天津滨海新区分层标监测系统技术研究

阐述了天津滨海新区基本地质条件及工程地质特征,分析了对新近系明华镇组以上地层进行全面系统监测的必要性。介绍了滨海新区分层标监测系统建设的工作方法,简述分层标监测系统建设中各种类型分层标的设置及标孔结构设计。在总结前人分层标建设的基础上,结合多年设计施工及监测工作经验,对分层标的标孔结构、标底及孔隙水压力监测孔做了技术研究改进,并与传统的分层标工艺进行了分析比较。工程验证结果表明,各项技术改进应用效果良好,达到预期设计目标。     

北京市地面沉降监测标设计与施工技术

地面沉降监测要求精度最高。本文介绍了北京地面沉降站内,监测配置和基岩标、分层标孔的结构设计,施工特点,以及适用于冲洪积平原的地面沉降监测方法。     

地面沉降监测一孔多用标技术关键与应用实效

在系统总结地面沉降监测设施结构设计、施工工艺及应用成果基础上,设计开发了基岩标兼地下水监测井和分层标兼地下水监测井的一孔多用标技术,并在上海两座地面沉降监测站中得到成功应用.论述了一孔多用标的设计原理、施工技术和应用效果,总结了一孔多用标的技术优势和推广价值,以助于地面沉降监测技术进步与防治工作深化.     

基岩标的施工技术探讨与实践

基岩标是指在覆盖有松散地层的区域内为更准确测定地面沉降量,穿过覆盖层埋设在稳定基岩卜的标杆直通地面,经过保护处理作为相对稳定的基岩水准点。具有标孔要求高、基岩面判层准确、标杆安装要求高等特点。通过浙江省宁波市2座基岩标施工的实践,探讨了确保基岩标质量的关键技术和控制措施,对实际施工有一定的参考作用。     

天津市建成千米基岩标

该标建在市区李七庄南,标深1088m,据我们已掌握的资料,是目前国际上最深的水准基岩标。该标在稳定并投入使用后,可大幅度提高水准测量高程精度,是天津市控制地面沉降工作的基础建设。 该标座落在寒武系灰岩上,岩石质地坚硬。钻孔终孔斜度为零度三十分,设置了三层不同深度和管径的保护管。标杆与保护管均采用石油系列管材。各层     

天津市建成千米基岩标

正 该标建在市区李七庄南,标深1088m,据我们已掌握的资料,是目前国际上最深的水准基岩标。该标在稳定并投入使用后,可大幅度提高水准测量高程精度,是天津市控制地面沉降工作的基础建设。 该标座落在寒武系灰岩上,岩石质地坚硬。钻孔终孔斜度为零度三十分,设置了三层不同深度和管径的保护管。标杆与保护管均采用石油系列管材。各层     

丹江口水利枢纽混凝土坝垂直位移工作基点埋设施工技术

:丹江口混凝土大坝附近下游两岸各建一座大坝垂直位移观测的工作基点。钻孔口径要求不小于 32 5mm。介绍了大口径钻孔取心、防斜和测斜方法。双金属标外保护管 2 73mm ,标心钢管及标心铝管均为 89mm ,介绍了保护管埋设及双金属标安装的施工技术     

放射性分层标监测地面沉降技术设计

本文介绍了放射性分层标监测地层垂直伸缩的基本原理。阐述了放射性弹丸、测井系统、放射性监测系统的技术要求和施工技术要点。介绍了利用放射性分层标监测地层压缩的精度控制方法。     

天津滨海新区抽水引起地面沉降研究

针对天津中新生态城开展的地源热泵工程,采用抽灌水的方式加速地下含水层的流场,提高地源热泵的换热效率,但是抽水会引起地面沉降,本文在中新生态城城市管理中心场地内进行抽水试验,采用新型一孔多标分层标数据采集器监测抽水引起的地面沉降。根据抽水试验首先计算了含水层的渗透系数和抽水的影响范围,根据实测沉降变化规律分析了抽水对地下水位埋深及不同土层的影响,结合同时刻的孔压变化和水位变化规律,证明含水层固结压密是有一定滞后性的。     

增压式真空预压吹填淤泥孔压实时响应及加固机制初探

进行了增压式真空预压处理吹填淤泥的室内模型试验,利用沉降标、微型孔压计和微型十字板剪切仪对试验过程中的土体沉降量、孔压消散以及强度进行监测。结果表明,土体内部注气增压对土体沉降量、孔压累积消散量以及强度提升均有明显促进作用。特别地,获得了增压期间土体孔压的实时响应,并结合数值模拟分析,推断了增压提升淤泥地基处理效果的主要机制为:注气引起增压管/排水板之间土体产生微小的劈裂裂缝,提高了土体的渗透性,并且该裂缝在增压结束后继续提供额外的排水通道,从而在增压后仍能加快孔压消散和土体固结。     

