首页期刊在线 2023年（第26卷）第3期

高含水率盾构废弃泥浆固化及强度特性研究

孟凡伦

Research on Solidification and Strength Characteristics of Shield Waste Mud with High Moisture Content

MENG Fanlun

作者信息:

中铁十四局集团大盾构工程有限公司， 211800, 南京
Affiliation:

China Railway 14th Bureau Group Large Shield Engineering Co., Ltd., 211800, Nanjing, China
关键词:

盾构隧道;废弃泥浆;固化剂;强度特性;微观机理
Key words:

shield tuanel;waste mud;curing agent;strength characteristics;micro mechanism
DOI:

10.16037/j.1007-869x.2023.03.029
中图分类号/CLCN:

U455
栏目/Col:

研究报告

摘要:

泥水盾构隧道施工会产生大量废弃泥浆，易引起环境污染等问题。为了提高废弃泥浆的力学性能，以济南某隧道泥水盾构施工过程产生的废弃泥浆为研究对象，研制了一种新型固化剂，以解决废弃泥浆再利用问题。在室内制作水泥固化土及新型固化土试样进行强度特性测试，并用扫描电镜对试样的微观结构和孔隙特征进行了研究。研究结果表明：当水泥掺量为15%时，新型固化土7 d抗压强度约为水泥固化土的35倍；外掺剂的最佳掺入比为水泥掺量的12%，可提高固化土的早期抗压强度及抗剪强度；新型固化土中生成了水化硅酸钙、水化铝酸钙等水化产物，形成了较好的骨架结构；废弃泥浆属于黏塑性宾汉流体，固化过程中发生了聚并和固化等复杂作用，逐渐向弹塑性流体过渡。

Abstracts:

A large amount of waste mud are produced in the slurry shield tunnels construction, easily causing problems such as environmental pollution. To improve the mechanical properties of the waste mud, taking the waste mud produced in the slurry shield construction of a tunnel in Jinan as research object, a new type of curing agent is developed to resolve the waste mud recycle issue. Strength characteristics test is carried out on indoor-produced samples of cement solidified soil and new type solidified soil, and the microstructure and pore characteristics of the samples are studied by SEM (scanning electron microscope). The results show that: when the cement content is 15%, the 7 d compressive strength of new type solidified soil is about 35 times that of cement solidified soil; the best ratio of the external admixture is 12% of the cement content, so that the early-stage compressive strength and the shear strength of the solidified soil will be improved. Hydration products are formed in the new type solidified soil, such as calcium silicate hydrate and calcium aluminate hydrate, which forms a relatively good skeleton structure. The waste mud is a Bingham viscoplastic fluid with complex effects such as coalescence and solidification occurring during the solidification process, and gradually transforms to elastoplastic fluid.