基于VMD和BSA-KELM的高陡边坡位移预测模型研究

边坡位移的时间序列曲线存在复杂的非线性特性,传统的预测模型精度不足以满足预测要求。为此提出了基于变分模态分解的鸟群优化-核极限学习机的预测模型,并用于河北省某水泥厂的边坡位移预测。该方法首先采用VMD把边坡位移序列分解为一系列的有限带宽的子序列,再对各子序列分别采用相空间重构并用核极限学习机预测,采用鸟群算法优化相空间重构的嵌入维度和KELM中惩罚系数和核参数三个数值,以取得最优预测模型。最后将各个子序列预测值叠加,得到边坡位移的最终预测值。结果表明：和KELM、BSA-KELM、EEMD-BSA-KELM模型相比,基于VMD的BSA-KELM预测精度更高,为边坡位移的预测提供一种有效的方法。     

Ultimate bearing capacity of strip footing resting on clay soil mixed with tire-derived aggregates

This study investigated the use of recycled tire-derived aggregate (TDA) mixed with kaolin as a method of increasing the ultimate bearing capacity ( UBC) of a strip footing. Thirteen 1g physical modeling tests were prepared in a rigid box of 0.6 m × 0.9 m in plan and 0.6 m in height. During sample preparation, 0%, 20%, 40%, or 60% (by weight) of powdery, shredded, small-sized granular (G 1–4 mm) or large-sized granular (G 5–8 mm) TDA was mixed with the kaolin. A strip footing was then placed on the stabilized kaolin and was caused to fail under stress-controlled conditions to determine the UBC. A rigorous 3D finite element analysis was developed in Optum G-3 to determine the UBC values based on the experimental test results. The experimental results showed that, except for the 20% powdery TDA, the TDA showed an increase in the UBC of the strip footing. When kaolin mixed with 20% G (5–8 mm), the UBC showed a threefold increase over that for the unreinforced case. The test with 20% G (1–4 mm) recorded the highest subgrade modulus. It was observed that the UBC calculated using finite element modeling overestimated the experimental UBC by an average of 9%.     

Delay compensated control of the Stefan problem and robustness to delay mismatch

This paper presents a control design for the one‐phase Stefan problem under actuator delay via a backstepping method. The Stefan problem represents a liquid‐solid phase change phenomenon which describes the time evolution of a material's temperature profile and the interface position. The actuator delay is modeled by a first‐order hyperbolic partial differential equation (PDE), resulting in a cascaded transport‐diffusion PDE system defined on a time‐varying spatial domain described by an ordinary differential equation (ODE). Two nonlinear backstepping transformations are utilized for the control design. The setpoint restriction is given to guarantee a physical constraint on the proposed controller for the melting process. This constraint ensures the exponential convergence of the moving interface to a setpoint and the exponential stability of the temperature equilibrium profile and the delayed controller in the norm. Furthermore, robustness analysis with respect to the delay mismatch between the plant and the controller is studied, which provides analogous results to the exact compensation by restricting the control gain.     

某住宅小区边坡渗水治理及综合利用

分析了某小区边坡渗水的原因，结合实际情况，介绍了边坡渗水的治理措施，并对渗水进行了收集综合利用，消除了边坡滑坡的安全隐患，取得了较好的社会效益和经济效益。     

龙滩水电站地下厂房进水口高边坡加固支护设计

龙滩水电站地下厂房进水口高边坡开挖坡高达435m，坡面面积达27万m^2，为典型的反倾向层状结构岩质高边坡。为了确保进水口坝段的稳定，必须保持边坡岩体有足够的稳定性，通过采取边坡轮廓设计，防渗、排水设计，加固支护设计及施工控制等一系列措施，确保边坡稳定。文章简要论述了边坡设计的原则、标准、高边坡轮廓设计、防渗排水系统、加固支护措施、施工控制等情况。     

模袋混凝土护坡在永定河滞洪水库工程中的应用

模袋混凝土护坡是一种新型的护面技术,具有整体性强、冲灌的混凝土强度可根据工程具体要求设计的优点.它克服了其它护面型式的诸多缺点,成为十分成熟的护面新技术.随着土工合成材料在水利工程上大面积推广应用,模袋混凝土护坡具有良好的应用前景.     

黄河龙青段主要环境工程地质问题分析思路

介绍了黄河上游龙青段主要环境工程地质问题的分析思路，以达到抛砖引玉，交流和提高电工程地质勘测水平的目的。     

Engineering Geological Problems of Levee Along Middle and Lower Reaches of Yangtze River

1　ＩｎｔｒｏｄｕｃｔｉｏｎＢｅｃａｕｓｅｏｆｔｈｅｃｏｍｐｌｉｃａｔｅｄｓｕｂｓｏｉｌｐｒｏｆｉｌｅ ,ｔｈｅｌｅｖｅｅａｌｏｎｇｍｉｄｄｌｅａｎｄｌｏｗｅｒｒｅａｃｈｅｓｏｆＹａｎｇｔｚｅ ,ａｂｏｕｔ 36 0 0ｋｍｌｏｎｇ ,ｈａｓｍａｎｙｈｉｄｄｅｎｐｅｒｉｌｓ .Ａｍｏｎｇｔｈｅｄａｎｇｅｒｏｕｓｅｖｅｎｔｓｄｕｒｉｎｇ 1998’ｓｆｌｏｏｄｓｅａｓｏｎｉｎｔｈｅｗｈｏｌｅｖａｌｌｅｙ ,12 .7%ｏｃ ｃｕｒｒｅｄａｌｏｎｇｔｈｅｔｒｕｎｋｓｔｒｅａｍｄｙｋｅｓ,ｏｆｗｈｉｃｈ 6 98ｗｅｒｅｔｈｅｍｏｓｔｄ…     

公路边坡培植柠条的探讨

介绍了河曲公路所处的自然环境 ,阐述了人工铲草的利与弊 ,进而提出了边坡培植柠条的效益分析 ,并对培植柠条的苗期管理及与养护生产的关系进行了介绍     

道路边坡生态防护初探

随着我国经济实力的增强和人们环保意识的提高，国家已经十分重视道路建设中的生态建设和环境保护。通过对已建道路边坡防护方式进行分析，找出了存在的问题，提出改善和提高道路边坡防护的方法，并通过工程实例进一步得到验证。