基于正交试验和复合单元法的排水孔优化设计

排水孔是常用的工程渗控措施,其排水降压效果将直接影响工程的安全与稳定,因此,正确模拟排水孔进而优化设计尤为重要。由于影响排水效果的因素众多,优化设计需要针对多种排水孔方案进行渗流分析,计算量较大,采用正交设计法确定排水孔方案可以大大减少渗流分析次数;传统的数值模拟方法在排水孔方案改变时需要重新绘制计算网格,前处理难以实现,采用复合单元法,无需绘制排水孔网格,因而不同排水方案的渗流分析可共用一套网格,降低了前处理的工作量和难度。基于正交试验和复合单元法的排水孔优化设计的具体步骤为：确定试验指标、因素和水平;选择合适的正交表,确定渗流计算方案;对各方案依次采用复合单元法进行渗流分析;根据渗流计算结果进行极差分析和方案优选。该方法能够迅速有效地确定出“最优”的排水孔方案,具有一定的工程实用价值,实例分析表明了该方法的可行性和优越性。     

Black holes in close binary systems and galactic nuclei

After 50 years of observational studies of black holes, great progress has been achieved in this branch of astrophysics. Several dozen stellar-mass black holes have been discovered in X-ray binaries, and several hundred supermassive black holes in galactic nuclei. The remarkable recent discovery of gravitational waves from merging black holes in a binary system by LIGO marks the beginning of a new stage in black-hole research. It is quite possible that gravitational-wave studies will provide definitive evidence for the existence of event horizons in black holes in the near future. On the other hand, the development of methods for space and ground-based radio-interferometry observations provides hope that it will be possible to obtain images of “shadows” of supermassive black holes in galactic nuclei, and to observe directly processes occurring in the vicinities of the event horizons of supermassive black holes. This is important for tests of general relativity in extremely strong gravitational fields.     

冰川表面冰尘洞内病毒研究进展

病毒在驱动生态系统高生物多样性形成以及生态系统营养物和有机物的循环过程中均发挥着重要的作用。冰川洞作为冰冻圈微生物活动的热点, 为病毒提供了特殊的生存环境, 驱使病毒产生了生存与适应机制。通过综述国际上近些年来关于冰川表面冰尘洞内病毒的主要研究成果, 内容涉及冰尘洞在冰川生态系统中的重要性, 冰尘洞内病毒的丰度与生产力, 冰尘洞内病毒的遗传多样性, 病毒与宿主的相互作用关系, 以及病毒对于冰尘洞碳循环和食物网的重要性。此外, 还总结了当前冰尘洞内病毒研究存在的空白： 形态多样性、 降解率、 分离培养、 冰川表面散落冰尘内病毒, 指出了未来研究需要重点关注的几个方面, 为进一步研究病毒对于冰尘洞生态系统的重要影响提供科学参考, 并且对青藏高原冰川表面冰尘洞内病毒未来的研究提出了展望。     

Probabilistic models for ore body recognition

Four statistical models have been developed to aid in exploration drilling for ore deposits. The Austinville (Virginia) deposit, which is a Mississippi Valley-type deposit with 31 million metric tons of ore in 17 ore bodies, provides the data base. Because most ore bodies are not solid ore, holes drilled through them will intersect sub-ore mineralization as well as ore. The statistical models were designed to show whether drilling is through an ore body or not, depending on the mineralization intersected by holes. The models are based on a threefold classification of mineralization penetrated by surface drill holes and were developed for cases of fixed budgets with specified number of drill holes and floating budgets with variable number of drill holes. Two classifications were used: (1) binomial ore/non-ore classification and (2) trinomial ore/mineralized/barren. For the fixed budget model with the ore/non-ore classification, at least five holes need to be drilled to decide whether or not an ore body has been penetrated. For the fixed budget model with the ore/mineralized/barren classification, and for both floating budget models, at least three holes need to be drilled. All decisions are based on a 90% confidence level.     

Proposed algorithm for optimization of directional additional exploratory drill holes and computer coding

Block model estimated based on the drill hole information gathered during exploration stage is not appropriate for short- and medium-term mine planning. Additional information prior to mining is required for various purposes, that the source of this information is drill holes. In most situations, reducing the overall uncertainty on the estimation is the major objective of additional drilling and collecting samples from them. The topic of selecting the optimum location for additional exploratory drill holes has been of interest to mining engineers and geostatisticians in the second half of last century, but all of them are not able to optimize directional drill holes because they are based on the 2D space and do not consider the 3D extension of drill holes and block model. This study introduces a methodology to optimize the dip and location of additional exploratory drill holes based on the defined objective function with considering 3D extension of ore body and drill holes. Direct search simulated annealing used that is efficient and robust method for solving the nonlinear unconstrained global optimization problems. This method is very useful in the case that drilling the drill holes with different dips has been obligated due to topography condition and ore body situation. A case study in gold resource illustrates the method.     

