CAJ | 학술논문

为了准确掌握岛状多年冻土地区桥梁钻孔灌注桩的回冻时间及桩基回冻后的承载力，在岛状多年冻土地区选择2个试验地点，每个试验地点浇筑了2根15 m长的试验桩，并在其中一根试验桩处布设温度监测系统，采集桩基回冻过程中的温度数据，根据温度监测结果判断桩基回冻状态，在桩基完成回冻后进行静载与动测试验，测出桩基极限承载力。监测及试验结果表明：试验桩所在区域岛状多年冻土地温约为－1.9℃，桩基完成回冻后桩身内部温度与桩侧1 m处的土体温度变化趋势相同，相同深度处的温差小于0.1℃；用静载法实测出的各土层回冻后的桩侧摩阻力值修正高应变动测法桩–土力学模型中的土层参数，计算曲线与实测曲线拟合较好；动测与静载试验所得到的桩基极限承载力误差为3.91%，试验结果相符合。研究成果可为类似冻土条件下的桩基设计及承载力检测提供理论依据。
위료준학장악도상다년동토지구교량찬공관주장적회동시간급장기회동후적승재력，재도상다년동토지구선택2개시험지점，매개시험지점요축료2근15 m장적시험장，병재기중일근시험장처포설온도감측계통，채집장기회동과정중적온도수거，근거온도감측결과판단장기회동상태，재장기완성회동후진행정재여동측시험，측출장기겁한승재력。감측급시험결과표명：시험장소재구역도상다년동토지온약위－1.9℃，장기완성회동후장신내부온도여장측1 m처적토체온도변화추세상동，상동심도처적온차소우0.1℃；용정재법실측출적각토층회동후적장측마조력치수정고응변동측법장–토역학모형중적토층삼수，계산곡선여실측곡선의합교호；동측여정재시험소득도적장기겁한승재력오차위3.91%，시험결과상부합。연구성과가위유사동토조건하적장기설계급승재력검측제공이론의거。
To accurately know the refreezing time and capacity of the bridge bored pile constructed in polygonal permafrost regions,two test sites were chosen. Within each site,two 15 m test piles were built. The temperature monitoring system was established in one of the two sites to record and monitor the pile refreezing process. Based on the refreezing condition,static load and dynamic load tests were performed to determine the bearing capacity of the pile. Test results indicate that the mean permafrost temperature is-1.9℃. The trend of temperature change within the pile in refreezing process is similar to that of the permafrost temperature change 1 m beside the pile, which indicates that the difference of temperature change is smaller than 0.1℃. The calculated pile capacity fits well with the testing data by introducing the refreezing pile lateral frictional parameter to modify the soil mechanical model. The capacity error obtains from static load test and dynamic load test is 3.91%,which matches the test results. This reacher provides an evidence to design and test the pile foundations in permafrost areas.