基于落锤式弯沉仪的路基表面弯沉试验技术要点分析  

Analysis on Key Points of Subgrade Surface Deflection Test Technology based on Falling Weight Deflectometer

作　　者：刘锋 李善强 陈小辉 许新权 刘新海 LIU Feng;LI Shan-qiang;CHEN Xiao-hui;XU Xin-quan;LIU Xin-hai(Guangdong HualuTransport Technology Co.Ltd.,Guangzhou 510420,China;Guangdong Jiaotong Technology Research and Development Co.Ltd.,Guangzhou 510420,China;Research and Development Center on Road Transport Safety and Emergency Support Technology&Equipment,Ministry of Transport,Guangzhou 510420,China)

机构地区：[1]广东华路交通科技有限公司,广州市510420 [2]广东交科技术研发有限公司,广州市510420 [3]公路交通安全与应急保障技术及装备交通运输行业研发中心,广州市510420

出　　处：《公路》2024年第10期22-28,共7页Highway

基　　金：广东省基础与应用基础研究基金项目,项目编号2022A1515011326;广东省交通集团项目,项目编号JT2022YB12;广东省重点领域研发计划项目,项目编号2022B0101070001。

摘　　要：依托广东省内某高速公路路基工程,开展落锤式弯沉仪路基表面弯沉试验技术要点研究。选定长度为300 m的填方试验区域1和长度为400 m的填挖结合试验区域2开展试验研究。根据编制的试验方案,于两个试验区域分别布置了多条FWD测线,基于获得的路基表面弯沉数据,开展了FWD设备量程要求、FWD第1锤数据取舍、FWD同一测点加载次数、FWD荷载级位、测点间隔距离、土质类型和路基类型等影响因素的分析。研究结果显示,FWD用于路基表面弯沉试验时,其对路基土质类型和路基类型有较强的敏感性;但FWD用于路基弯沉试验时,其量程需满足一定要求,同时,同一测试点第1锤数据需舍弃,以5次锤击数据的后4锤数据的平均值作为该测试点的弯沉值;测试点间隔距离对于路段的代表值影响较小,但单点弯沉数据对于评价路段压实均匀性是有利的;不同FWD荷载级位下的路基表面弯沉值存在差异,其弯沉大小并非与荷载呈现简单的正比关系。因此,FWD用于路基表面弯沉试验与用于路面弯沉试验有一定差异,需满足一定技术要求。Based on a highway subgrade project in Guangdong Province,the key technical points for subgrade surface deflection test are studied by using the falling weight deflectometer.The filling test area No.1 with a length of 300 m and the combined test area No.2 with a length of 400 m are selected to carry out the experimental research.According to the prepared test plan,several FWD lines are arranged in the two test areas.Based on the obtained subgrade surface deflection data,an analysis is conducted on factors affecting the FWD equipment range requirements,FWD first hammer data selection,FWD loading times at the same measurement point,FWD load level,measurement point spacing distance,soil type,and roadbed type.The research results show that the results show that FWD is sensitive to the type of subgrade soil and the type of subgrade when it is used in the subgrade surface deflection test.However,when FWD is used in subgrade deflection test,its range must meet certain requirements,and the first hammer data at the same test point must be discarded,the deflection value of the test point is taken as the average value of the last 4 hammers of the 5 hammering data.The distance between test points has a small impact on the representative value of the road section,but single point deflection data is beneficial for evaluating the compaction uniformity of the road section.The surface deflection of subgrade under different FWD load levels is different,and the deflection is not directly proportional to the load.Therefore,there is a certain difference between FWD used for roadbed surface deflection test and pavement deflection test,and it must meet certain technical requirements.

关 键 词：道路工程 落锤式弯沉仪 路基弯沉 技术要点 

分 类 号：U416.1[交通运输工程—道路与铁道工程] U416.06