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1.
颜万才 《江苏地质》1997,21(3):177-182
砖砌护筒是一项简便实用的施工技术。通过砖护筒在无锡市新吴桥桥桩京杭大运河浅水域,软弱复杂地层中的应用实例,介绍其适用条件,设计,施工要点以及效果验证等。  相似文献   

2.
何开兆 《广西地质》2002,15(4):51-54
文章通过深能钦州码头油库工程海上码头引桥桩施工的工程实例,阐述钢护筒护壁人工挖孔在海上基桩施工的基本工序及施工工艺,证实钢扩筒护壁人工挖孔施工工艺,在地层简单的浅海场地,是一种行之有效且元污染、机具简单、成本低、进度快的施工方法。  相似文献   

3.
万维方 《探矿工程》2003,30(5):9-11
以江汉五桥主桥施工为例,介绍了桥梁深水基础施工方案的选定及施工要点,重点对砂层长钻孔桩施工、钢护筒渡汛及钢套箱围堰施工进行了分析。  相似文献   

4.
本文以浙江省椒江大桥A标8#-28#墩水上钻孔灌注江桩的钢护筒加工为例,介绍了一般大直径超长钢护筒的振埋理施工技术.  相似文献   

5.
石飞轮 《探矿工程》2006,33(2):50-51
江苏苏通大桥桥基场地地质条件较差,在钻孔桩施工中出现护筒下沉不到岩层的情况;采用超标聚丙烯酰胺泥浆使工程得以顺利进行。介绍了超标PHP泥浆的特点、制作工艺及使用情况等。  相似文献   

6.
水上钻孔灌注桩施工工艺   总被引:3,自引:0,他引:3  
皮跃进 《福建地质》2001,20(1):53-56
水上钻孔灌注桩施工应根据水底地质地貌情况,解决好护筒的选型、止漏、埋设、吊拔以及水中桩身的保护。  相似文献   

7.
唐俊 《探矿工程》2007,34(1):18-20
三门江大桥水中主墩系高桩承台,采用钢吊箱围堰法施工,利用简易的型钢拉压柱作为吊箱的吊挂结构,将吊箱吊挂在钻孔桩钢护筒上,施工操作简便,降低工程成本,是一项值得推广和应用的施工技术。  相似文献   

8.
施工φ3 ̄4.4m空心桩,需要预制空心桩节和护筒,搭建水上平台,进而介绍了钻孔施工,桩节组拼以及压浆等工艺。与实心桩相比,空心桩显示了独特的优越性。  相似文献   

9.
青岛女姑山跨海桥墩基础,采用大口径海上钻孔灌注桩施工,结合工程实践,分析了海潮对地压的影响与钢护筒埋设最佳值;探讨了海上施工泥浆循环系统的合理布设;海水泥浆的配制维护及钻孔护壁等问题。  相似文献   

10.
唐爱平 《湖南地质》2002,21(2):127-129
钻孔灌注桩的质量,取决于对施工各个环节的质量预控,永州市政府大楼桩基和其它一些工程施工中,在测量放线、护筒埋设、钻机对位、钢筋笼下设和孔底沉渣、孔内泥浆及混凝土浇筑等环节节采取了一系列严格的质量预控措施,从而保证桩体到了设计要求。  相似文献   

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Chronological analyses of correlations between certain global repeating events (mass extinctions of marine organisms, meteorite impacts, and flashes in the frequency of geomagnetic reversals) during the Phanerozoic Eon and the motion of the solar system in the Galaxy are presented for five rotationally symmetrical models for the regular Galactic gravitational field. Thirteen of sixteen mass-extinction events can be described by a repetition interval of 183±3 million years. This is in agreement with the anomalistic period (interval between two subsequent passages of the Sun through the apocenter of its Galactic orbit) in the model of Allen and Martos. The positions of the minima and maxima in Gaussian functions approximating the frequency distribution for geomagnetic reversals also agree with the times of passage of the Sun through the apocenter and pericenter, respectively, of its Galactic orbit in this model. The maximum in the distribution of the deviations of the dates of mass extinctions from the nearest dates of impacts of large, crater-forming bodies is close to zero, providing evidence that many such events are correlated. As a rule, extinctions follow impact events. The impacts of large bodies have occurred most often when the solar system passes through the Galactic plane, while mass extinctions occur more often at some distance from the Galactic plane (about 40 pc). As a rule, intervals of increases in the frequency of geomagnetic reversals coincide with dates of impacts of large bodies. At the same time, these intervals do not show a clear correlation with the dates of mass extinctions. The intensity of mass extinctions, like the energy released by impacts, is consistently higher in periods when the Sun is moving from the apocenter toward the pericenter of its orbit, than when it is moving from the pericenter toward the apocenter. Thus, there is evidence for a variety of relationships between repeating global events in the Phanerozoic and the motion of the Sun in the Galaxy. Long-period variations in the frequency of geomagnetic reversals are correlated with the orbital motion of the Sun, and increases in the frequency of geomagnetic reversals are correlated with impacts. Mass extinctions are correlated with the impacts of large bodies, whose motions may have been perturbed by clouds of interstellar material concentrated toward the Galactic plane and by the shock front associated with the Perseus spiral arm, through which the solar system passes. The velocity of the Sun relative to the spiral pattern is estimated.  相似文献   

