胶凝砂砾石坝填筑控制指标试验研究

Experimental study on control indicators for cemented sand and gravel dam construction

胶凝砂砾石坝在填筑中所用砂砾石料不洗筛,且骨料的含水率不一、级配分布广。为确定在设计配合比下的坝体压实填筑控制指标,开展了两种胶凝材料配比在3种铺料厚度和3种碾压遍数条件下的现场碾压试验。结果表明,在各种试验条件下,45cm和55cm铺料厚度均较65cm铺料厚度的压实更充分。根据28d强度值和碾压遍数与碾压后干密度的关系,最终形成了9项内容的施工控制参数。本研究为胶凝砂砾石坝填筑提供了技术控制参数,该成果对类似工程具有参考价值和推广意义。

In the construction of cemented sand and gravel dams,the use of uncleaned and unscreened sand and gravel materials,with varying moisture content and wide particle size distribution,is common.In order to investigate the control indicators for compacting the dam under the designed mix ratio,on-site compaction tests were conducted under three different bedding thicknesses and three levels of rolling passes for two types of cementitious materials.The results show that,under various test conditions,compaction is more thorough with bedding thicknesses of 45cm and 55cm compared to a thickness of 65cm.Based on the relationship between 28-day strength values,the number of rolling passes,and postcompaction dry density,nine construction control parameters are ultimately established.This research provides technical control parameters for the construction of cemented sand and gravel dams,and its findings have reference value and practical significance for similar engineering projects.