苗尾水电站片状砂板岩筑坝技术研究  

Research on Dam Construction Technology of Sheet Sandstone-Slate in Miaowei Hydropower Station

作　　者：鄢镜 黄泰仁 YAN Jing;HUANG Tai-ren(Power China Huadong Engineering Corporation Limited,Hangzhou 311122,China)

机构地区：[1]中国电建集团华东勘测设计研究院有限公司,浙江杭州311122

出　　处：《云南水力发电》2021年第7期50-57,共8页Yunnan Water Power

摘　　要：苗尾水电站大坝为砾质土心墙堆石坝,坝高131.3m,溢洪道位于大坝左岸,溢洪道开挖石料约1 000×10^(4)m^(3),上坝近且交通方便,是大坝堆石料填筑(约700×10^(4)m^(3))的首选料场。但是开挖料为片状砂板岩混合料,互层分布,软硬相间,难以筛选,混合料中的板岩呈扁平片状,粒形欠佳,可能存在碾压不密实、架空等现象,导致饱水后变形较大;同时也可能存在碾压后破碎率较高,细粒含量偏多,透水性差、变形模量偏低等情况。苗尾水电站片状砂板岩混合料筑坝技术研究是工程的关键技术问题之一。通过对片状砂板岩混合料的工程力学特性研究,揭示片状砂板岩混合料的力学和压实特性,掌握片状砂板岩混合料的工程特点和适用性,达到合理确定开挖料的上坝比例及坝体分区的目的,提出合理的施工参数,保证大坝永久安全稳定运行。Miaowei Hydropower Station is a gravel earth core rockfill dam with a dam height of 131.3m.The spillway is located on the left bank of dam and the excavated stone for spillway is about 1000×10^(4)m^(3).The spillway is the preferred material yard for dam rockfill filling due to its proximity to dam and convenient traffic.However,the excavation material is lamellar sandstone mixture with interbedded distribution,soft and hard phases,which is difficult to screen.The slate in the mixture is flat and lamellar,with poor grain shape.Some phenomena such as compaction,overhead may exist,resulting in large deformation after saturated water.At the same time,there may be high fracturing rate,more fine particles,poor water permeability and low deformation modulus after compaction.The technical research of sheet sandstone-slate mixture dam construction for Miaowei Hydropower Station is one of the key technical problems of the project.According to the research on the engineering mechanical characteristics of the flaky sandstone mixture,the mechanical and compaction characteristics of the flaky sandstone mixture are revealed,the engineering characteristics and applicability of flaky sandstone mixture are mastered,so as to reasonably determine the proportion of excavated material to dam and the partition of dam body,and reasonable construction parameters are put forward to ensure the permanent safe and stable operation of dam.

关 键 词：片状砂板岩 坝料试验 碾压试验 变形 监测 安全 

分 类 号：TV641.41[水利工程—水利水电工程] TV698.1