数码相机莫尔效应位移测量算法的改进

针对正弦函数拟合两期相机效应莫尔条纹图像同名行像素的两条灰度曲线时没有考虑曲线之间的相关性问题,提出改进方法,即:两期数据联合平差,并附加两曲线角频率相等这一约束条件。采用附有约束条件的联合平差法计算的结果与y轴的选取位置无关,精度得到改善,特别是在两期相片曝光量相差较大时,目标位移量的计算精度显著提高。实验结果表明:改进算法计算的位移量和精度不随y坐标轴位置的变化而变化,在两期图像曝光量不等时,计算精度提高明显。     

Interference effect of two closely-spaced shallow strip foundations on geogrid-reinforced sand

Summary Geotextiles and geogrids are now being used extensively in many civil engineering construction works. This study presents some laboratory model test results for the ultimate bearing capacity of an isolated, and two closely-spaced, strip foundations resting on unreinforced sand, and sand reinforced with layers of geogrid. Based on the model test results, the variation of the group efficiency with the centre-to-centre spacing of the foundation has been determined.     

薄基岩条带开采覆岩与地表移动数值模拟研究

通过数值模拟模型，分析了薄基岩条件下条带开采引起的覆岩破坏机理、地表的下沉和水平变形等移动变形值，揭示了薄基岩条带综放开采引起的上覆岩土层的应力场、位移场及地表的移动变形规律，为薄基岩条件下条带开采覆岩与地表移动变形的工程地质机理的研究奠定了基础。     

Seismic uplift capacity of strip anchors in soil

Uplift capacity of horizontal strip anchors in soil embedded under an inclined ground surface has been obtained under seismic conditions. Limit equilibrium approach with logspiral failure surface together with pseudo-static seismic forces has been adopted. The results have been presented in the form of seismic uplift capacity factors as functions of ground inclination, embedment ratio, angle of internal friction of the soil and seismic acceleration coefficients. The uplift capacity factors have been worked out separately for cohesion, surcharge and density components. Effect of the vertical seismic acceleration coefficient has been found to always reduce the uplift capacity whereas the effect of horizontal seismic acceleration coefficient has been found to reduce the uplift capacity in most of the cases. The obtained results of seismic uplift capacity factors are found to be the minimum when compared with the results available in literature on the basis of planar failure surface. This revised version was published online in July 2006 with corrections to the Cover Date.     

真空联合堆载预压法加固水工建筑物软基效果检验

介绍了真空联合堆载预压法加固软土地基的特点,探讨了该方法的加固机理,论证了淮河入海水道张马涵闸软基处理采用真空联合堆载预压法的依据。根据现场的监测资料(包括表面沉降、分层沉降、水平位移、孔隙水压力、真空度等)和原位测试(包括CPT、十字板试验、静载试验和标准贯入试验等)资料,以及土工试验成果的分析和比较,对张马涵闸软基的加固效果进行分析和检验,结果证明,该法完全满足设计要求,为该工法在类似工程软基处理的推广应用提供参考。     

Mechanical responses of metallic strip flexible pipes subjected to pure torsion

Metallic strip flexible pipes (MSFP), a relatively new style of unbonded flexible pipes, are considered as an attractive alternative to traditional submarine pipes. Pipelines will inevitably confront torsion load which may affect the integrity and safety during their installation and application. Throughout this paper, the mechanical behavior of MSFP subjected to pure torsion is investigated by both experimental and numerical methods. Results from these two methods are essentially in agreement with each other. The finite element method (FEM) can be adopted to predict the failure torque of MSFP under torsion and analyze the detailed stress conditions of each layer. In addition, the effects of boundary conditions, layout manners of steel strips, friction coefficients between contact surfaces, twist directions and tension loads are discussed. The obtained conclusions will benefit cross-section design of MSFP and relative practical engineering.     

条带法在底板承压水上采煤中应用的数值模拟研究

近年来,条带法被用来作为承压水上采煤的主要采煤方法。针对承压水上采煤问题,应用流固耦合原理,将孔隙介质中孔隙压力与应力建构在统一的本构模型中,平行计算应力场与渗流场,其实质是煤岩体体积应变对孔隙的影响通过流动本构定律加以反映;反之孔隙压力的变化可引起煤岩体变形。应用FLAC有限差分软件对条带式和长壁式采煤方法的应力发展和岩体破坏情况进行模拟并进行比较分析,证明条带法在降低由采动引起的应力影响范围和程度,从而减小煤层底板破坏程度和范围(主要是深度)的有效性,为合理确定承压水上采煤的开采方案提供了理论依据。     

成层软黏土地基的固结沉降计算分析

针对实际工程中软黏土地基的成层特性及竖井有时并未打穿软土层情况,采用太沙基一维固结理论和巴伦固结理论的基本假定,利用固结度联系孔压与变形,提出一种简化成层软黏土地基的固结沉降计算方法,对竖向排水地基的固结度及沉降等进行预测。对计算的几个关键问题进行探讨：如固结系数的反演选择、竖井未打穿土层时,竖井底部成层地基固结度计算、压缩土层厚度选取等问题。在上述理论的基础上,用FORTRAN语言编写排水竖井固结程序CONSOL,在工程实践中得到应用,取得良好的效果。     

超载预压法阈值问题的室内试验研究

通过室内模拟试验,对超载预压法的超载比及超载作用时间进行研究,以期达到用最经济的方式（超载比与超载作用时间的合理组合）实现减少后续沉降及沉降差的目的     

大冶铁矿东露天采场边坡岩体力学参数研究

介绍了三十多年来在大冶铁矿东露天采场南、北帮边坡岩体中进行的岩体抗剪强度现场测试方法、技术及试验结果,并汇总出一套历次为边坡稳定性分析采用的抗剪强度参数值,为岩体力学参数数据库增加了大量信息。