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1.
通过对三亚华宇度假酒店项目场地运用普通碎石桩地基处理后进行复合地基的静载荷试验和对应的浅层0~3m深度范围内桩间土标准贯入试验建立关系,得到海南三亚地区标贯击数和地基承载力的相关关系散点图及对应表.可以用标贯试验手段检验整个场地的地基承载力,减少了载荷试验的数量,为整个三亚地区沿海的地基承载力的评定提供经验参数,节约检测成本,缩短检测工期.建立了海南三亚地区标贯击数和地基承载力的相关关系,填补了该地区运用标贯试验确定地基土承载力值的空白.  相似文献   

2.
大同--运城高速公路某软基复合地基检测结果分析   总被引:2,自引:2,他引:0  
以山西大运高速公路某段软基处理为例,从挤密碎石桩的加固机理和破坏方式入手,通过对软基复合地基的原位测试结果分析,得出碎石桩不但提高了地基的承载力,增加了桩间土的强度,减少了地基沉降,而且消除或减轻了地基的液化,使复合地基承载力达到了设计要求,特别是为以后在高速公路修筑中的软基处理提供了参考资料.  相似文献   

3.
浅议CFG桩复合地基及其应用   总被引:1,自引:0,他引:1  
笔者运用CFG桩的作用机理,通过CFG桩复合地基处理方法解决了通州区某天然地基标准承载力较低、不满足设计要求、又无其它有效方法解决的地基处理工程问题,阐明CFG桩复合地基为目前城市地基处理工程中地基土饱和、挤密差、天然地基承载力低等特殊情况下较先进、实用、有效的地基处理方法。  相似文献   

4.
地基是工程建设的基础,其承载力计算和预测十分关键,决定着建筑工程上部结构的安全性与稳定性。为实现小数据量、短周期、较高精度的地基承载力预测。本研究提出以地基静载试验数据为依据,利用灰色模型进行计算,结合马尔科夫优化,建立灰色马尔科夫预测模型,预测固定荷载作用下的地基沉降,进而明确相应沉降下的基地承载力。同时,将该模型与传统的灰色GM(1, 1)模型、指数曲线拟合模型进行对比,分析3种模型的优劣。结果表明,案例一中,静载试验下的地基承载能力完好,灰色马尔科夫模型、GM(1, 1)模型、指数曲线模型预测值与实测值的平均相对误差依次为1.55%,3.80%,10.22%,灰色马尔科夫模型精度最高,更契合地基静载试验,能准确有效地明确地基承载力;案例二中,地基在静载试验下发生破坏,破坏前灰色马尔科夫模型预测值与实测值的平均相对误差仅为0.5%,预测效果良好。破坏时,地基沉降迅速增加,加载点模型预测值与实测值的相对误差出现异常,骤增至26.29%,以此可判断破坏前一级加载序列荷载为该地基的极限承载力。运用此模型指导地基静载试验,在保障工程施工安全的前提下,相邻试验点可以适当减少静载试验次数,节约工程施工成本,为信息化地基静载试验提供一个新的计算工具。   相似文献   

5.
文章结合桂林市的几个工程实例 ,对岩土工程勘察中的有关抗剪强度c、φ值的选用 ,地基承载力理论确定方法 ,及地基沉降计算等几个问题进行了粗浅的探讨 ,指出c、φ的确定取决于不同岩土体和不同的试验方法 ,承载力的理论计算值须结合实际情况确定其适应性 ;在正确选取压缩模量和修正标准的基础上确定地基沉降量  相似文献   

6.
根据当地工程地质条件,结合工程结构特点和当地施工技术水平,高层建筑软弱地基采用刚性桩和褥垫层处理,形成复合地基,是一种安全、经济的方法,施工难度小,能充分发挥桩和桩间土的承载力.本文分析了刚性桩桩顶设置粒状材料褥垫层后的桩土变形协调原理,桩和桩间土共同承载荷载的受力机制,复合地基的承载力设计和变形计算方法.提出了复合地基的桩和褥垫层施工质量要求.  相似文献   

7.
本文根据极限分析法的基本原理,研究了粘土地基中矩形截面桩在横向荷载作用下的极限承载力问题,建立了矩形截面桩的极限承载力计算公式。  相似文献   

8.
强夯是处理湿陷性黄土地基的一种有效方法。灵宝市委市政府办公大楼湿陷性黄土地基,经强夯处理后,地基土孔隙比和压缩系数降低,干密度提高,湿陷性被消除,地基承载力大幅度提高并满足了建筑设计基础底面压力220kPa/m2的要求。  相似文献   

