高土石坝心墙砾石土料自动掺合系统研究

Study on automatic mixing system for gravel-earth material of core-wall for high earth-rockfill dam

针对平铺立采传统工艺存在自动化水平及生产效率低、掺合场地大且经济效益差等问题,为提升高土石坝心墙砾石土料掺合质量和效果,借鉴水泥生产掺合理论和工艺,依托坝高312 m的双江口水电站砾石土心墙堆石坝工程,全面研究了心墙砾石土料自动化掺合理论、掺合装置、配料及计量系统,提出了采用犁式搅拌装置的卧式强力掺合机进行掺合的设计依据和参数,以及掺合系统精准计量方式和装置参数。通过三维模拟计算分析可知:掺合系统生产能力为1 080 t/h,掺和次数可达4次,土料计量精度可控制在0.5%以内,砾石料计量精度可控制在1%以内,掺合效果达到预期目标,满足设计要求。该研究首次在水电行业提出了土石坝砾石土心墙料自动掺合理论和相关装置设计参数,为300 m级高土石坝心墙砾石土料自动掺合奠定了理论和技术基础,其成果可供其他类似工程参考借鉴。

Aiming at the problems of lower automation level and production efficiency,larger mixing yard,poor economic benefit,etc. in the conventional technology of horizontally placing and vertically exploiting,the theory,mixing equipment,batching and measuring system of the automatic mixing system of gravel-earth material for core-wall are fully studied herein in accordance with the construction of the gravel-earth core rockfill dam with the height of 312 m for Shuangjiangkou Hydropower Station according to the reference from the mixing theory and technology of cement production,so as to enhance the mixing quality and effect of the gravel-earth material for construction of the core-wall for earth-rockfill dam,and then the design basis and parameters for carrying out the mixing by powerful horizontal mixer equipped with plough-type mixing device as well as the accurate measuring mode and the device parameters for the mixing system are put forward. It is known through the 3-D simulative analysis concerned that the production of the mixing system is 1 080 t/h,the mixing times can reach to 4,the measuring accuracy of the earth material can be controlled within 0. 5% and the measuring accuracy of the gravel material can be controlled within 1%,thus the mixing effect reach the expected goal and meet the relevant design requirement. The theory of the automatic mixing of the gravel-earth material for the construction of the core-wall for earth-rockfill dam and the design parameters of the relevant equipment are initially proposed by this study,which lays a theoretical and technical basis for mixing of the gravel-earth material for the construction of the core-wall for 300 m-grade high earth-rockfill dam and the result can provide a reference for the other similar projects as well.