层状岩石倾角对弹性模量的影响研究

层理倾角对互层复合岩体的力学特性和物理参数等具有显著的影响,为研究层状岩石倾角对互层复合岩体弹性模量的影响,首先推导出水平状互层复合岩体平行于层理方向和垂直于层理方向的弹性模量,进而推导了层理倾角与互层复合岩体弹性模量关系的解析解,并通过不同层理倾角页岩的单轴抗压实验验证了解析解的正确性。     

围岩性质对最大主应力赋存状态的影响

通过对北京科技大学近几年在我国四个金属矿山实测结果的分析，对最大地应力的分布规律进行了探讨，指出最大地应力的大小与测点深度和围岩性质均呈现良好的线性关系。     

冲击荷载对具有轴向静应力红砂岩应力波传播速度的影响特性

岩体工程爆破开挖时，距爆源不同距离处的围岩体承受不同大小的冲击荷载和地应力。为研究冲击荷载和地应力对岩石应力波传播速度的影响，利用改进SHPB试验装置对红砂岩进行应力波传播试验，设置7个等级的轴向静应力和冲击速度，分别模拟工程中的地应力和冲击荷载大小。基于试验得到入射波和透射波起跳点的时间差，计算岩石的应力波传播速度，得到静应力和冲击速度对应力波传播速度的影响规律。构建岩石应力波传播速度与冲击速度的关系经验模型，探索拟合参数随轴向静应力的变化规律。通过测量冲击试验后岩石的声波波速，得到受载后岩石声波波速随冲击速度的变化规律，探究动载荷对岩石应力波传播速度的影响机理。研究结果表明，具有轴向静应力岩石的应力波传播速度随冲击速度的增加先增大后减小，二者呈高斯函数的变化关系。轴向静应力显著影响应力波传播速度与冲击速度的变化关系，各个拟合参数随着轴向静应力的增大呈现不同的变化趋势。在不同的轴向静应力工况下，受载后岩石的声波波速随着冲击速度的增大呈现“平缓减小—急剧减小”的变化趋势。研究结果有助于分析深部工程岩体爆破开挖应力波的传播规律以及邻近结构的稳定性分析。      

数值方法中岩体力学参数的选择

对岩体工程数值计算方法中节理岩体力学模型（包括变形特性、强度特性）的选取进行了分析总结。结果表明，节理岩体的强度模型与变形掀起性都与岩体中的岩块材料性质、岩体中结构面性质及其分布形成以及所处的地应力环境有关，提供了不同条件下的岩体力学模型的数学表达式，为数值计算中节理岩体力学模型的选取提供参考。     

金川二矿区1138m分段机采盘区分段道变形监测及稳定性研究

针对二矿区采准工程埋藏深、地压大、工程地质条件恶劣、巷道返修成本高等特点，通过对1138m分段道与分层联络道的变形监测，结合现场巷道破坏、工程地质条件、地应力环境、支护特征、采动影响等的调查研究，综合分析采准巷道失稳的主要原因为巷道所在的多种岩浆岩频繁穿插的大理岩组（Ⅲ3岩组）的岩体结构特点即蚀变带、挤压破碎带发育起支配作用。并据此提出二次支护与巷道破坏后的重新支护直强不宜弱的论点与地压控制措施，为后续采矿的顺利进行提供科学依据。     

西周岭隧道地应力测量及岩爆预测分析

为指导施工,提高施工的安全性和经济性,对西周岭隧道进行了钻孔水压致裂法地应力测量.测试结果表明:西周岭隧道深埋段地应力场以水平应力为主,在测试深度内最大水平主应力值为10.57～19.39MPa,具中等偏高应力水平;最大水平主应力方向为近N33°W,与隧道走向的夹角较小,即地应力对隧道围岩稳定性较为有利.基于地应力实测结果,本文采用Hoek判据、Turchaninov判据、Russenes判据和工程岩体分级标准等4种判别方法进行岩爆预测,并分析了发生岩爆的临界深度,认为西周岭隧道深埋段有发生轻微-中等岩爆的可能,发生岩爆的临界埋深厚度约为397m.因此,在施工过程中应采取合理的开挖方式及防岩爆安全措施,防止岩爆灾害的发生.     

