高陡坡运输碾压混凝土抗分离溜管的 研制与应用

为解决黄花寨水电站大坝工程高陡坡碾压混凝土运输问题,根据混凝土拌和物流变体特征,通过试验研制出能改变混凝土运行状态、控制混凝土输送速度,并能使混凝土在输送过程多次拌和的抗分离溜管。该抗分离溜管结构简单、操作简便,运行安全,制作及使用费低,在高陡坡条件下输送碾压混凝土,可以防止混凝土分离、保证混凝土质量,具有良好的推广价值。     

大伙房输水工程取水头部竖井高边坡稳定分析 与加固处理方法

主要介绍了大伙房输水(二期)工程,取水头部竖井开挖过程中,针对实际地质状况,对高边坡 稳定性进行详细分析,采取了灌浆、支护等加固处理措施,边坡稳定监测结果表明,加固效果较好。     

坡脚位移与边坡安全系数关系数值模拟分析

为研究坡脚位移与边坡稳定安全系数的关系,利用ABAQUS有限元分析软件,建立边坡有限元模型,结合抗剪强度折减法,在改变坡顶均布荷载的情况下分别计算相应的边坡稳定安全系数,并在坡脚范围内选取3个点进行位移观测.观测结果表明:3个观测点各方向的位移均随安全系数的减小而非线性地增大,各点X方向位移的变化幅度比Y方向大,各点Y...     

边坡卸荷带岩体渗透特性分析——以三峡永久船闸高边坡为例

为了准确描述卸荷带岩体的渗透特性,以三峡永久船闸高边坡为例,应用其监测资料,引入应变指标,将岩体卸荷带划分为强卸荷变形带、弱卸荷变形带和卸荷应力应变调整带.观测资料的计算分析表明:与未开挖岩体相比,强卸荷变形带、弱卸荷变形带和卸荷应力应变调整带的渗透系数分别增大了3 138～330,92～27倍和8～1倍.对整个分析过程作了详细介绍.     

山区公路边坡防护技术研究

山区公路的建设可能造成边坡损坏隐患,需要及时予以防护和整治。分析总结了边坡破坏类型、原因、主要处理原则及常用边坡防护形式和具体措施。皂市水库库区公路某边坡在水库蓄水后,安全系数不足,存在边坡崩滑体整体失稳的可能性,经过对各种治理方案的优缺点比较,决定采用“削方减载+坡面锚固护坡+地表截排水”的治理方案。该边坡经过处理后,安全系数得到提高,保证了皂市水库蓄水后公路运行的安全。     

粉喷桩在防潮堤工程中的应用

结合东营市莱州湾西岸防潮堤的工程地质条件,通过方案比较,堤基处理中采用粉喷桩技术,即:上游粉喷桩下游反压平台加固方案,实施后取得了良好的效果.     

河道生态护坡技术在宜春市城市防洪工程中的运用

根据国内有关城市河道治理的先进经验,采用了生态护坡技术在江西省宜春市城市防洪工程中的应用,取得显著效果.     

新疆北部某水电站导流洞进口高边坡塌方处理

某水电站是在建的二等大(2)型工程,导流洞在开工后进口发生了部分塌方及在进口上部发现裂缝,在考虑到对导流洞进口施工期的影响,针对施工期的特点采取治理措施进行处理后,导流洞进口边坡稳定且运行正常.     

自进式中空注浆锚杆在班多水电站施工中的应用

水利工程及各类地下工程中普遍存在着软弱围岩、断层破碎带等复杂地质条件,给岩锚施工带来了极大的困难,特别是在塌孔严重和需要特长锚杆的情况下,普通的砂浆锚杆施工难度大。文章结合班多水电站导流明渠边坡开挖支护施工,阐述了自进式中空注浆锚杆在岩石破碎、黏土岩等复杂地质条件下替代普通砂浆锚杆,能够克服普通砂浆锚杆施工进度缓慢、无法插杆、塌孔等问题,保证围岩的整体稳定。     

Establishing spatial trends in water chemistry and stable isotopes (δ15N and δ13C) in the Elwha River prior to dam removal and salmon recolonization

Two high‐head dams on the Elwha River in Washington State (USA) have changed the migratory patterns of resident and anadromous fish, limiting Pacific salmon to the lower 7.9 km of a river that historically supported large Pacific salmon runs. To document the effects of the dams prior to their removal, we measured carbon and nitrogen stable isotope ratios of primary producers, benthic macroinvertebrates, and fish, and water chemistry above, between and below the dams. We found that δ¹⁵N was significantly higher in fish, stoneflies, black flies, periphyton and macroalgae where salmon still have access. Fish and chloroperlid stoneflies were enriched in δ¹³C, but the values were more variable than in δ¹⁵N. For some taxa, there were also differences between the two river sections that lack salmon, suggesting that factors other than marine‐derived nutrients are structuring longitudinal isotopic profiles. Consistent with trophic theory, macroalgae had the lowest δ¹⁵N, followed by periphyton, macroinvertebrates and fish, with a range of 6.9, 6.2 and 7.7‰ below, between, and above the dams, respectively. Water chemistry analyses confirmed earlier reports that the river is oligotrophic. Phosphorous levels in the Elwha were lower than those found in other regional rivers, with significant differences among regulated, unregulated and reference sections. The removal of these dams, among the largest of such projects ever attempted, is expected to facilitate the return of salmon and their marine‐derived nutrients (MDN) throughout the watershed, possibly altering the food web structure, nutrient levels and stable isotope values that we documented. Published in 2010 by John Wiley & Sons, Ltd.