On long-wave breaking I. Consideringnth power bottom friction     

Tian Ji-wei  Lou Shun-li  Hu Dun-xin  Li Hong-yan  Zhang Fa-gao 《中国海洋湖沼学报》1995,13(2):110-118

Longwave breaking is the agent for many important upper ocean layer processes including the transfer of horizontal momentum. In a previous study on the process of longwave breaking, only linear bottom friction was considered. In this paper, we discuss the longwave breaking phenomena in the more general case ofnth power bottom friction. Using the theory of blowup of solution, the criterion for the time and location of the longwave breaking can be obtained. Contribution No. 2559 from the Institute of Oceanology, Chinese Academy of Sciences. This project was supported by NSFC (No. 49376254).  相似文献   

干振碎石桩复合地基处理及其效果     

程礼来  武开文  孟凡奇  牛二元  程礼来 《河南国土资源》1996,(3)

干振碎石桩是处理松软地基土的一种行之有效的方法，它是挤密桩的一种。新乡市地方铁路处仓库场地经干振碎石桩地基处理后，桩间土密实度有明显的提高，液化指数大幅度降低，复合地基承载力相应提高，满足了设计要求。  相似文献   

管棚支护及注浆技术在-380石门过刘桥断层中的应用     

黄大兴  王健 《中国煤炭地质》2008,20(1):41-43

刘桥断层位于刘桥一矿东北侧,落差110～210m,通过钻探揭露、物探探查、流量测井技术,对刘桥断层破碎带的富、导水性进行了研究,在-380石门巷道过刘桥断层前进行了管棚支护及预注浆加固工程,以及在巷道过刘桥断层过程中,采取了一系列行之有效的掘进支护措施,确保了-380石门巷道安全通过刘桥断层。  相似文献   

运用水平定向钻进技术实施管道更换的新方法     

李淑海 《上海国土资源》2008,(1):49-52

结合工程实例,介绍了运用非开挖水平定向钻进技术实施原有管道更换的新技术,对旧有管道的更换探索一条经济可行的便捷之路,具有借鉴意义。  相似文献   

地基处理技术规范中关于沉降计算公式的使用条件分析     

巫虹  富锡良 《上海国土资源》2008,(1):44-48

刚性桩复合地基沉降计算应按现行国家标准,可采用分层总和法进行沉降计算。该沉降计算方法是目前绝大多数工程采用的方法。但该法在理论上还需要进一步完善,结合工程实例,详细分析地基处理规范中沉降计算公式的适用条件,对以后工程实践过程中有针对性地收集工程数据,指导规范修改有一定积极意义。  相似文献   

Constraints on crustal and mantle structure of the oceanic plate south of Iceland from ocean bottom recorded Rayleigh waves     

Frederik J. Tilmann  Torsten Dahm 《Tectonophysics》2008,447(1-4):66

From April to July 2002 we carried out a deployment of 6 ocean bottom seismometers and 4 ocean bottom hydrophones in the North Atlantic south of Iceland. During the deployment period we recorded clear Rayleigh waves from 2 regional and 14 teleseismic earthquakes. This corresponds to a Rayleigh wave detection rate of nearly 92% for events with M_W ≥ 6.06.0 and epicentral distance less than 110°, close to detection rate estimates based on noise level variability. We measured Rayleigh wave event-station group dispersion and inter-station phase dispersion for one Mid-Atlantic Ridge event. The group dispersion curve is sensitive to the structure of the North-East Atlantic with an average age of  39 Myr. The phase dispersion curve is sensitive to the structure just south of Iceland (average plate age 33 Myr). Both dispersion curves indicate faster velocities than previously postulated for oceanic plate generated at the Reykjanes Ridge. A grid search approach was used to constrain the range of models fitting the data. The high velocity seismic lid just south of Iceland in the model for the phase dispersion path is slower or thinner than in the group dispersion model, which averages over a larger area and a somewhat older plate age, but the velocities in the low velocity half space are similar. We further consider the residual bathymetry in the experimental area. The residual anomaly decreases by 300–400 m from the Reykjanes Ridge to the  30 Myr old plate south of Iceland. This decrease can be explained by the disappearance of a mantle thermal anomaly associated with the Iceland plume. Both the residual bathymetry and the surface wave data are thus consistent with the notion that the southward spreading of the Icelandic plume is channelised underneath the Reykjanes Ridge and does not spread far outside this channel.Based on the experience from the pilot experiment, we estimate that a minimum recording time of 13–15 months in favourable weather conditions (April–September) is required to record enough data to map the spreading plume with surface waves, and to produce a tomographic image to a depth of 1000 km using body waves. This can be achieved by a continuous deployment of at least  20 months, or by two or three deployments during the spring and summer of consecutive years.  相似文献   

咬合桩在含承压水地层施工中的应用     

张治纯  程淼德  何建明  邓承沂 《探矿工程》2008,35(9):45-47

通过南京地铁一号线南延线TA08标段胜太路车站咬合桩施工,介绍了咬合桩施工的基本工艺流程。同时为减少承压水对成孔和灌注混凝土的不利影响,采取了用提水斗和潜水泵降水等措施,保证了工程的施工质量。  相似文献   

地表不具备钻探条件下的盾构机通过空洞地段施工技术          下载免费PDF全文

晏胜荣  贺飞 《探矿工程》2008,35(9):76-79

本区间因隧道下穿南航酒店和火车站地中海商场及停车场,大部分区域无法实施钻探。而由周边地质资料及施工所反映的情况推测,该区域有存在空洞的可能。未探明的空洞可能对盾构机掘进造成不利影响,如盾构机栽头、地层塌陷等。因此,在盾构机通过未探明区域前必须进行探测和预处理,以指导盾构机掘进。  相似文献   

空气定向水平井钻进注气量试验研究     

向军文  刘强  隆东 《探矿工程》2008,35(11):7-9

通过对空气正循环水平井的注气量进行实验研究,得出实际注气量应是满足关键点处最小动能时,将井底理论计算压力扩大17倍以后所对应的注气量,这对实际钻井前的设计有很好的指导作用。  相似文献   

宝泉抽水蓄能电站引水系统上斜井古风化壳地层灌浆处理          下载免费PDF全文

崔雪玉  赵涵滢  潘涛  李明 《探矿工程》2008,35(12):28-34

宝泉抽水蓄能电站引水系统上斜井开挖揭示,在高程668000～651000 m和高程526000～514000 m处,分别穿过古风化壳地层。古风化壳地层岩石极为破碎,夹泥较多,基岩裂隙发育,地下水丰富,透水率较大。古风化壳地层段地层的灌浆处理,成为斜井开挖能否顺利通过该地层的关键,并且直接影响着电站的安全、稳定运行。针对上述问题,通过采取阻水帷幕、高压固结、锥形帷幕灌浆几种方法联合处理,取得了满意的效果。详细介绍了具体的灌浆处理技术措施,分析了处理效果。  相似文献