施工导流及围堰技术在水利水电工程施工中的标准应用

本文主要围绕水利水电工程施工导流和围堰技术的概述,重点分析了水利水电工程施工导流技术应用和围堰技术的具体应用。     

三峡工程三期RCC围堰工程

三期RCC围堰工程项目是确保三峡工程2003年蓄水、通航和发电目标按期实现的关键项目，也是右岸厂房坝段和右岸电站厂房等后续施工项目安全施工的保障。受施工通航、施工场地及工期条件等限制，三期RCC围堰的混凝土施工强度和上升高度均超过目前现有施工水平，针对这些难点开发出有效的处理工艺，保证了围堰工程的实施。     

加格达奇区橡胶坝导流及截流施工措施

本文通过对加格达奇橡胶坝工程施工导流的设计与施工,介绍水工建筑物施工导流的基本方法,主要包括装砂砾石编织袋护坡填筑、编织袋装砂砾石护脚、围堰填筑、截流护底、戗堤填筑。     

关于水利水电施工中现代新技术

水利水电工程质量是工程建设的关键,直接影响工程竣工后的安全运行。在水利水电施工中,根据工程实际情况,兼顾综合效益,合理应用AtuoCAD辅助设计技术、大体积碾压混凝土施工技术、施工导流与围堰技术、预应力锚固技术、光面爆破技术等现代新技术,能有效保证水利水电施工质量,加快工程施工进度,切实提高工程综合效益。     

水利工程施工导流及围堰技术

水利工程施工建设过程中围堰技术和施工导流作为重要构成,想要全面提升水利工程建设的质量,应该合理运用水利工程施工的围堰技术和施工导流技术施工,进而直接影响到水利工程正常运行。该文针对当前水利工程中的围堰技术和施工导流技术做出全面分析,再对这2项技术运用和施工工艺等进行阐述,从而为开展水利工程的施工、建设等工作提出具体见解。     

全段围堰导流技术在水利施工中的应用

近些年来,我国水利水电工程越来越多,在水利水电工程中,非常重要的一个组成部分就是施工导流,它会对施工程序、永久建筑物的型式和施工总进度产生直接的影响。导流设计在水利施工中,主要作用是对初期导流以及后期导流施工过程中的挡水和泄水问题进行解决,保证水利施工的整体质量。本文简要分析了全段围堰导流技术在水利施工中的应用,希望可以提供一些有价值的参考意见。     

过水围堰施工导流联合泄流管理决策支持系统

过水围堰施工导流联合泄流管理是典型的半结构化决策问题，为此设计开发了过水围堰施工导流联合泄流管理决策支持系统（CDDSS）。系统地介绍了CDDSS的结构框架、设计原则、开发思路、决策模式和基本功能，该系统由数据库子系统、模型库子系统、图形库子系统和人机界面四部分组成，此系统是建立在数学模型的基础上，综合利用系统科学、管理科学、施工导流的理论及方法的人机交互系统。工程实例分析表明，系统友好的用户界面帮助决策者/用户充分利用系统的功能做出有效的实时决策。     

水电施工导流技术的综述

导流是水利水电工程施工中的关键环节之一,施工情况复杂,影响因素较多,甚至有时直接会关系到整个工程的施工难度和进度,有时甚至部分影响到水工建筑物的形式选择和布置,故本文针对水利水电施工的导流问题,详细介绍了当前我国水利水电工程施工部分技术的新进展,同时详细说明了导流施工的八种形式及其应用环境,希望本文的介绍能为水利水电施工企业的导流施工带来一定的参考。     

浅析土石方工程挖掘机与自卸汽车的最佳配置

笔者结合南安市海峡科技生态城A片区项目施工的特点,根据土石方工程施工的实践与体会,分析了土石方工程施工机械的配置原则、选配方法,以挖掘机、自卸汽车为例,论述了配置过程中基本算法,为类似工程提供借鉴,降低施工成本,提高效率。     

贵州乌江思林水电站左岸导流洞工程K30溶洞段处理

乌江思林水电站导流方式为断流围堰、隧洞导流的导流方式，由于开工后的设计调整，左岸导流洞高出右岸导流洞6m（断面相同），主要承担大坝围堰建成后的汛期联和导流任务。左岸导流洞有两处大的岩溶管道（设计编号：K30、K31），其中K30岩溶系统在施工期内发生了塌方、涌水等事件，对施工影响极大，同时处理难度也较大。经咨询及分析计算，最后确定了分部处理方案，实施效果良好。     

三峡工程管理模式及混凝土技术研究

三峡水利枢纽是目前世界上规模最大的混凝土建筑物,混凝土总量近2800×104m3,除满足稳定性要求外,还需要满足泄洪、发电、航运等方面的特殊要求,具有结构复杂、施工强度高、技术标准高等特点.通过10年的工程实践,三峡工程建设管理初步形成了具有三峡工程特色的管理模式.为保证混凝土优质快速施工,研究和决策了若干新技术和新工艺, 论述了三峡工程的管理模式和三峡工程混凝土工程技术.     

Concrete cooling on dam construction for world's largest hydroelectric power stationLa réfrigération du béton pour la construction du barrage de la plus grande centrale hydro-électrique du monde

The cooling of concrete is very important for technical and economic reasons during the construction o3 large dams, particularly in hot climates. Some 12 million m³ of cooled concrete is being processed for construction of the largest hydroelectric power station in the world (12 600 MW), in South America, which necessitates large-scale concrete processing plants.The overall design, operation and detailed construction of the huge refrigerating installations are described. The necessity of cooling the concrete is dealt with, as are the possible methods for so doing.     

