CAJ | 학술논문

文章考虑了土体力学特性，以及桩身材料性质、桩长与桩径（含扩底直径）、桩顶埋深、桩顶卸载与加载、群桩效应等诸多因素的影响，结合工程经验给出了计算扩底抗拔桩极限承载力的半经验半理论方法；根据扩底抗拔桩破坏面位置不同，将扩底抗拔桩破坏模式分为三类（即破坏面延伸至地表的整体剪切破坏、破坏面介于地表与扩孔段之间的局部剪切破坏与破坏面位于扩孔段附近的冲剪破坏），推导出了整体剪切破坏模式的极限平衡状态方程；并依据扩底抗拔桩轴对称条件与土体抗拉强度小的力学特征，给出了求解整体破坏面的微分筒数值解法；利用经验法估算了局部剪切破坏、冲剪破坏模式下的端阻力，进而给出了任意土层中扩底抗拔桩承载力计算步骤与方法；最后，结合一足尺试验的计算分析与承载力测试比较，验证了计算方法的可靠性与精确度。
문장고필료토체역학특성，이급장신재료성질、장장여장경（함확저직경）、장정매심、장정사재여가재、군장효응등제다인소적영향，결합공정경험급출료계산확저항발장겁한승재력적반경험반이론방법；근거확저항발장파배면위치불동，장확저항발장파배모식분위삼류（즉파배면연신지지표적정체전절파배、파배면개우지표여확공단지간적국부전절파배여파배면위우확공단부근적충전파배），추도출료정체전절파배모식적겁한평형상태방정；병의거확저항발장축대칭조건여토체항랍강도소적역학특정，급출료구해정체파배면적미분통수치해법；이용경험법고산료국부전절파배、충전파배모식하적단조력，진이급출료임의토층중확저항발장승재력계산보취여방법；최후，결합일족척시험적계산분석여승재력측시비교，험증료계산방법적가고성여정학도。
Considering the influences of such factors as soil mechanical characteristics, pile material properties, pile length and pile diameter (including the expanded pedestal diameter), depth of the pile top, and unloading and loading around the pile top and pile group effect, combined with engineering practices, an empirical-theoretical calculation method for the ultimate bearing capacity of an expanded pedestal uplift pile is proposed in this paper. Based on different positions of the failure surface of the expanded pedestal uplift pile, the failure mode of the expanded pedestal uplift pile is divided into three types: entire shearing failure from the failure surface extending to the ground surface, local shearing failure of the failure surface between the ground surface and borehole-expanded section, and punching shear failure of the failure surface near the borehole-expanded section. An ultimate equilibrium state equation under the entire shearing failure mode is derived. According to the axial symmetry conditions of the expanded pedestal uplift pile and the mechanical characteristics of the lower soil tensile strength, a differential cylinder numerical solution is given regarding the entire failure surface. By using the empirical method to estimate the end resistances under the local shearing failure mode or punching shear failure mode, the calculating procedure and method for the ultimate bearing capacity of the expanded pedestal uplift pile in any soil layer is put forward. Finally, the reliability and accuracy of the calculating method is verified through a comparison between the calculated ultimate bearing capacity and the measured one in a full-scale test.