圭嘎拉高海拔隧道施工人员体力劳动强度评价

为探究圭嘎拉高海拔隧道施工人员体力劳动强度水平,评价施工工序劳动强度,选择圭嘎拉隧道进口段（海拔4 300 m）及1#斜井段（海拔4 560 m）的施工人员作为测试对象,分别测量不同工序下施工人员的生理指标（心率、血氧饱和度、耗氧量）。基于耗氧量计算能量代谢率,进而计算各工序的劳动强度指数。结果表明： 1）260 m的海拔高差造成的施工综合劳动强度指数差异具有统计学意义（P<0.05）; 2）二次衬砌钢筋绑扎是所测施工工序中劳动强度最大的工序,该工序下施工人员的心率、血氧饱和度和平均能量代谢率都出现超过卫生限值的情况,劳动强度指数达到35（极重）; 3）海拔为4 300~4 560 m时,隧道各施工工序劳动强度大部分为中度-极重度。     

斜拉索-磁流变阻尼器多性能约束下的减振控制算法

提出一种极点和方差指标约束下的斜拉索-磁流变减振控制算法。基于Halmiton原理与切比雪夫级数求解方法建立斜拉索-阻尼器减振控制系统状态空间方程。以极点表达减振控制快速性和稳定性约束,以方差表达小振幅和振速约束,基于凸优化理论,给出满足相容快速性、稳定性、小振幅以及振速指标约束下的磁流变半主动减振控制算法。最后,以某斜拉桥C20号斜拉索为例进行仿真验证。结果表明,给出的减振控制算法能保证斜拉索在随机外界激励下的快速性稳定性,且有效抑制拉索的振幅,减振效果良好。     

带扰动观测器的船舶轨迹跟踪自适应动态面滑模控制

针对遭受未知外部环境扰动的三自由度全驱动船舶轨迹跟踪控制问题,设计一种带扰动观测器的自适应动态面滑模控制方法。该方法构造扰动观测器估计未知扰动,并对控制量进行前馈补偿,采用σ修正泄漏项的自适应律估计扰动观测误差的界以提高控制精度,结合动态面技术解决传统反演法的微分爆炸问题,并选取李雅普诺夫函数证明该控制器可保证闭环系统内所有信号的一致最终有界性。基于一艘供给船舶进行仿真试验,结果表明,所设计的控制器输出合理有效且跟踪精度高,在工程实际中具有一定的参考价值。     

Model Test on Grouting Law in Dynamic Water-Rich Sand Layers by the Electric Resistance Method北大核心CSCD

In order to study the diffusion law of grouting slurry in the water-rich sand layer under flowing water conditions, a grouting test model consisting of a main test system, a grouting system, and a measurement system was developed. And for detecting the diffusion scope of the grouts, a new resistivity method was proposed. It is found that the relationship between grouting pressure and grouting rate during the test is strong. Under hydrodynamic conditions, the grouting slurry diffuses elliptically. Due to gravity and the effect of the upper water flow, the center of gravity of the ellipsoid is below the grouting outlet, and the grouting effectively improves the physical and mechanical properties of water-rich sand bodies. At the same time, the resistivity method has a good application effect on the detection of grouting diffusion range. The range of slurry diffusion obtained by the resistivity method is basically consistent with the boundary of the stone body after excavation, indicating that the resistivity method is reliable for detection of grouting range in dynamic water-rich sand layer. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

Effect of Seismic Parameters on the Safety Factor for an Underground Cavern北大核心CSCD

In order to quantitatively evaluate the safety of the surrounding rock of an underground cavern under seis-mic load, a comprehensive evaluation method for the stability of surrounding rock is proposed based on the general safety factor and point safety factor. A calculation method for the general safety factor of a cavern based on the prin-ciple of shear strength reduction of a rock mass is given, the run-through of the plastic zone between the main power-house and main transformer room is presented as a critical criterion for the overall instability of the cavern, and the general safety factor is obtained by searching for the reduction coefficient. A point safety factor calculation method based on the Mohr-Coulomb yield criterion is given. The influence of different seismic input parameters on the general safety factor of the cavern and the point safety factor of key positions are studied based on an underground power-house cavern of a hydropower station in Southwest China. The results show that the quantitative evaluation method for the stability of the surrounding rock based on the safety factor is feasible and can reflect the general safety de-gree and local safety degree of different positions of the cavern for different working conditions. It is found that the general safety factor of the cavern and the point safety factor of key positions decrease with an increase of the ampli-tude and duration of a seismic wave while they increase with an increase of the incident angle; additionally, the low frequency of a seismic wave has a great influence on the cavern while the high frequency has little effect. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

航道治理建设规划环境影响识别及指标体系建立

针对航道治理建设规划环境影响识别及指标体系建立问题,对长江干线"十三五"航道治理建设规划环境影响评价成果进行分析研究,采用系统分析、生态因子识别、生态影响判别等方法,得出规划要素与资源、环境要素之间的关系,并结合环境目标提出评价指标体系,可为航道规划环境影响评价提供参考和借鉴。     

制动器在水力式升船机中的应用

依托景洪升船机工程,探讨水力式升船机制动器的应用。通过对比分析电力驱动和水力驱动式升船机制动器的布置特点及工作方式,阐述制动器在水力式升船机中面临的新的技术问题,据此对水力式升船机制动器的制动力、同步性以及制动方式提出设计指标和要求,并探讨制动器的使用范围。建议水力式升船机制动器采用常开式,升船机正常运行时,制动器在船厢上、下游对接时投入使用。     

基于模糊理论的船舶复合碰撞危险度计算

基于船舶领域和动界的概念,在船舶碰撞几何原理的基础上,利用模糊规则和模糊综合评价方法,本文提出一种船舶复合碰撞危险度的计算方法.确定最近会遇距离(DCPA)、最近会遇时间(TCPA)、两船距离、相对方位、船速比5个主要因素的隶属度函数,并考虑航行区域状况、能见度情况和船舶的操纵性能等对船舶碰撞危险度的隶属度函数修正.用原始数据对3种不同会遇态势进行仿真和对3种不同碰撞危险度计算结果分析比较,结果表明该方法的有效性.     

高压齿轮泵浮动侧板的动态平衡机理

针对高压齿轮泵浮动侧板磨损问题,在解析齿轮泵内部流场的基础上重点研究了浮动侧板反推力作用点变化规律和导致侧板产生倾覆力矩的关键因素。以某型号高压大排量齿轮泵为模型,运用CFD软件解析齿轮泵内部流场并根据侧板结构特点建立压紧力和反推力的求解微分方程,求得一个轮齿啮合周期内的侧板倾覆力矩变化规律,同时通过建立齿轮泵工作腔压力测试系统对该理论分析结果进行验证,额定工况下：试验值与理论值误差为4.18%,当轮齿转角φ=14°时倾覆力矩达到最大值Ms=82.16N?m。该研究为高压大排量齿轮泵浮动侧板倾覆力矩计算和侧板结构优化设计提供了理论基础和技术支撑。     

路基土动态模量试验研究

采用UTM-100动态伺服液压材料试验系统,对路基土进行室内三轴重复加载试验,测试路基土动态回弹模量,分析了含水量、侧向应力、偏应力对回弹模量的影响关系,为制定路基土动态回弹模量的测试方法和取值标准提供了参考.