厦门翔安海底隧道施工关键技术研究

厦门翔安海底隧道是我国第一条海底隧道,陆域浅埋暗挖地段,其地质条件差,多为全、强风化花岗岩,且地下水丰富。前期施工过程中支护结构常发生较大的变形,为了保证施工安全和进度,通过现场试验,得出一套合理的控制变形措施,使隧道拱顶下沉、水平收敛得到较好控制。在海底硬岩地段进行了钻爆试验,得出较好的爆破方案和参数,并采用声波仪和位移计对围岩损伤范围进行了检测。     

近间距隧道爆破地震效应的试验研究

为了解决层状岩体中采用钻爆法修建近距离双线隧道的爆破影响问题,基于现场试验,总结了爆破衰减规律.试验结果表明,新建隧道爆破时,振动速度随着与爆源距离的增大成非线性减小;振动速度具有很强的方向效应,迎爆面径向振动速度均大于切向振动,径向振动速度对既有隧道和新建隧道围岩的损伤起主导作用;采用上下台阶开挖时,上台阶爆破冲击波对既有隧道的影响比下台阶显著.根据萨道夫斯基回归公式给出了距爆源不同距离的单段最大装药量.将爆破对新建隧道本身围岩的损伤破坏和对相邻隧道的影响结合起来综合考虑,对层状岩体中隧道爆破参数进行了优化.     

隧道围岩特性参数反分析与数值模拟

为确定合理的隧道围岩应力场和参数,采用位移反分析法进行分析.结合现场监测数据和FLAC3D有限元软件进行反演分析和围岩变形数值模拟.研究结果表明:运用FLAC3D仿真模拟开挖,隧道拱顶是危险点,开挖之后拱顶上部围岩下沉值较大;通过现场实际监测拱顶点的位移分析可知,当从第六天之后围岩趋于稳定下沉值22 mm,回归分析确定了拱顶下沉值随时间的变化指数曲线关系;根据位移反分析确定围岩弹性模量为2.5 GPa适合该工程条件,围岩其他参数也可按照该方法进行确定.     

粘弹性动态增量反演分析在隧道施工中的应用

对深圳莲盐高速公路隧道围岩中的凝灰熔岩进行了流变试验,得到了围岩的流变模型;结合隧道的施工过程,根据围岩的收敛变形和拱顶下沉,采用改进的自适应遗传算法对粘弹性位移进行优化反分析,并利用反演得到的围岩参数,如弹性模量、粘滞系数等对变形进行预测.研究表明,利用试验得到的围岩流变模型,结合隧道施工过程的动态增量反演分析,可以较好地模拟围岩的实际性态,对指导施工具有重要意义.     

四面山砂泥互层隧道爆破参数优化研究

在近水平软硬互层围岩隧道钻爆开挖的过程中,由于水平方向层理、节理、弱面以及软弱夹层的存在,使得光面爆破的轮廓平整度很难得到保证,并导致较为严重的超欠挖现象。以四面山层状围岩隧道为工程依托,基于X射线衍射试验以及室内物理力学试验所获取的砂、泥岩的力学参数,综合考虑微差、孔间距、不耦合系数等因素,采用正交试验制定了砂泥互层围岩隧道爆破模拟方案,并对重庆江习四面山近水平砂泥互层围岩隧道进行了爆破优化数值模拟,得到了层状围岩隧道爆破优化方案,将原爆破方案及优化方案与现场测试结果进行了对比,结果表明模拟结果与现场测试值基本符合．研究成果可在类似隧道爆破施工中推广应用。     

鹤顶山隧道钻爆设计与施工技术

根据公路隧道“新奥法”施工原理，提出了光面爆破的施工程序，给出合理的钻爆设计参数，控制超欠挖并确保围岩稳定，降低工程成本。     

四面山砂泥互层隧道爆破设计参数优化

在近水平软硬互层围岩隧道钻爆开挖的过程中,由于水平方向层理、节理、弱面以及软弱夹层的存在,使得光面爆破的轮廓平整度很难得到保证;并导致较为严重的超欠挖现象。以四面山层状围岩隧道为工程依托,基于X射线衍射试验以及室内物理力学试验所获取的砂、泥岩的力学参数,综合考虑微差、孔间距、不耦合系数等因素,采用正交试验制定了砂泥互层围岩隧道爆破模拟方案;并对重庆江习四面山近水平砂泥互层围岩隧道进行了爆破优化数值模拟,得到了层状围岩隧道爆破优化方案。将原爆破方案及优化方案与现场测试结果进行了对比,结果表明模拟结果与现场测试值基本符合。研究成果可在类似隧道爆破施工中推广应用。     

浅埋软弱岩层隧道的钻爆设计与施工

在隧道软弱浅埋围岩地层的钻爆设计及施工中,以减小爆破产生的振动效应,减轻对围岩的扰动出发,论述了软弱围岩的爆破设计方法与爆破参数的选定以及实施效果分析。     

层状岩体中近邻双线隧道爆破的振动响应研究

近邻双线隧道爆破开挖时，为了避免新建隧道爆破施工产生的地震波危夏既有隧道的安全和稳定。基于数值模拟和现场试验，分析了层状岩体中采用钻爆法修建近距离双绒隧道的爆破振动响应．结果分析表明，对于既有隧道，迎爆面侧墙处的振动速度和反射拉应力最大，而且振动速度具有很强的方向效应，隧道径向振动速度大于切向振动速度，其规律与现场爆破试验结果有较好的一致性．将爆破对新建隧道本身围岩的振动损伤度和对相邻隧道的振动影响结合起来综合考虑，提出了层状岩体隧道爆破施工中减轻振动的几种措施。并对隧道爆破参数进行了优化．图7，表4，参8．     

监控量测在高速公路隧道施工中的应用

介绍了茶林顶隧道施工监控量测周边位移及拱顶下沉断面的布置方案,举例分析了典型断面的周边位移及拱顶下沉量测数据,得出了类似围岩条件下隧道施工引起围岩变形的二元回归公式,对茶林顶隧道的后期施工有很大的指导意义。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the