13.
韩明超  李鸿娟 《地下水》2012,34(5):12-13
在计算山前侧向补给量的方法中,最常用的就是达西断面法,但达西断面法需要获取较多的参数,对于山前无钻孔或只有少量钻孔且水文地质研究程度较低的区域,很难采用达西断面法来计算得到山前侧向补给量。对于无法运用达西断面法但存在完整式截潜工程的山丘区,可以结合完整式截潜工程的截潜量利用水量均衡法计算山前侧向补给量。  相似文献   

14.
通过2004年度各相关图幅的大力工作,在基础地质、矿产和资源等方面取得了大量实际材料,综合研究区域构造.地层格架、青藏高原地质图和青藏高原南部火山岩及其地球动力学意义等,取得重要进展和新认识,在矿产资源、旅游和人文景观等方面也取得重要阶段性成果。  相似文献   

15.
通过2 0 0 4年度各相关图幅的大力工作,在基础地质、矿产和资源等方面取得了大量实际材料,综合研究区域构造地层格架、青藏高原地质图和青藏高原南部火山岩及其地球动力学意义等,取得重要进展和新认识,在矿产资源、旅游和人文景观等方面也取得重要阶段性成果。  相似文献   

16.
关中盆地大荔地区地下水氟水文地球化学规律   总被引:2,自引:0,他引:2       下载免费PDF全文
为了研究关中盆地大荔地区氟的水文地球化学规律,采集239个地下水样品及35个土壤样品,分析了水化学类型和水化学组分对氟的影响,结果表明在弱碱性环境下,重碳酸钠型是促进氟富集并增强围岩向地下水中转化的主要因素;硫酸钙镁型的地下水抑制氟富集。水化学组分中Na+、Cl-、HCO3-、pH与氟呈正相关,而Ca2+则抑制水溶液中氟含量增加;迁移系数与HCO3-、pH呈正相关关系,与其他主要离子呈负相关关系。利用Preeqic软件分析了饱和指数和Ca2+、F-的离子活度,得出萤石的平衡控制着氟和钙的水文地球化学行为,F-可能来源于萤石和方解石的分解。  相似文献   

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Doklady Earth Sciences - A new approach to the problem of determining the density of emission fluxes of anthropogenic impurities from distributed urban sources by the rate of growth of the integral...  相似文献   

19.
The significant role of the drainage area’s geological background in the formation of the groundwater runoff in the active water-exchange zone was revealed for the first time on the basis of long-term observations of streams of the Upper Kolyma River region during the autumn-winter low-water period, when the rivers are fed only by the groundwater recharge. The analysis of all the available data made it possible to define the characteristic periods in the autumn-winter low-water season. The waters of the seasonally thawed layer play the dominant role in the river’s recharge in September; the suprapermafrost water, in January; and the subgelisol water (nonfreezing water streams) during the 30-day-long period of the minimal flow. The quantitative parameters of the groundwater runoff corresponding to its module during this period reflect the water influx to the active water-exchange zone. It is established that the latter is minimal in the In’yali-Debin synclinorium, which consists of sedimentary rocks formed in deepwater trough environments. Their subsequent transformation proceeded under the action of subduction-accretionary and shear strains. The water availability in the active water-exchange in the Ayan-Yuryakh anticlinorium zone is substantially higher, although the Late Paleozoic and Early Mesozoic sedimentary formations of this area were also deposited in deepwater trough settings, but their subsequent evolution was related to the uplift of the anticlinorium. The maximal watering is observed in the active water-exchange zone of the Omulevka terrane, which is composed of Paleozoic terrigenous-carbonate and carbonate formations. The differences in the hydrogeological regimes of the terranes may be significant with respect to their geoecology.  相似文献   

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