振冲碎石桩处理液化地基实例分析

一、工程概况及场地地质条件 杭州复兴地区11号地块住宅小区为杭州市抗咸安置小区。该小区位于杭州复兴街海月桥与洋泮桥之间。紧靠钱塘江边。小区内沿街部分为七层商住楼,其余均为七层普通住宅。 根据地质勘察资料,该小区属于古钱塘江河漫滩工级阶地,地基在七度地震烈度下,场地中松散     

振冲碎石桩处理液化地基的设计与施工

介绍采用振冲碎石桩处理液化地基并提高地基承载力的工程实例，对有关地基处理设计和施工工艺参数的确定进行了分析和探讨。     

振冲碎石桩施工技术

振冲碎石桩是利用在地基中就地振制的碎石快速加固松软地基的方法。近几年来在高层建筑地基的加固及处理中也得到了广泛地应用。它具有技术可靠、设备简单、操作技术易于掌握、施工简便快速、工期短、既不用水泥,又不用钢材,加固后地基承载力有显著提高等优点。适用于中、粗砂和部分细砂或粉砂土地基、特别适用于沿海地区的砂质土地基,所以在海南地区也得到较为广泛地应用,并且取得了良好的经济效果。 1 工程概况 海口市府城皇家公寓楼,设计为12层,框架结构,总建筑面积为6000多m~2。据地质钻探报告提供的资料,地基为中、细砂及软弱性粘土层,局部地方表面有淤泥层,地下水位较高。因此,经湖南省建筑设计院海南分院设计采用振冲碎石桩加固地基,加固后复合     

振冲碎石桩施工技术研究

从实际的某个项目出发，提出了在地基处理中选中振冲碎石桩的方案，并给出了振冲碎石桩体设计的方法，探讨了设计中存在的问题和解决方式，并给出了它的施工方案。     

振冲碎石桩部分消除地基液化的工程应用

本文介绍了振冲碎石桩加固地基的机理,结合具体工程,总结了振冲碎石桩在部分消除地基液化方面的工程应用、设计计算方法及其在地基加固处理中的优点。     

和安花园振冲碎石置换桩消除砂土液化的经验

通过振冲置换碎石桩在处理液化地基中的工程实践,论述了振冲置换碎石桩法的施工工艺及处理效果,证明用于处理饱和砂土及粉土液化及提高地基上的承载力是可行的。     

变桩长振冲碎石桩处理液化地层实录

在进行液化地层复合地基处理时,采用振冲碎石桩处理是一种有效的手段,以往有关的介绍也不在少数,但是目前的规范,一般都要求碎石桩的桩长是必须穿过液化地层。本文通过有关学者的建议,将振冲碎石桩进行变桩长设计,有50%的桩长穿过液化地层,另外50%的桩长不穿过,两种桩长间隔设置,在施工完毕后,进行复合地基承载力检测和液化地层液化指数判别,结果显示,该种布桩形式可以起到消除液化的作用,并且处理后的复合地基承载力也能够满足设计要求。     

浅谈振冲碎石桩施工技术

振冲碎石桩作为一种软基处理方法,用于加固各种软土地基,尤其适用于组成性质不同的多层软弱地基。软土地基经振冲处理后可加快固结,减少沉降,提高强度指标、抗震性能。本文结合实际工程,对振冲碎石桩施工及管理措施进行探讨,并于工程施工中所遇到的具体难题,提出解决措施,对保证工程施工质量,节约基建投资,有相应的参考价值。     

振冲碎石桩在加固处理砂土液化地基中的应用

本文以福建沿海某道路工程砂土液化地基的加固处理为例,着重介绍了振冲碎石桩加固处理可液化地基的机理、技术参数及施工工艺。通过标准贯入试验、重型动力触探试验、载荷试验等原位测试方法,对桩间砂土层的液化消除效果、桩间砂土密实度、桩体施工质量及复合地基的承载性能进行了分析评价,试验所得结果可供类似工程借鉴。     

振冲碎石桩在软弱液化地层中应用试验研究

某拟建电厂工程通过采用振冲碎石桩复合地基的处理方法,开展了软弱液化地基治理的现场试验研究,试桩施工结束后,采用载荷试验、标准贯入试验、土工试验、超重型动力触探试验等原位测试方法,对桩间土、桩体及复合地基的承载性能、变形参数及液化处理效果进行了评价和分析,取得了大量可靠的试验数据,对类似工程具有一定的参考价值。     

Filtration performance of geotextile encasement to minimize the clogging of stone column during soil liquefaction

