目(52072279)。
关键词
蛇纹石屏蔽混凝土
中子屏蔽性能
高温残余抗压强度
改性高浓度硼酸溶液
戈硼钙石
凝结时间
serpentine shielded concrete
neutron shielding property
high-temperature residue compressive strength
modified high concentration boric acid solution
gowerite
setting time
