论"单位涌水量就是导水系数"

单位涌水量是井抽水水位降深换算为1 m时的单井出水量;导水系数是含水层宽度为1 m时,地下水水力坡度为1时的单宽流量.二者之间从定义上看毫无关系,但它们的单位(m3/d·m)(m2/d)是相同的.笔者经过多年探讨和初步试验后发现,单位涌水量就是管井抽水所利用含水层的导水系数.     

孵漂石地层大口径钻头与钻进工艺的选择

根据工程实例，通过钻头和钻进工艺的对比试验，得出了利用大直径滚刀钻头，在致密卵漂石地层施工中大口径桩孔，能大幅度提高钻进效率。     

热液体系氢、氧同位素分馏机制及其地质意义

探讨了热液体系氢、氧同位素地球化学行为及其与水/岩交换同位素分馏的内在关系。有效W/R值是除温度条件外,另一控制蚀变岩石和热液水氢、氧同位素组成变化的因素。此外还根据数个矿区成矿热液水和蚀变岩石氢、氧同位素组成及变化特征对水/岩交换和W/R值的应用及地质意义展开讨论。最后提出热液体系中大气降水和岩浆热液水氢、氧同位素组成演化模式简图。     

Pore fluid pressure effects in anisotropic rocks: Mechanisms of induced seismicity and weak faults

Many observations and studies indicate that pore fluid pressure in the crustal rocks plays an important role in deformation, faulting, and earthquake processes. Conventional models of pore pressure effects often assume isotropic porous rocks and yield the nondeviatoric pressure effects which seem insufficient to explain diverse phenomena related to pore pressure variation, such as fluid-extraction induced seismicity and crustal weak faults. We derive the anisotropic effective stress law especially for transversely-isotropic and orthotropic rocks, and propose that the deviatoric effects of pore fluid pressure in anisotropic rocks not only affect rock effective strength but also cause variation of shear stresses. Such shear stress variations induced by either pore pressure buildup or pore pressure decline may lead to faulting instability and trigger earthquakes, and provide mechanisms for the failure of crustal weak faults with low level of shear stresses. We believe that the deviatoric effects of pore fluid pressure in anisotropic rocks are of wide application in studies of earthquake precursors and aftershocks, oil and gas reservoir characterization, enhanced oil recovery, and hydraulic fracturing.     

采用小径密抗桩一条龙抢治滑坡的方法及效果

以往整治滑坡,较多地使用大口径挖孔桩或钻孔灌注抗滑桩,周期长、成本高。川地208队在治理重庆制药五厂已处于危急态势的滑坡中,采用“天平式”控制、勘治结合、快速抢险,用三排小径密抗桩(300mm口径)整治,取得明显成效。实践表明:浅层滑坡采用较小口径的密抗桩,并辅以排水,能达到事半功倍的效果。     

Angular resolution of terrestrial laser scanners

Knowledge of a laser scanner's spatial resolution is necessary in order to prevent aliasing and estimate the level of detail that can be resolved from a scanned point cloud. Spatial resolution can be decoupled into range and angular components. The latter is the focus of this paper and is governed primarily by sampling interval and laser beamwidth. However, emphasis is often placed on one of these—typically sampling interval—as an indicator of resolution. Since both affect the resolution of a scanned point cloud, consideration of only one factor independent of the other can lead to a misunderstanding of a system's capabilities. This will be demonstrated to be inappropriate except under very specific conditions. A new, more appropriate resolution measure for laser scanners, the effective instantaneous field of view (EIFOV), is proposed. It is derived by modelling the shift variance of the equal angular increment sampling process, laser beamwidth-induced positional uncertainty and observed angle quantisation with ensemble average modulation transfer functions (AMTFs). Several commercially available terrestrial laser scanner systems are modelled and analysed in terms of their angular resolution capabilities using the EIFOV.     

大直径硬岩环状取芯钻具的试验研究

在分析了国内外大直径基岩孔钻进取芯方法的基础上,提出了一套低能耗、高效率、低造价的大直径硬岩环状取芯钻具,设计制作了样机,并进行了样机试验.试验结果表明:该设计方案、工艺可行,达到了预期设计目标,为大直径硬岩取芯施工提供了一种新的机具.     

洪涝统计方法探讨

利用深圳气象台1953--2005年的雨量资料，对洪涝的两种统计方法进行了对比分析，并引出了更为科学和合理的“任意连续10d／20d雨量统计洪涝的方法”。通过检验，该方法能够较准确地反映洪涝灾害的实际情况。     

桩土相互作用时桩参数对大直径空心桩承载影响的有限元研究

运用Ansys有限元技术,分析了在竖向荷载作用下大直径空心桩桩顶沉降、桩端沉降与桩身压缩三者的关系,桩长L对桩身轴力的影响,桩长L、桩径D、桩体弹性模量E对桩P-s曲线的影响,桩长L、桩径D对桩P-Se（桩端沉降与桩顶沉降的比值）曲线的影响,具有工程上的实际意义。     

Comparison of the spatial distribution of ground motion between main shocks and strong aftershocks

Using the ground motion attenuation relation, we calculated and compared the effective peak acceleration (EPA) generated by main shocks and their strong aftershocks of 21 earthquake sequences with MS≥7 occurred in Chinese mainland and offing of China during 1966~2002. The result shows that EPA of strong aftershocks usually exceed that of main shock for 76.2% earthquake sequences and EPA of more than 50% strong aftershocks are greatly lar-ger than that of main shocks in large area, which suggests that it is necessary to take damage produced by strong aftershock into account in the probabilistic seismic hazard analysis and the seismic design.