长江重庆大沙坝采砂对航道的影响

以重庆市大渡口区大沙坝采砂区为例,采用二维水流数学模型对拟定的采砂区采砂后工程河段的水流条件进行模拟计算,就工程河段的航道条件及水域条件进行了分析。结果表明:按照设计的采砂方式和采砂工程量对该河段的航道基本不会带来负面影响。     

桩-土-上部结构共同耦合作用下弹塑性地震反应分析

针对某框架结构进行了在地震作用下桩-土-上部结构共同耦合作用时的上部结构弹塑性动力特性和规律的研究。结果表明:是否考虑桩-土-上部结构共同耦合作用时的弹塑性地震反应分析对计算结果有较大的影响;考虑桩-土-上部结构共同作用后柱应力在不同的楼层有放大现象,按折减系数方法来考虑相互作用并非总是安全和合理的,设计时应充分考虑弹塑性地震反应的影响。     

桩-土-上部结构共同耦合作用下弹塑性地震反应分析

针对某框架结构进行了在地震作用下桩-土-上部结构共同耦合作用时的上部结构弹塑性动力特性和规律的研究.结果表明:是否考虑桩-土-上部结构共同耦合作用时的弹塑性地震反应分析对计算结果有较大的影响;考虑桩-土-上部结构共同作用后柱应力在不同的楼层有放大现象,按折减系数方法来考虑相互作用并非总是安全和合理的,设计时应充分考虑弹塑性地震反应的影响.     

乌江白涛河段郭母子滩航道整治

郭母子滩滩性复杂,属于两峡之间开阔河段滩险,浅、急、弯及险的碍航特性并存。采用疏浚与筑坝结合的整治方案,选取5组整治方案进行物理模型试验,根据整治前后的分流比、流速、流态等指标综合比较,最后推荐方案5为郭母子滩整治实施方案。     

某钢箱梁桥上跨既有铁路施工风险分析

某客运专线钢箱梁桥跨越既有铁路,部分墩身施工邻近既有线且高于既有桥梁顶面,钢箱梁采用顶推法施工。针对该桥施工方案,详细分析了施工工艺特点,对施工风险因素进行了辨识,并用层次分析法对已辨识的风险因素进行了重要性排序。最后,根据研究结果对此次施工提出了一些建议。     

北江千吨级航道整治研究：Ⅱ二维数学模型与整治河段通航水流条件分析

基于有限体积方法,建立平面二维水流数学模型,对北江白石窑枢纽坝下19km航道整治工程进行数值研究．运用实测水文资料对模型进行验证．验证结果表明：该模型精度符合规范要求．计算了整治工程实施前、后白石窑坝下游河段通航水流特性,分析了各级恒定流和非恒定流作用下整治工程对坝下游河段通航水流条件的影响．研究结果表明：实施整治工程后,整治河段水流条件得到了明显的改善,水流条件可以满足千吨级船舶的通航要求．     

基于输入输出线性化的航迹滑模控制及仿真

针对船舶航迹控制系统的非线性及易受外部干扰的特点,提出了一种基于输入输出线性化的航迹滑模控制策略。通过定义输出变量将非线性航迹控制系统转化为线性系统,然后采用指数趋近律的滑模控制方法设计控制器,使得设计的非线性控制律直观简洁,鲁棒性好。通过SIMULINK仿真验证了该算法的有效性。     

基于BP神经网络的卷烟零售量价控制研究

针对烟草营销中卷烟货源投放总量难以准确控制的问题,通过分析各区域货源投放量、实际销售量与零售价格之间的相互关系,采用BP神经网络预测,建立了卷烟零售量价控制模型,据此来调控各品类的投放量,测试结果表明有较好的预测准确度。     

霍林郭勒市珠斯花大街立交桥匝道静载检测与状态评估

通过对霍林郭勒市珠斯花大街立交桥匝道进行静载试验检测,得到实测数据,并通过与计算数据进行对比分析,得出了该桥结构处于良好的线弹性状态,强度和刚度都满足设计荷载标准要求,这个科学的评估结果。     

Experimental study on mechanical properties of weathered rock covered by loess

Based on dynamic triaxial test, the mechanical properties of the weathered rock covered by loess were studied. The cohesion value of weathered mudstone is far below that of the weathered sandstone, while the internal friction angle values are basically equivalent, about 30°. Compared with the undisturbed sample, the cohesion value of remodeling weathered rock sample decreases significantly. With the increase of moisture content, the strength of weathered mudstone is obviously decreased due to the influence of the water softening effect. This results illustrate that the bearing stratum is not easily affected by external disturbance in comparison to weathered mudstone. In the engineering, in order to ensure the good mechanical properties of the soil, more attention should be paid to keeping the water content constant, even to reducing the water content. The experiments show that the relations between shear stress and strain of weathered rock were nonlinear and the behavior of weathered rock can be expressed by the hyperbolic model. The initial modulus of undisturbed weathered rock, under the same consolidation conditions, is much greater than that of remodeling samples. Meanwhile, the initial dynamic elastic modulus of sandstone is also greater than that of the mudstone. The dynamic shear modulus ratios of the undisturbed sandstone, the undisturbed mudstone, as well as the remodeling mudstone have the normalization characteristics with the increase of dynamic shear strain. The damping ratio of mudstone is larger than that of the sandstone, and the damping ratio of remolding sample is also greater than that of the undisturbed mudstone. The mudstone has the bad mechanical properties as bearing stratum.