水泥稳定碎石基层预切缝结构力学仿真研究  

Structural Mechanics Simulation Study on Pre-Cutting Joints in Cement Stabilized Macadam Base

作　　者：陈毅国 CHEN Yiguo(China Railway 19th Bureau Group 3rd Engineering Co.Ltd.,Shenyang Liaoning 110136,China)

机构地区：[1]中铁十九局集团第三工程有限公司,辽宁沈阳110136

出　　处：《铁道建筑技术》2025年第1期17-21,共5页Railway Construction Technology

基　　金：中铁十九局集团有限公司科技研究开发项目(23-Z02)。

摘　　要：为研究水泥稳定碎石基层预切缝技术对基层结构受力的影响,基于热传导与热力学理论,利用COMSOL软件建立水泥稳定碎石基层有限元模型,耦合固体传热、辐射换热以及固体力学,模拟养生期水泥稳定碎石的干燥收缩与温度收缩,并对比预切缝处治前后基层收缩应力分布情况。首先,通过二维模型计算得到水泥稳定碎石基层的收缩开裂间距,以此确定预切缝间距。其次,建立三维模型,进行温度场模拟并计算收缩应力,结果表明,基层顶部中轴处产生最大收缩应力,开裂风险较大。最后,对模型设置预切缝,与未切缝模型对比,预切缝处治后基层结构内部收缩应力得到了一定释放,基层1/4板长处出现最大应力。处治后基层底部应力显著增大,同时在预切缝底部出现应力集中,表明切缝在收缩作用下会继续扩展,最终产生贯穿基层的预裂缝。To investigate the impact of pre-cutting joints technology on the stress distribution in the cement-stabilized crushed stone base structure,a finite element model of the cement stabilized base was established using COMSOL software based on heat conduction and thermodynamic theory.The model coupled solid heat transfer,radiative heat exchange,and solid mechanics to simulate both drying shrinkage and temperature shrinkage during the curing period of the base course.A comparative analysis of the shrinkage stress distribution before and after pre-cutting joints treatment was conducted.Firstly,a two-dimensional model was used to calculate the shrinkage cracking distance of the base,leading to a selection of the pre-cutting joints distance.Secondly,a three-dimensional model was developed to simulate the temperature field and calculate shrinkage stress.Results indicated that the highest shrinkage stress occurred at the central axis of the surface of the base,indicating a high risk of cracking.Finally,after incorporating pre-cutting joints into the model,a comparison with the untreated model demonstrated a partial release of internal shrinkage stress,with the maximum stress occurring at one-quarter of the slab length.After treatment,stress levels at the bottom of the base increased significantly,with stress concentration observed at the bottom of the pre-cutting joints,indicating that the joint would continue to propagate under shrinkage effects,ultimately leading to a pre-crack that penetrates the base layer.

关 键 词：水泥稳定碎石基层 预切缝 温度场 温度应力 

分 类 号：U416.214[交通运输工程—道路与铁道工程]