水位骤降条件下有密集排水孔大坝三维渗流场数值模拟研究

对于坝坡布置密集排水孔的工程渗流问题,水位骤降条件下密集排水孔排水效果及坝体和坝基内三维渗流场分布是工程设计人员关心的重要问题。针对坝坡布置排水孔的渗流行为,提出了密集排水孔在水位骤降下渗流状态改变的处理方法。并详细论述了改进的截止负压法求解饱和-非饱和渗流场、排水子结构法和排水孔开关器等精细模拟排水孔的关键技术。工程实例表明,采用该方法可以有效地解决水位骤降下上游坝坡布置密集排水孔三维渗流场的精细数值模拟问题。     

测井曲线在杭东勘查区煤炭普查煤岩层对比中的应用

杭东普查区煤层产状平缓,构造简单,但由于含煤地层为陆相沉积,煤层层数多、厚度、间距变化大,沉积岩相变化快、大范围内缺乏稳定的对比标志层,因此煤岩层对比是本区勘查需要重点解决的难题。通过对比杭东普查区与邻区200余孔的测井资料,分析煤岩层在各种测井曲线的异常特征与异常组合规律,确定了对煤岩层对比有重大意义的标志层,如延长组与上覆延安组的典型视电阻率异常分界;延安组在高视电阻率曲线上的“树杆”状凸起特征;安定组视电阻率曲线近直线的低值形态;4-1煤在视电阻率曲线上呈现出的“斜坡”状或“刀”状高异常,以及在自然伽玛曲线上的“凹坑”特征;侏罗系中统直罗组的高伽马异常,等等。这些典型特征保证了该区煤岩层对比可靠性,为提交优质地质勘查报告发挥了重要作用。     

穿层爆破在南桐矿瓦斯抽放中的应用与数值模拟

穿层抽放是一些高突矿井常用的瓦斯治理手段,在穿层抽放时采用爆破技术已被证明具有良好的抽放效果。以重庆市南桐矿穿层爆破为背景,建立了穿层深孔爆破数学模型;利用数值计算和现场实测抽放数据相结合的方法,分别研究了各爆破孔、控制孔动应力的变化以及爆破应力场强度与抽放效果的关系。研究结果表明,穿层抽放的特点决定了爆破孔与抽放孔的布孔方式。由于炮孔斜穿煤层,煤层各断面动应力场分布极不均匀,药包中心控制孔所受动应力为控制孔中最大。在南桐矿薄煤层试验条件下,药包长度为3.2 m的爆破孔平均破坏半径为0.57 m,较其他两排炮孔大20%以上。炮孔中药包长度是影响瓦斯抽放量的重要因素。爆破孔的平均单孔抽放量较控制孔高55%,爆破钻场较非爆破钻场平均单孔流量大49%。     

有孔管桩单桩承载性状试验及分析

有孔管桩能够有效地加速超静孔隙水压力时空消散,减轻沉桩效应对周围环境的不利影响,但桩身开孔引起的应力集中现象会削弱桩体承载力。为探讨桩身开孔对管桩承载性状的影响,采用室内模型试验方法,在软土地基中开展无孔管桩和3种不同布孔方式的有孔管桩单桩静载荷试验,对竖向荷载下引起桩顶沉降及桩身不同位置的应变进行了监测和分析,获得了各种管桩的Q-s曲线、桩身轴力及桩侧摩阻力的分布规律。对比分析可知,星状开孔有孔管桩的桩身轴力削弱情况最小,双向对穿有孔管桩的桩侧摩阻力最大。     

Early formation of galaxies induced by clusters of black holes

A model for the formation of supermassive black holes at the center of a cluster of primordial black holes is developed. It is assumed that ～10^?3 of the mass of the Universe consists of compact clusters of primordial black holes that arose as a result of phase transitions in the early Universe. These clusters also serve as centers for the condensation of dark matter. The formation of protogalaxies with masses of the order of 2 × 10⁸ M _⊙ at redshift z = 15 containing clusters of black holes is investigated. The nuclei of these protogalaxies contain central black holes with masses ～10⁵ M _⊙, and the protogalaxies themselves resemble dwarf spherical galaxies with their maximum density at their centers. Subsequent merging of these induced protogalaxies with ordinary halos of dark matter leads to the standard picture for the formation of the large-scale structure of the Universe. The merging of the primordial black holes leads to the formation of supermassive black holes in galactic nuclei and produces the observed correlation between the mass of the central black hole and the bulge velocity dispersion.