摘要
以贵州盘兴高速公路超大粒径填石高路堤强夯加固工程为例,基于强夯加固后路堤不同深度范围内填料密实程度变化规律和强夯加固夯击能量传播衰减特征,对填石高路堤强夯有效加固深度进行了综合研究.同时,基于体应变方程推导了考虑路堤强夯加固后夯坑深度和填料压实密度控制要求的强夯有效加固深度计算公式.开展现场压实试验,获得了压实能量作用下路堤填料压实密度与静土压力增量的函数关系.开展现场强夯加固试验,分析了路堤表面位移及内部动、静应力随夯击次数的变化规律.结果表明:压实能量作用下路堤填料压实密度与静土压力增量有较强的相关性.填石高路堤夯击8次后夯坑深度达932 mm,夯坑附近路堤表面最大隆起值达50 mm.夯击能量作用下路堤深处动应力峰值和静土压力增量随深度增加衰减较快,夯坑附近路堤表面隆起值随与夯锤边缘距离增加衰减更加显著,强夯竖向有效加固深度和横向有效加固半径分别大约为5.0 m、2.5 m.基于不同夯击次数下强夯有效加固深度实测数据,拟合了建立的填石高路堤强夯有效加固深度计算公式的修正系数,进一步建立了综合考虑强夯加固横向和竖向作用效应及加固质量控制要求的有效加固深度优化计算公式.
Taking the dynamic compaction reinforcement project of the super large particle size high stonedfilled embankment of Pan-Xing highway of Guizhou province as an example,the effective reinforcement depth of high stoned-filled embankment was comprehensively studied based on the variation law of embankment compacted fill density with depth after dynamic compaction and the attenuation characteristics of tamping energy propagation of dynamic compaction.Meanwhile,a calculation formula for effective reinforcement depth of dynamic compaction was derived based on the volumetric strain equation considering the crater depth and compacted fill density control requirements.A field compaction test was carried out to obtain the functional relationship between the compacted fill density and static soil pressure increment under the compaction energy.Additionally,a field dynamic compaction test was carried out to analyze the variation laws of embankment surface displacement and the change of dynamic and static stress inside the embankment with the tamping times.The results indicate a strong correlation between the compacted fill density and static soil pressure increment under the compaction energy.The crater depth reached 932 mm,and the maximum embankment surface uplift near the crater reached 50 mm after eight tamping times.The peak value of dynamic stress and the static soil pressure increment in the depths of the embankment decreases rapidly with the depth,and the embankment surface uplift near the crater decreases more sharply with the increase of distance from the edge of the crater.The vertical effective reinforcement depth and horizontal effective reinforcement radius of dynamic compaction are about 5.0 m and 2.5 m,respectively.The modified coefficient of the established calculation formula for effective reinforcement depth of dynamic compaction was fitted based on the measured data of effective reinforcement depth under different tamping times.Furthermore,the effective reinforcement depth optimization formula considering the horizontal and vertical action effects of dynamic compaction and the reinforcement quality control requirements was established.
作者
徐平
侯伟琦
乔世范
董辉
罗正东
XU Ping;HOU Weiqi;QIAO Shifan;DONG Hui;LUO Zhengdong(College of Civil Engineering,Xiangtan University,Xiangtan 411105,China;School of Civil Engineering,Central South University,Changsha 410075,China;Key Laboratory of Geotechnical Mechanics and Engineering Safety of Hunan province,Xiangtan University,Xiangtan 411105,China)
出处
《湖南大学学报(自然科学版)》
北大核心
2025年第5期141-153,共13页
Journal of Hunan University:Natural Sciences
基金
国家自然科学基金资助项目(42272304)
湖南省教育厅资助项目(22C0046)
湘潭大学博士科研启动项目(21QDZ27)。
关键词
道路工程
填石高路堤
有效加固深度
压实密度
静土压力增量
强夯施工参数
road engineering
high stone-filled embankment
effective reinforcement depth
compacted fill density
static soil pressure increment
construction parameters of dynamic compaction