山东金青顶矿区深部矿体开采诱发微震活动分析

随着金青顶矿区开采深度的增加,地应力值逐渐增大,造成巷道围岩破坏越来越严重,且具有一定的岩爆倾向性。为进一步探究金青顶矿区深部开采诱发岩体破裂失稳规律,在金青顶矿区深部建立矿山微震监测系统,连续实时采集井下微震活动信息,对-825 m中段Ⅴ号矿体11#试验采场开采活动进行连续监测,重点分析开采扰动下岩体破裂前累计视体积、能量指数和施密特数等微震参数的变化特征,得出当前矿体整体损伤程度较小,岩体破裂主要是由岩体开挖以及爆破振动引起。     

遥感及综合物探方法用于山东招远南部隐伏成矿侵入体的空间定位

胶东是我国最重要且规模最大的金矿集中区,近年研究表明金矿与克拉通破坏密切相关。胶西北地区的成矿成岩年龄初步显示金成矿地质体为郭家岭岩体。招远南部的大尹格庄和夏甸金矿的成矿年龄表明了金矿床与郭家岭岩体的直接关系,但该区并未发现郭家岭岩体的出露。通过遥感解译获得了区域线性和环形构造,圈定出隐伏岩体赋存的可能位置,并利用航空磁法、Eh-4连续电阻率成像系统和CG-5相对重力仪进行了综合勘探。测量结果显示,研究区郭家岭岩体磁异常不明显,以中高等电阻率(1 000~3 000Ω·m)、低相对重力异常(8 mGal)的隐伏岩枝状侵入,埋藏深度约为1 km。与成矿相关的蚀变破碎带表现为低电阻率(0~1 000Ω·m)的电性体,与其他地质体区分较明显。多种地球物理勘查方法的联合运用,对定位隐伏侵入体和识别蚀变破碎带具有很好的效果。     

应用凯塞效应测定五龙金矿的地应力

应用岩石的凯塞效应现象，可以测出岩体内赋存的地应力。该种方法简单、快捷、经济、有广阔的发展和应用前景。     

鲁西铜石地区金成矿预测靶区矿体埋藏深度估算及其意义

鲁西铜石地区位于沂沭断裂带西侧的鲁西隆起区,是20世纪末新发现的金矿聚集区,燕山期侵入的铜石杂岩体控制了金矿床的分布。根据矿床勘查经验并结合成矿地质条件相似的邻区找矿实践,推断铜石地区金矿形成的极限深度为寒武系长青群朱砂洞组丁家庄白云岩段之底,即寒武系沉积盖层与前寒武系结晶基底之间的不整合面,不整合面之上是金矿形成的有利部位。根据地层真厚度,结合地层产状计算出地面至不整合面的铅直距离就是相应找矿靶区的金成矿预测靶区矿体埋藏深度,估算矿体埋藏深度为深部钻探工程设计提供了依据。     

Analysis of Lightweight Deflectometer Test Based on In Situ Stress and Strain Response

The lightweight deflectometer (LWD) is gaining acceptance and popularity as an in situ spot-testing device for quality control/quality assurance of earthwork compaction. Little research has been conducted to investigate the stress–strain response within the soil during LWD testing. Similarly, little research has been performed to examine the appropriateness of using homogeneous, isotropic, linear elastic half-space theory to estimate soil modulus (ELWD) from LWD results. With this aim, an array of vertical stress and strain sensors was placed within the soil to measure the stress–strain response during LWD loading. Measured in situ stress values matched well with stresses predicted using homogeneous, isotropic, linear elastic half-space theory. In situ stress data revealed that the contact stress distribution between the soil surface and loading plate is a function of the soil type. Measured in situ strain values did not correspond well with strains predicted using homogeneous, isotropic, linear elastic elasticity. An exponentially increasing modulus function was required to match experimental with theoretical elastic strains. The results indicate that the commonly used form to predict ELWD is inappropriate if the goal is to extract constitutive soil properties. Analysis of strain data suggests the LWD depth of influence (measurement depth) is 0.9–1.1 times the plate diameter.     

