撞楔在高岭土矿过流砂层中的应用

通过工程实例,阐述了使用撞楔作超前支护在非煤行业井巷施工中过流砂层中的成功应用。并且证明了使用撞楔作超前支护过流砂层等松软岩层的可行性。     

沥青路面拥包三维指标计算方法

为全面、准确评价沥青路面拥包严重程度,实现三维指标的自动计算,利用室内三维激光检测设备获取高精度、高密度的拥包模型激光点云数据,采用Lowess算法进行数据预处理,再利用RANSAC算法获取拥包下底面轮廓数据,基于HARR矩阵建立拥包三维模型.在此基础上,利用高差法和微元逼近法分别计算了拥包的最大高度、下底面积、隆起体积与行车方向最大坡度等三维指标;对比轻、重两个严重等级的拥包三维指标计算结果,研究激光线纵向间距对指标计算误差的影响规律.结果表明:当激光线纵向间距为0.5 mm时,拥包最大高度、下底面积、隆起体积和行车方向最大坡度的相对误差分别不超过3.28%、2.17%、3.76%和1.97%;随着激光线纵向间距逐渐增大至10 mm,拥包三维重构模型产生部分缺失,导致拥包三维指标相对误差逐渐增大;当间距为5 mm时,三维指标计算最大相对误差分别为3.49%、4.65%和7.11%和7.27%;当间距为10 mm时,隆起体积和行车方向最大坡度的相对误差均超过10%;建议采用三维激光技术对拥包进行检测时,纵向间距设置不大于5 mm,以保证拥包三维指标计算结果准确性.三维指标计算方法可评价拥包严重程度,评估行车安全风险.     

湿陷性黄土的地基处理

介绍了湿陷性黄土的特征以及湿陷性黄土地基的处理原则及目的，论述了该地基的多种处理方法，并对比了各种方法的使用范围、局限性及优缺点，以正确选用地基处理法，保证地基处理效果。     

压力注浆修补混凝土结构缺陷的应用

采用压力注入水泥浆的方法,对混凝土结构缺陷进行补强的应用与效果。     

Molecular dynamics study on the viscosity of glass-forming systems near and below the glass transition temperature

Temperature-dependent viscosity is critical to decipher two profound questions in condensed matter physics, namely the glass transition and the relaxation of amorphous solids. However, direct measurement of viscosity over a large temperature range is extremely difficult. Here, using classical molecular dynamics (MD) simulations, we report a novel method to calculate the equilibrium viscosity of supercooled liquid both above and below the glass transition temperature (T_g) and to estimate the nonequilibrium viscosity of glass down to room temperature. Based on the shoving model, we derived an analytical formula showing that the shear viscosity in logarithmic scale changes linearly with the shear-induced variation in shear modulus or potential energy of the glass-forming system. The shear viscosity as a function of steady-state potential energy of liquid under different shear strain rates can be directly calculated in MD simulations; together with its equilibrium potential energy, one can extrapolate the zero-strain-rate equilibrium viscosity. We verified the proposed model by reliably calculating equilibrium viscosity near T_g of four glass-forming systems (Kob–Andersen system, silica, Cu_45.5Zr_45.5Al₉, and silicon) with different fragilities. Furthermore, our model can estimate the nonequilibrium viscosity of glass below T_g; the upper-bound nonequilibrium viscosity of amorphous silica and silicon at room temperature are calculated to be ~10³² and 10²⁵ Pa·s, respectively.     

湿陷性黄土地基的常用处理方法

文章介绍了湿陷性黄土常用的几种地基处理方法,适用范围及处理要点,并结合工程实例,指出应根据建筑物类别、黄土特征、施工条件等方面的综合因素确定具体处理方法。     

定向钻与顶管施工费用的对比分析

文章通过实际的案例,对比在施工工艺允许的条件下,定向钻穿越和顶管穿越的施工费用,并得出由此选择穿越工艺的一种思路。