9.
水泥粉体深层喷射搅拌桩与干振碎石桩〔1〕、干振灰土桩等一样,也是处理松软地基土的一种有效方法。但与干振碎石桩等其他挤密型复合地基处理方法不同,水泥粉体深层喷射搅拌桩属于摩擦桩型。由于天然地基土对桩体的侧摩擦力和端阻力的共同作用,使复合地基的承载力大幅度提高。然而人们普遍认为,水泥粉体深层喷射搅拌桩法复合地基处理不能解决场地土的液化问题。本文通过工程实例和瑞雷波检测结果,证实了该方法处理的复合地基,除了承载力有较大幅度的提高外,地基土的抗液化能力也可以得到相应的加强。  相似文献   

10.
引碧入连工程,大沙河倒虹吸地质条件复杂,岩性多为淤泥质土和中细砂,前者地基承载力不及80kPa,后者有严重的砂土液化问题,为此采用了复合地基处理,提高了地基强度又防止了砂土液化,在施工中应用了静载荷及动力法进行了检测,肯定了复合地基的有效性。  相似文献   

11.
本文把城市废水、废气、废渣排放量视作有相互联系的灰色系统,建立起城市三废排放量的多序列残差辨识预测模型,并应用于一个实例预测。  相似文献   

12.
Beachrocks like those in Haishan Island's "beachrock field" are rarely found elsewhere. They contain typical cement-aragonite. The assemblages of foraminifera and ostracods show that they are typical littoral sediments, the middle and the lower beds of beachrocks being formed in the desalinized seawater, the upper bed in normal seawater. At least four coastal elevations and subsidences have occurred since Late Holocene. The amplitude of the last three subsidences increased each time and the sea coasts receded. Active elevation has been predominant since 600 years B.P.Periodical coastal elevation and subsidence in Fujian and Guangdong has been occurring for the past several thousand years. Each period was 500 years, 250 years of subsidence, 250 years of elevation.  相似文献   

13.
Observational data obtained during the TOGA-COARE IOP in the "warm pool" area of the West-ern Tropical Pacific were used to analyze some characteristics of the intraseasonal variations in the mixedlayer. The influence of westerly burst and rainfall on SST, salinity. and mixed layer depth are discussed.There are two pairs of counteracting processes in the "warm pool" mixed layer: (1) The increase of mixedlayer depth caused by local westerly bursts and the decrease of mixed layer depth caused by larger scaleeasterly relaxation;(2) the vertical mixing by local wind and the strong stratification due to rainfall in themixed layer. Some possible mechanisms through the interactions between the intraseasonal time scale varia-tions of the oceanic mixed layer and atmospheric low frequency oscillations are revealed.  相似文献   

14.
It is well known that there are two patterns of potash deposition in lacustrine fades: " tear drop pattern " (the Dabsan saline lake is a typical example)and " bull's eye pattern " . Potash-forming in tear drop pattern is still continuing.The 2,678 m A . S. L . lake in the middle of the Qarhan playa in the Qaidam Basin covers an area of 210 km2 , and has an average depth of 0.39 m. Its MgCh type surface brine is 280-340 g/1 in salinity and mainly consists of Na, K, Mg and Cl. As a rule, the potash deposits occur as evaporite distributed in tear drop pattern at the northern and northeastern lakeshore zones. They mostly consist of carnallite and halite, occasionally sylvite.The deposition is very unstable and controlled principally by the varying supply of deposit materials from the Golmud River in the south.The potash deposits were formed when concentration of the surface brine reached a certain degree in the main evaporating season. Their forming process followed some crystalization paths in the phase d  相似文献   

15.
1IN T R O D U C T IO NDue to acceleratingurban sprawl and suburbanizatio,nlargeareaoffarmlandwere changed intonon-agricultur-allanduse sincethelate1990s,especiallyinSouth Chi-na.Meanwhile some villageswere surrounded by urbanbuilt-upareasand became"thevillagesin urban area",which arenamed hereas"urban villages."Specificallyindefinitio,nurban villageisa ruralcom munity inurbanbuilt-upareasbecause of drasticurban sprawl,subur-banizationand industriadlispersion.A nd inrealityur-ban villagee…  相似文献   

16.
文章记述了"7.20"资源县瓜里乡山洪泥石流爆发情况及重大损失,总结其爆发特点,分析其原因,由此建议对广西全区进行一次专门调查.  相似文献   

17.
INTRODUCTIONColloids (orsub micrometerparticles)areoperationallydefinedasparticlesbetween 1nmand1 μm (Vold ,R .D .andVold ,M .J.,1 983) .Thedistributionbetween“dissolved”and“particu late”phaseinaquaticchemistryusedtobedefinedbyafiltrationwith 0 .45 μmporesizefilters.Th…  相似文献   

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所长"道歉"     
"老杨,我是来向你道歉的,同时就你反映的宅基地问题给你一个明确的答复……"在家正忙活的修武县周庄乡杨楼村村民杨某,听到薛所长的话后愣住了,这到底是怎么回事?  相似文献   

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