摘要
为了提升红层泥岩填料的微生物改良效果,将木质素磺酸钙、玄武岩纤维作为外加剂协同微生物改良红层泥岩填料,开展了MICP拌合法对红层泥岩填料的物理力学特性影响试验,通过相关试验研究了不同木钙、玄武岩纤维掺量下对MICP拌合法处理后红层泥岩填料的无侧限抗压强度、破坏特征、无荷膨胀率、耐崩解性的影响及其变化规律,揭示了木钙-玄武岩纤维协同微生物改良红层泥岩填料的作用机理。结果表明:(1)与MICP组相比,当木钙和玄武岩纤维掺量分别为3%和0.2%时,对试样的协同改良效果最优,其纵波波速提高了39.49%,无侧限抗压强度提升了134.55%,破坏时的峰值应变增大了32.34%,木钙-玄武岩纤维协同微生物作用能够显著提高红层泥岩填料的密实性、强度及其抵抗变形能力;(2)木钙-玄武岩纤维掺入后,红层泥岩填料的无荷膨胀率降低了53.84%~73.07%,最优掺量组试样的崩解性由中崩解改善为不崩解;(3)木钙-玄武岩纤维协同微生物改良红层泥岩填料的机制主要包括木质素聚合物的胶结填充作用、玄武岩纤维的加筋作用、木钙-玄武岩纤维对MICP协同促进作用等3个方面。本研究成果可为高铁路基红层泥岩填料的改良提供新的思路。
In order to enhance the microbial improvement effect of red mudstone filler,calcium lignosulfonate and basalt fiber were used as admixtures to cooperate with microorganisms to improve the red mudstone filler.The MICP mixing method was used to test the physical and mechanical properties of the red mudstone filler.The effects of different amounts of calcium lignosulfonate and basalt fiber on the unconfined compressive strength,failure characteristics,no-load expansion rate and disintegration resistance of the red mudstone filler treated by MICP mixing and their changing laws were studied through relevant experiments.The mechanism of calcium lignosulfonate-basalt fiber and microorganisms in the improvement of red mudstone filler was revealed.The results show that:(1)Compared with the MICP group,when the content of calcium lignosulfonate and basalt fiber is 3%and 0.2%respectively,the synergistic improvement effect of the sample is the best,the longitudinal wave velocity is increased by 39.49%,the unconfined compressive strength is increased by 134.55%,and the peak strain at failure is increased by 32.34%.The calcium lignosulfonate-fiber and MICP synergistic effect can significantly improve the compactness,strength,and deformation resistance of red mudstone filler.(2)After the addition of calcium lignosulfonate and basalt fiber,the no-load expansion rate of the red mudstone filler is reduced by 53.84%~73.07%,and the disintegration of the optimal content group sample is improved from moderate disintegration to no disintegration.(3)The mechanism of calcium lignosulfonate and basalt fiber synergistic with microorganisms to improve the red mudstone filler mainly includes three aspects:the cementing and filling effect of lignin polymer,the reinforcement effect of basalt fiber,and the synergistic promotion effect of calcium lignosulfonate and basalt fiber on MICP.The research results can provide new ideas for the improvement of red mudstone filler materials in high-speed railway subgrades.
作者
陈勇琪
肖瑶
邓华锋
朱文羲
黄小芸
Chen Yongqi;Xiao Yao;Deng Huafeng;Zhu Wenxi;Huang Xiaoyun(Key Laboratory of Geological Hazards on Three Gorges Reservoir Area,Ministry of Education,Yichang,Hubei 443002,P.R.China;College of Civil Engineering&Architecture,China Three Gorges University,Yichang Hubei 443002,P.R.China)
出处
《地下空间与工程学报》
北大核心
2025年第6期2005-2016,共12页
Chinese Journal of Underground Space and Engineering
基金
国家自然科学基金联合基金(U22A20600)
三峡大学人才科研启动基金(2024RCKJ021)
三峡库区地质灾害教育部重点实验室开放基金(2023KDZ15)。
关键词
红层泥岩填料
微生物加固
木质素磺酸钙
无侧限抗压强度
无荷膨胀率
red mudstone filler
microbial reinforcement
calcium lignosulfonate
unconfined compressive strength
no load expansion rate
