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991.
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中钢天津响螺湾工程后压浆钻孔灌注桩施工技术 总被引：1，自引：0，他引：1
中钢天津响螺湾工程基础桩采用后压浆钻孔灌注桩,最大桩长达76 m,设计单桩承载力特征值达15000 kN。阐述该工程钻孔桩的施工工艺、施工中出现的问题和解决方法、孔口钢筋笼直螺纹对接技术、后压浆施工工艺。通过现场试验,全部桩为Ⅰ类桩,单桩承载力达到设计要求,极限承载力实测值最大为35000 kN,为工程桩的设计提供了可靠的技术参数。 相似文献
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Construction of seaside and underground wall bracing often uses stiffened deep cement mixed columns (SDCM). This research investigates methods used to improve the level of bearing capacity of these SDCM when subjected to cyclic lateral loading via various types of stiffer cores. Eight piles, two deep cement mixed piles and six stiffened deep cement mixing piles with three different types of cores, H shape cross section prestressed concrete, steel pipe, and H-beam steel, were embedded though soft clay into medium-hard clay on site in Thailand. Cyclic horizontal loading was gradually applied until pile failure and the hysteresis loops of lateral load vs. lateral deformation were recorded. The lateral carrying capacities of the SDCM piles with an H-beam steel core increased by 3-4 times that of the DCM piles. This field research clearly shows that using H-beam steel as a stiffer core for SDCM piles is the best method to improve its lateral carrying capacity, ductility and energy dissipation capacity. 相似文献
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Two major earthquakes in Alaska, namely the 1964 Great Alaska Earthquake and the 2002 Denali Earthquake, occurred in winter
seasons when the ground crust was frozen. None of the then-existing foundation types was able to withstand the force from the
lateral spreading of frozen crust. This paper presents results from the analysis of pile foundations in frozen ground overlying liquefiable
soil utilizing the Beam-on-Nonlinear-Winkler-Foundation (BNWF) (or p-y approach). P-multipliers were applied on traditional
sandy soil p-y curves to simulate soil strength degradation during liquefaction. Frozen soil p-y curves were constructed
based on a model proposed in a recent study and the frozen soil mechanical properties obtained from testing of naturally frozen
soils. Pile response results from the p-y approach were presented along with those from fluid-solid coupled Finite Element (FE)
modeling for comparison purpose. Finally, the sensitivity of pile response to frozen soil parameters was investigated and a brief
discussion is presented. 相似文献
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Experiments about working mechanism and mechanical characteristics of the DX model pile foundation under lateral dynamic and static loading were conducted by using a model system of the dynamic frozen ... 相似文献
999.
复合模量是计算复合地基沉降的关键参数,但求解出完全符合实际的精确解较困难。为此采用弹性理论中最小势能原理推求出复合模量上限值计算公式。此外,对影响复合模量上限值的几个主要参数如桩土压缩模量、土体泊松比、置换率等进行了分析,获得了一些定性的结论：上限值随着土体模量和置换率的增大而增大,复合模量取值应乘以1.1～1.4扩大系数。 相似文献
1000.