深部地下硐室与应力场轴变关系及其围岩损伤破裂分析

针对深部地下硐室与地应力场之间的轴变关系及其对硐室围岩损伤破裂的影响，建立了非均质围岩统计损伤力学模型；分析了不同断面形状、地层侧压系数、构造应力场对硐室围岩损伤破裂的作用机制和影响规律，定义了地层临界侧压系数；开展了三山岛金矿西岭矿区埋深2000 m地层硐室损伤破裂数值模拟，得到了该矿区深部地下硐室设计与布置原则。研究结果表明，“等应力轴比”情况下硐室围岩应力集中程度最小，损伤破裂区面积最小；地应力场是围岩损伤破裂的根本原因，侧压系数越大，硐室顶、底板处应力峰值越大，围岩以拉伸破裂为主，围岩损伤破裂区面积随侧压系数增大呈指数性增大；随着地层深度的增加，硐室临界侧压系数不断减小并趋近于1，深部地下硐室对水平构造应力更加敏感；构造应力场诱使围岩损伤破裂程度增大，损伤破裂区向构造应力场围岩应力集中区转移，使得硐室围岩发生冒顶和岩爆风险升高。因此，深部地下硐室的设计与布置应结合实际地应力条件，硐室轴向、断面形状、轴比尽可能符合地应力条件，从而最大程度降低地应力场对硐室围岩损伤破裂及稳定性的不利影响。      

Defining Yield from Bender Element Measurements in Triaxial Stress Probe Experiments

This paper describes the elastic response of a block sample of compressible Chicago glacial clay under a variety of stresses and its relationship with the deformation characteristics at relatively large strains. The elastic shear stiffness was obtained from bender element tests during consolidation and shearing in drained triaxial stress probe tests. An empirical correlation was established based on the elastic shear stiffness in a preyield condition. By comparing the empirical correlation with the measured elastic shear stiffness in the stress region during probing, the changes of elastic shear stiffness were investigated. The departure of elastic shear stiffness from values computed by the empirical relation based on K0 loading directly relates to the yielding characteristics of the clay. The large-scale change of soil structure at yielding alters the well-established relationship between the elastic shear stiffness and stresses in the preyield condition. The mechanical yielding response of clays can be detected based on the systematic analysis of the elastic shear wave velocities.     

一种板材小圆角胀压复合成形工艺解析

针对薄壁板材零件小圆角特征成形制造难的问题,提出了一种新型胀压复合成形工艺.其关键工艺参数为:预成形高度、预成形凹圆角大小和终成形胀形压力与背压凸模运行速度匹配关系.预成形高度决定了终成形小圆角的材料储备,预成形凹圆角的最佳值为充液拉深时凸模圆角可取的最小值,通过理论分析给出了预成形高度和预成形凹圆角的计算方法.建立了胀压复合成形过程力学模型,通过应力状态分析给出了不同胀形压力与背压凸模运行速度匹配关系下坯料圆角区变形状况.同时基于有限元模拟和工艺试验,研究了预成形高度和终成形胀形压力与背压匹配路径对试验件成形质量的影响,验证了理论分析的准确性,并证明了该新工艺的适用性.      

含铈马氏体时效钢带材的织构与弹塑性各向异性

采用织构的ＯＤＦ分析方法，研究了含铈马氏体时效钢冷轧带材、时效与固溶等处理后织构地的转变规律，以织构作权重函数理论预估了弹性各向异性（弹性模量）和塑性各向异性比（ｒ值），并讨论了织构与弹塑性各向异性的关系。     

Effects of Pore Position in Depth on Stress/Strain Concentration and Fatigue Crack Initiation

The stress field around a pore was analyzed as a function of the pore position in depth in the surface of a linear elastic solid using finite element modeling. It was found that the pore depth dominated the stress field around the pore on the surface and that the maximum stress was increased sharply when the pore intercepted with the surface at its top. Given the applied nominal stress, the magnitude of the maximum main stress only depended on the relative depth of the pore, while the pore size affected the stress distribution in the surface. An elastic-plastic model was also used to account for the yielding effect in the region where stress was over the yield strength. The results still indicated a significant maximum stress concentration when the pore was just buried underneath the surface, but with a lowered value than that of the linear elastic model. These results were consistent with the experimental observations that fatigue cracks were preferably initiated from pores and particles, which were just intercepted at their top with the sample surface or just buried beneath the surface.     

