CAJ | 학술논문

为研究正循环成孔、螺旋钻成孔两种施工工艺下桥桩极限承载力,通过对现场静载荷试验进行有限元数值模拟,确定桩基极限承载力及桩侧摩阻力分布,将理论计算值、试验实测值及模拟计算值对比分析。分析结果表明,桩-土界面引入无厚度Goodman摩擦单元,并考虑地应力平衡,能较好模拟桩土真实状态;正循环成孔桩初期的极限承载力较螺旋钻成孔桩小,经过桩周土较长时间的固结,其极限承载力接近于螺旋钻成孔极限承载力;采用螺旋钻成孔的情况下,古土壤和老黄土极限侧摩阻力推荐值为75 kPa。
위연구정순배성공、라선찬성공량충시공공예하교장겁한승재력,통과대현장정재하시험진행유한원수치모의,학정장기겁한승재력급장측마조력분포,장이론계산치、시험실측치급모의계산치대비분석。분석결과표명,장-토계면인입무후도Goodman마찰단원,병고필지응력평형,능교호모의장토진실상태;정순배성공장초기적겁한승재력교라선찬성공장소,경과장주토교장시간적고결,기겁한승재력접근우라선찬성공겁한승재력;채용라선찬성공적정황하,고토양화로황토겁한측마조력추천치위75 kPa。
In order to research the ultimate bearing capacity of the bridge-pile under the different construction processes which are normal circulation and spiral drilling,the value of ultimate bearing capacity and the distribution of the shaft friction resistance along the pile were obtained by the finite element numerical simulation based on the static load tests in site,and the simulation value was compared with the theoretical research value and measured value.The analysis results show that with the introduction of no-thickness Goodman friction unit and consideration of the balance of geostatic,the true state of pile-soil coupling can be simulated well by the finite element,and the ultimate bearing capacity under the normal circulation drilling is less than that under the spiral drilling at the initial stage,but the values can be close to each other in two means with a long time solidification.Under the spiral drilling,the pile-skin friction value recommended for ancient soil is 75 kPa.