土工击实试验中预估最优含水率的方法

通过对以往所做的土工击实试验数据进行分析与统计,得到不同试验条件下的预估最优含水率的定量计算方法,为今后的工作提供指导.     

土工液塑限试验中的新方法应用与比较

针对公路与水电土工试验规程中所采用的作图法确定液塑限值而带来的诸多不便,采用数学解析法、最小二乘法、回归分析法计算液塑限试验数据,并将其编制成QBASIC程序上机处理,由此确定出的液限、塑限值较传统方法方便、快捷、准确。同时对公路与水电土工试验规程中所采用的不同圆锥下沉深度而计算出的液塑限值进行了比较。     

AutoCAD 二次开发在土工试验中的应用

利用Visual LISP语言对AutoCAD进行二次开发,提出解决室内土工试验自动化数据采集、计算、曲线自动生成新方案;介绍程序技术特点、算法优劣判定、浮动图形菜单制作等编程技巧,具有鲜明的技术创新点和广阔的市场前景.该程序已应用于企业的实际工程中,填补了国内该领域的一个空白.     

KTG全自动系统在土工试验中的应用

KTG全自动试验采集系统在土工试验中应用,不仅大大提高了试验精度,而且减轻了劳动强度,缩短了试验周期,提高了效率和效益。     

土体固结理论在工程实际中的应用研究

路基质量的好坏决定着道路的使用寿命,随着路面车辆的运行,路基土体由于受荷载作用,其孔隙中的水份会缓慢渗出,土体中的有效应力会逐步增大,超静孔隙水压力逐步消散直至完全消失,即固结作用,而路基土的压实度是由土体的最大干密度和最佳含水率控制的。因此,在工程实际中,最大干密度和最佳含水率便可以认为是固结理论的宏观表现。     

压实条件及细粒含量对回填土抗震稳定性的影响

为了深入研究压实条件与细粒含量对土抗震稳定性的综合影响,对不同级配的土开展了循环荷载三轴试验,探讨了含水率、干密度、饱和度对其不排水动强度的影响规律及机理,分析了不同细粒含量压实土所呈现的动强度特征差异,并引入以压实度和饱和度为自变量的方程来定量表述动强度。研究结果表明:在一定的压实能量下,达到最大干密度的土并不一定具有最大的不排水动强度,对于细粒含量较大的土,动强度由压实度和饱和度同时决定,而对于细粒含量较小的土,动强度基本只受压实度的影响;利用动强度预测方程可以在不掌握击实曲线的前提下预测压实土的不排水动强度,为抗震稳定性评价提供依据。     

倾斜试验中初稳性高度最小二乘法计算方法解析及应用

根据最小二乘法原理推导了倾斜试验中初稳性高最小二乘法计算的正确公式，研究了应用最小二乘法判断倾斜试验中误差的计算方法。     

基于遗传算法的非线性最小二乘在纯方位系统中的应用

鉴于非线性最小二乘法在国内目标运动分析中应用较少的现状,研究了纯方位系统的非线性最小二乘解法,提出了遗传算法的求解方法.结合实际问题设计了具体的遗传算法,并用实例进行了仿真分析.通过仿真结果的比较,可以看出用遗传算法的非线性最小二乘法明显优于线性方法,也优于非线性方法的梯度解法.     

Determination of the transportable moisture limit of iron ore fines for the prevention of liquefaction in bulk carriers

In 2013, over 500 million metric tons of Iron Ore Fines (IOF) were transported around the world using bulk carriers. Under certain conditions IOF, while being transported, can possibly undergo liquefaction. Since 2006, there has been eight reported bulk carrier casualties possibly caused by the liquefaction of IOF. The objective of this study is to evaluate, compare and verify the limitations and relevance of the Proctor/Fagerberg, Flow Table and Penetration test methods that are used to determine the Transportable Moisture Limit (TML) of IOF. The TML is the maximum gross water content that bulk cargoes, including IOF, may contain while being transported at sea without being at risk of liquefying. A thorough literature review, along with laboratory research, was carried out to compare the TML results from the three leading test methods to determine whether they produce reliable results when testing IOF. The study concludes that the three test methods, as stated in the 2012 International Maritime Solid Bulk Cargoes Code, are unverified and therefore not appropriate for testing IOF. This is due to the variation in the results produced by the three test methods and also due to the difference in the physical properties of IOF when compared with the materials that were originally intended for testing. It is noted that the TML alone may not control the potential liquefaction of IOF and further studies, regarding the physical properties and system variables, which cause the material to liquefy, are required to determine the liquefaction potential of IOF.