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In order to solve the problem of ground collapse and mudslide caused by the accumulation of loose moraine on the surface of Pulang copper mine in the process of mining, this article prepared a solidified material to solidify moraine with water glass composite ester curing agent. The compressive strength of moraine solidified body was studied, and the consolidation mechanism of water glass composite ester curing agent for consolidating moraine was explored through XRD, FTIR, DSC-TG and SEM. The results show that the moraine solidified body 28 d compressive strength can reach up to 2.05 MPa, indicating good consolidation performance. Under the action of ester curing agent, the hydrolysate of water glass reacts with the hydrolysate of ester curing agent to produce sodium acetate and silicon gel, and silicon gel plays a role in filling the gap between moraine particles and cementing moraine particles. [ABSTRACT FROM AUTHOR]

The geological environment of Pulang copper mine is fragile, and collapse pits will be formed on the surface during mining. When continuous rainfall occurred, the surface moraine is saturated in water absorption and flows into the mine outlet, causing debris flow disaster in the underground. In response to this problem, experiments on the influencing factors and influencing rules about the gelling time of sodium silicate-curing agent slurry and the strength of moraine soil consolidation are carried out. The experimental results show that the slurry gels faster as the concentration of the catalyst increases in the mixture of sodium silicate-curing agent. The gelation time of sodium silicate-curing agent slurry decreases first and then increases with the concentration of curing agent increasing. Meanwhile, with the increase of sodium silicate s concentration it will spend less time for sodium silicate-curing agent slurry gelling. In addition, both the concentration of sodium silicate and the concentration of curing agent have a positive effect on the compressive strength of the moraine consolidation body. The experimental results can provide a theoretical basis for the grouting solidification of surface moraine. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There are abundant moraine soil sources distributed in the Qinghai-Tibet Plateau of China, with complex historical causes, changeable material structure, and large differences in mechanical properties. Moraine landslide often occurs under the action of rainfall and ice and snow melting. The debris of landslide enters the gully and mixes with water flow, which is very easy to produce the moraine landslide--debris flow--dammed lake disaster chain, which is the key and difficult point of disaster prevention and reduction in the plateau. In recent years, the Sichuan--Tibet railway project and major hydropower development in Tibet have faced a great threat from the moraine landslide--debris flow--dammed lake disaster chain. It is a major national demand to improve the capacity of disaster prevention, reduction and relief. Moraine landslide--debris flow--dammed lake--dam-breaking flood is a chain disaster process of cascade amplification, which involves complex dynamic evolution mechanisms such as landslide initiation, movement behavior transformation, erosion amplification along the process, multi-stage river blocking superposition, and dam break water-sediment coupling. Especially under complex meteorological conditions, there are some problems such as unclear mechanism, inaccurate model, and lack of simulation technology. It is urgent to carry out the research on the complex dynamic mechanism, control theoretical model, and whole process numerical simulation of moraine landslide--debris flow--dammed lake disaster chain process. Combined with the research status at home and abroad, five research contents are further proposed: 1) Evolution of mechanical properties of moraine soil under complex meteorological conditions. 2) Dynamic disaster process and migration model of moraine landslide--debris flow. 3) Formation mechanism and simulation of moraine landslide--debris flow--dammed lake. 4) Mechanism of erosion and outburst of moraine dam and the process of flow channel expansion. 5) Mechanism of water-sediment interaction in the downstream channel and the simulation of flood evolution. Many preliminary explorations and research work have been carried out to preliminarily reveal the migration of moraine landslide debris flow and multi-stage river blocking mechanism, a dam break evolution model that can consider water erosion and intermittent collapse of the broken slope has been built, and the simulation method of moraine landslide--debris flow--dammed lake disaster chain evolution process has been discussed. The results lay a foundation for further understanding of the complex dynamic mechanism of the moraine landslide--debris flow--dammed lake disaster chain process, constructing the control theoretical model and developing the whole process numerical simulation system. And the results are expected to provide a theoretical basis for the mechanism of moraine landslide--debris flow--dammed lake disaster chain and technical support for non-engineering risk reduction and emergency disposal decision-making. [ABSTRACT FROM AUTHOR]

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)