CAJ | 학술논문

针对北京地铁15号线新建奥林匹克公园站顺行密贴下穿大屯路隧道的施工技术难点，对传统泵吸反循环钻孔灌注桩施工设备进行改进，使其满足导洞内复杂环境下桩基施工的要求，并对施工工艺进行优化，保证施工安全和成桩质量。桩基施工完成后，通过自平衡法静载试验得到单桩竖向抗压承载力特征值，采用超声波透射法和低应变反射波法对大直径桩桩身完整性进行检测。试验和检测结果均表明，大直径桩均为Ⅰ类桩，桩身完整性良好，实测的单桩竖向抗压承载力特征值均满足设计要求。说明暗挖导洞内大直径桩成套施工技术能够满足成桩质量和效率的要求，保证工程的施工安全。
침대북경지철15호선신건오림필극공완참순행밀첩하천대둔로수도적시공기술난점，대전통빙흡반순배찬공관주장시공설비진행개진，사기만족도동내복잡배경하장기시공적요구，병대시공공예진행우화，보증시공안전화성장질량。장기시공완성후，통과자평형법정재시험득도단장수향항압승재력특정치，채용초성파투사법화저응변반사파법대대직경장장신완정성진행검측。시험화검측결과균표명，대직경장균위Ⅰ류장，장신완정성량호，실측적단장수향항압승재력특정치균만족설계요구。설명암알도동내대직경장성투시공기술능구만족성장질량화효솔적요구，보증공정적시공안전。
According to the construction technology difficulty of Olympic Park Station in Beijing Subway Line 15 underneath passing the Datun Road tunnel,the traditional construction equipment system of bored piles with the pump suction reverse circulation method was improved to meet the pile foundation construction requirements under the complex conditions in a drift and the construction technology was optimized to ensure the construction safety and the high quality of the completed piles. After completing the pile foundation construction,the characteristic values of the single pile vertical bearing capacity are obtained by self-balanced static load tests and the integrity of large-diameter pile are tested by using ultrasonic transmission method and low strain reflected wave method. T he test and inspection results showed that large-diameter piles are Ⅰ class and have good integrity,the measured characteristic values of the single pile vertical bearing capacity can meet design requirements,which means the improved construction technology of large-diameter pile in underground excavation drift could meet the needs of the construction quality,efficiency and safety.