Concrete cooling on dam construction for world's largest hydroelectric power station

The cooling of concrete is very important for technical and economic reasons during the construction o3 large dams, particularly in hot climates. Some 12 million m³ of cooled concrete is being processed for construction of the largest hydroelectric power station in the world (12 600 MW), in South America, which necessitates large-scale concrete processing plants.The overall design, operation and detailed construction of the huge refrigerating installations are described. The necessity of cooling the concrete is dealt with, as are the possible methods for so doing.     

Damage distribution and size effect in numerical concrete from lattice analyses

Size effect on structural strength of concrete prisms subjected to three-point bending has been studied using the lattice model, which has been extended and now contains a realistic aggregate structure of concrete. The aggregate structure was obtained from CT-scans of real concrete prisms and overlaying the obtained image with a 3-dimensional hcp-lattice. The numerical analyses show that a size effect on structural strength exists for all studied aggregate densities and aggregate shapes. The size effect can be approximated with a Weibull model, where the main parameter, the Weibull modulus, depends on the concrete composition. The crack size distributions have been calculated and show a similar distribution as hypothesized before for fracture in ceramics. The results from the crack size distribution are helping to provide insight into the nature of the fracture process, which seems to differ from that hitherto assumed in cohesive crack models. After a weakening of the material through a multitude of microcracks, at peak load a single large crack propagates while loading continues in the softening regime. The presumed ‘cloud of microcracks’ advancing ahead of the macro-crack tip has not been found. Instead an alternative macroscopic model strategy, referred to as the 4-stage fracture model, is proposed.     

三峡工程通航建筑物技术设计审查

三峡工程是当代全球最大的水利工程,其中的每一项重大工程技术设计与施工建造,均可列为世界水利工程的难题和典型案例,是人类水利工程建设中的一笔宝贵财富。 文章根据1994年开始的三峡通航建筑物技术设计的全面审查,就通航建筑物总体布置,船闸输水系统和船闸水力学,永久船闸高边坡设计,永久船闸水工结构,升船机,技术设计阶段的科研工作成果等6个部分做了阐述和讨论。     

Robust positioning technique in low-cost DR/GPS for land navigation

This paper describes a dead-reckoning (DR) construction for land navigation and sigma-point-based receding-horizon Kalman finite-impulse response (SPRHKF) filter for DR/GPS integration system. A simple DR construction is adopted to improve the performance of both pure land DR navigation and DR/GPS integration system. In order to overcome the flaws of the extended Kalman filter (EKF), the sigma-point KF (SPKF) is merged with the receding-horizon strategy. This filter has several advantages over the EKF, the SPKF, and the RHKF filter. The advantages include the robustness to the system model uncertainty, the initial estimation error, temporary unknown bias, etc. The computational burden is reduced. Especially, the proposed filter works well even in the case of exiting the unmodeled random walk of the inertial sensors, which can occur in the microelectromechanical systems' inertial sensors by temperature variation. Therefore, the SPRHKF filter can provide the navigation information with good quality in the DR/GPS integration system for land navigation seamlessly.     

超大型陆上沉井封底施工技术

泰州大桥北锚碇沉井封底总方量超过30 000 m3,为目前国内立方量最大的水下封底混凝土施工工程,其施工难度大,现场组织要求高。从沉井清基、封底设备布置、封底混凝土施工工艺等方面概略介绍泰州大桥北锚碇沉井封底施工技术。     

论混凝土坝的几个重要问题

目前我国在建混凝土坝的高度、数量、规模均居世界第一位,文章就混凝土坝技术的几个重要问题进行讨论：（1）结束“无坝不裂"历史的关键技术;（2）应用氧化镁混凝土筑坝的两种指导思想和两种实践结果;（3）混凝土强度等级应用于混凝土坝欠妥,坝工混凝土仍以采用混凝土标号为宜;（4）我国特高拱坝的抗压安全系数偏低,应适当提高。（5）拱坝有限元等效应力问题。     

Mock-up experiments on permeability measurement of concrete and construction joints for air tightness assessment

Concrete permeability is subject to various test conditions, and on-site measurement at in situ structural scale is much preferable. This paper presents an experimental study to measure the permeability of concrete linings and their construction (placing) joints between old and new concretes using a novel in situ permeability testing system. Using the developed system, we performed in situ scale permeability tests of rectangular concrete specimens with dimensions of 500 × 500 × 2800 mm³, within which the construction joints were artificially placed. From this model experiment, we verified an effective applicability of the system to both low permeability concrete matrices and highly permeable construction joints thanks to its selective capability of gas or water permeability test, depending on the air/water tightness of tested materials. The experimental results presented in this paper also showed that the intrinsic permeability of the construction joint could be higher than that of the concrete matrices by orders of magnitude (10¹–10⁴ times), but it could be reduced to as low as those of the concrete matrix by pasting a bonding agent on the interfacing surfaces. As a result of geomechanical monitoring during the experiment, the opening displacement of construction joints with relatively higher stiffness values showed a reversible deformation when the gas injection pressure was unloaded, which is much preferable in a storage performance perspective of underground lined rock caverns.     

废弃混凝土再生利用技术的研究进展

废弃混凝土再生利用对于保护环境、减少资源与能源浪费以及实现可持续发展具有重要意义。从混凝土再生骨料对混凝土性能的影响、混凝土再生骨料的应用、提高再生混凝土性能的方法3个方面介绍了目前国内外废弃混凝土再生利用技术的研究现状。指出除了进一步加大相关试验及基础理论研究外,国家以及相关机构还应在政策、资金等方面进行支持,并建立废弃混凝土再利用的具体实施标准、规范等,最终实现废弃混凝土"零排放"。