Stone columns, which are frequently employed to stabilize the liquefiable soil, are susceptible to accumulation of soil particles. The progressive accumulation of the soil particles causes clogging of the stone column which decreases its drainage capacity. The stone column can be encased with geotextile to sustain its long term drainage function. The encasement prevents the movement of the soil particles into the stone pores. In the present paper, a mathematical model is presented to assess the filtration performance of the geotextile encasement to prevent the clogging. The filtration capacity of the geotextile is related to its maximum pore size, porosity and soil characteristics. It is observed that the encased stone column dissipates the excess pore pressure at a faster rate compared to the stone column without encasement. The peak maximum excess pore water pressure (U_max) is not significantly affected due to selection of the opening size of the geotextiles for single earthquake. However, the opening size can significantly affect the peak U_max value for multiple earthquakes. Depending on the capture coefficient of the stone column, the clogging can be fully prevented for higher hydraulic gradient if geotextile with maximum opening size in between D₁₀ to D₅ is used as encasement.     

振冲碎石桩在砂土地基处理中的应用

根据内蒙地区砂土地基的地质特性,详细阐述了振冲碎石桩处理砂土地基的适宜性,并针对施工中存在的问题,提出了相应的质量控制措施,以期为类似工程的施工提供参考借鉴。     

Effect of clogging of stone column on drainage capacity during soil liquefaction

Stone columns act as vertical drains, and due to their high permeability, allow for the quick dissipation of earthquake induced excess pore water pressure. When water flows through a loose sandy soil, it washes away fine soil particles. The fine sand particles get detached when the hydrodynamic force applied on the soil particles breaks the inter particle bonds between soil grains. These detached soil particles are then migrated by the seepage water. Based on the concentration of the soil particles in the seepage water, these may be captured at the pore constriction of gravels during the flow of water through the stone column. Thus, the clogging of stone column initiates which reduces of the permeability of column. The rate of dissipation of pore water pressure during earthquake is affected due to the clogging of column. In this paper, a mathematical model is proposed to determine the rate of dissipation of pore water pressure of stone column-reinforced ground by considering the clogging effect of column. The result obtained from the proposed model is verified with the available in-situ experimental data. A parametric study is also performed to investigate the effect of different parameters of the proposed model on the clogging of stone column. It is observed that when the permeability ratio, compressibility ratio and area ratio decrease, the possibility of clogging increases. The peak value of the excess pore water pressure ratio can increase up to around 50% due to clogging.     

振冲碎石桩施工质量控制

就振冲碎石桩施工质量中的水、电、石料等三要素的控制提出了建议，指出振冲碎石桩施工的全过程自动控制监测装置对保证施工质量，减少人为因素，实现振冲碎石桩施工的质量控制监测自动化具有重要意义。     

振冲碎石桩在工程中的应用分析

通过对两个工程振冲碎石桩的检测，分析了该工程产生问题的原因，并提出施工中应注意的一些问题，对类似工程施工和检测有一定的借鉴意义。     

振冲碎石桩技术在某电厂冷却塔地基处理中的应用

火力发电厂冷却塔对地基的承载力要求较高,在天然地基承载力或变形不能满足上部结构要求时,一般要采用人工方法对地基进行强化处理。本文通过工程实际,介绍了在火力发电厂冷却塔地基处理工程中振冲碎石桩技术的设计、施工、检测及效果。表明了振冲碎石桩在加固冷却塔地基工程中技术上是可行的,在施工质量和处理效果上可以满足要求,复合地基的承载力和稳定性都得到了较大的提高。     

振冲碎石桩在工程中的应用

根据地质条件，结合工程实例，从加固机理、地基沉降计算、抗震、施工等方面，介绍振冲碎石桩复合地基的应用，说明振冲碎石桩加固地基是可行的，经济的。     

云台山隧道泥砂岩互层段开挖施工技术

指出泥岩、砂岩是隧道施工中常见到的两种岩类，且两种岩石一般以互层现象出现，通过云台山隧道施工实践，分析了此类围岩施工中经常出现的问题，提出并总结了此类围岩开挖时应采取的技术措施。     

Model test of stone columns as liquefaction countermeasure in sandy soils

The shaking table model test was conducted to investigate earthquake resistant behavior of stone columns under the intensity of an earthquake resistance of buildings is VIII. The test results show that when acceleration is less than 0.20 g, composite foundation is not liquefied, settlement is also small and pile dislocation is not observed; when acceleration is 0.3g, ground outside embankment’s slope toe is liquefied and ground within stone column composite foundation is not. It is suggesting that reinforcement scale of stone column foundation should be widened properly. The designed stone column composite foundation meets the requirements for seismic resistance.     

浅谈振冲碎石桩在软土路基处理中的应用

振冲碎石桩加固软土地基的方法在我国各类大小工程中都被普遍应用,本文将以实例介绍振冲碎石桩的计算及设计过程,以及施工中应该注意的问题。