The bearing behavior and load transfer mechanism of the rock-socketed short pile were studied by the experimental and FEM analysis of two case history of 11 single short piles in weathered rock foundation of Qingdao. The influences of aspect ratio (L/d), rock-socketed length (hr) and bedrock strength (Ep/Er) on bearing behaviors of rock-socketed short were discussed by FEM analysis of bearing characters of large-diameter rock-socketed short piles. The results show that the ultimate bearing capacity of rock-socketed short is higher, and settlement is smaller, which can be satisfied with engineering demands and has high security reserves. Moreover, the change of ultimate bearing capacity of single pile is not obvious with the increase of pile lengths, which proves that the 11 piles are of strong end bearing properties. The pile side friction peak decreases with the increase ofL/d; the pile top settlement increases with the increase ofL/d. Under different rock-socketed lengths, the attenuation law of axial force is consistent; the pile top settlement decreases with the increase ofhr, and the ratio of base resistances to the bearing capacities (Qp/Qu) decreases with the increase ofhr. The pile top settlement increases with the increase ofEp/Er,Qp/Qu increases with the increase of Ep/Er. The research results can provide references for rock-socketed short pile design in similar geological conditions.%通过对青岛地区风化岩地基2个工程11根短桩的原位测试及有限元模拟分析,研究嵌岩短桩的承载性状和荷载传递特征.对大直径嵌岩短桩的承载性状进行有限元模拟,探讨长径比、嵌岩深度及基岩强度对嵌岩短桩承载性能的影响.研究结果表明:风化岩地基中的嵌岩短桩极限承载力高,沉降小,能够满足工程需求并具有较高的安全储备;单桩极限承载力随着桩长的增加变化并不显著,表现出极强的端承性状.嵌岩段桩侧摩阻力峰值随长径比的增大逐渐减小,桩顶沉降随长径比增加而增大;不同的嵌岩深度下,桩身轴力衰减的规律基本相同,随嵌岩深度的增加,桩顶沉降逐渐减小,端阻力在承载力中所占比例(Qp/Qu)逐渐减小;桩顶沉降随桩岩刚度比(Ep/Er)的增加而逐渐增大,而端阻分担的荷载比随Ep/Er的减小逐渐增大.
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