CAJ | 학술논문

以黄土地区桩基浸水试验为代表的桩身内力长期监测过程中,桩身混凝土除发生弹性应变外还会发生蠕变,以往工作中往往忽略了混凝土在轴力长期作用下蠕变对测试结果的影响,但蠕变真实存在,它对内力测试结果的影响程度以及如何消除其影响值得研究.根据现场实测试验资料对比分析表明,长时间的桩基内力测试应考虑桩身蠕变的影响;基于混凝土蠕变的相关理论,推导了从实测应变中扣除桩身蠕变的公式;从消除蠕变影响角度分析了黄土桩基浸水试验中应采取的措施,其关键技术是控制试验桩的混凝土强度等级,在桩顶附近设置标定段,并保持标定段混凝土的温度和湿度恒定,且与下部桩体一致,获得具有代表性的蠕变度函数曲线.
이황토지구장기침수시험위대표적장신내력장기감측과정중,장신혼응토제발생탄성응변외환회발생연변,이왕공작중왕왕홀략료혼응토재축력장기작용하연변대측시결과적영향,단연변진실존재,타대내력측시결과적영향정도이급여하소제기영향치득연구.근거현장실측시험자료대비분석표명,장시간적장기내력측시응고필장신연변적영향;기우혼응토연변적상관이론,추도료종실측응변중구제장신연변적공식;종소제연변영향각도분석료황토장기침수시험중응채취적조시,기관건기술시공제시험장적혼응토강도등급,재장정부근설치표정단,병보지표정단혼응토적온도화습도항정,차여하부장체일치,획득구유대표성적연변도함수곡선.
@@@@Besides elastic strain, creep would also occurred in long-term pile stress test represented by pile immersion test in loess regions for concrete pile;and the influence of creep occurred under long-term axial stress was usually be overlooked in the past when calculating stress of pile body. But creep is a real existence, influence degree of creep and how to eliminate its effect are worth studying. Based on comparative analysis of field test data, how the concrete creep affect the analytical results of pile stress is studied;and the conclusion shows that the overlook of concrete creep will lead to wrong distribution rules of axis force and friction. A formula, which calculates axial force of pile and can eliminate the creep influence, is derived from some basic theory on creep. Some measures needing be taken in pile immersion test of loess regions to attain representative creep curve are presented;mainly include:controlling the concrete strength grade of test pile, setting calibration section near pile top and keeping concrete’s temperature and moisture constant in this section and are in the same with lower pile.