Measurements of Sediment Erosion and Transport with the Adjustable Shear Stress Erosion and Transport Flume

Soil and sediments play an important role in water management and water quality. Issues such as water turbidity, associated contaminants, reservoir sedimentation, undesirable erosion and scour, and aquatic habitat are all linked to sediment properties and behaviors. In situ analysis is necessary to develop an understanding of the erosion and transport of sediments. Sandia National Laboratories has recently patented the Adjustable Shear Stress Erosion and Transport (ASSET) Flume that quantifies in situ erosion of a sediment core with depth while affording simultaneous examination of transport modes (bedload versus suspended load) of the eroded material. Core erosion rates and ratios of bedload to suspended load transport of quartz sediments were studied with the ASSET Flume. The erosion and transport of a fine-grained natural cohesive sediment were also observed. Experiments using quartz sands revealed that the ratio of suspended load to bedload sediment transport is a function of grain diameter and shear stress at the sediment surface. Data collected from the ASSET Flume were used to formulate a novel empirical relation for predicting the ratio of bedload to suspended load as a function of shear stress and grain diameter for noncohesive sediments.     

矿井采深对涌水量的影响分析

分析矿井涌水的影响因素、矿井开采过程中周边岩体的地压变化,得出开采深度影响涌水的机理。采用水文地质比拟法原理,结合2组实例统计数据,应用采深比拟法和SPSS软件函数拟合,得出开采深度对矿井涌水量的影响。从水文地质、地质构造、矿体赋存条件、开采方法、矿岩的物理力学性质、自然环境等方面分析影响矿井涌水的因素;结合海姆定律、开挖应力变化范围说明采深和地压变化的关系,得出采深影响涌水的机理。拟合结果表明：外部因素的不同如岩溶裂隙发育,采用多种工程类比法,选取其中最优的进行预测,具有优越性。     

40Cr钢应力磁化过程中的磁化反转特征

金属磁记忆检测技术是一种可早期检测铁磁构件应力集中程度的新方法,但进一步定量评价和广泛应用的瓶颈问题是复杂的应力磁化反转特征.对40Cr钢圆棒试件在不同最大拉力下进行反复加载-卸载拉伸试验,测定试件表面某确定点处漏磁场与拉应力的关系.试验结果表明,当试件处于弹性变形阶段时,漏磁场强度与拉应力的变化规律为线性关系;当试件受力超过屈服强度时,漏磁场强度与拉应力的变化规律变为折线,表现为先减小后增大再减小的应力磁化反转现象.随着最大拉力的增大,应力磁化反转极值点位置向较高拉应力方向移动,漏磁场强度最大变化量△Bmax也逐渐增大.     

Moderating effects of a craving intervention on the relation between negative mood and heavy drinking following treatment for alcohol dependence.

Objective: Negative affect is a significant predictor of alcohol relapse, and the relation between negative affect and drinking has been shown to be strongly mediated by alcohol craving. Thus, targeting craving during treatment could potentially attenuate the relation between negative affect and drinking. Method: The current study is a secondary analysis of data from the COMBINE study, a randomized clinical trial that combined pharmacotherapy with behavioral intervention in the treatment of alcohol dependence. Our goal in the current study was to examine whether a treatment module that targeted craving would predict changes in negative mood during the 16-week combined behavioral intervention (n = 776) and the relation among changes in mood, craving, and changes in heavy drinking during treatment and 1 year posttreatment. Results: Changes in negative mood were significantly associated with changes in heavy drinking during treatment (f2 = 0.78). Participants (n = 432) who received the craving module had significantly fewer heavy drinking days during treatment (d = 0.31), and receiving the module moderated the relation between negative mood and heavy drinking during treatment (f2 = 0.92) and 1 year posttreatment (f2 = 0.03). Moderating effects of the craving module were mediated by changes in craving during treatment. Within-subject analyses indicated significant pre- to postmodule reductions in negative mood. Additionally, postmodule craving significantly mediated the association between negative mood and heavy drinking during treatment and at posttreatment. Conclusions: The craving module of the combined behavioral intervention may weaken the relation between negative affect and heavy drinking by fostering greater decreases in craving during treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)