Financial Calculation Problems and Countermeasure Analysis of Large-Scale Engineering Construction Projects

The financial aspects of large-scale engineering construction projects profoundly influence their success.Strengthening cost control and establishing a scientific financial evaluation system can enhance the project’s economic benefits,minimize unnecessary costs,and provide decision-makers with a robust financial foundation.Additionally,implementing an effective cash flow control mechanism and conducting a comprehensive assessment of potential project risks can ensure financial stability and mitigate the risk of fund shortages.Developing a practical and feasible fundraising plan,along with stringent fund management practices,can prevent fund wastage and optimize fund utilization efficiency.These measures not only facilitate smooth project progression and improve project management efficiency but also enhance the project’s economic and social outcomes.

Key techniques for evaluation of safety monitoring sensors in water conservancy and hydropower engineering

For the evaluation of construction quality and the verification of the design of water conservancy and hydropower engineering projects, and especially for the control of dam safety operation behavior, safety monitoring sensors are employed in a majority of engineering projects. These sensors are used to monitor the project during the dam construction and operation periods, and play an important role in reservoir safety operation and producing benefits. With the changing of operating environments and run-time of projects, there are some factors affecting the operation and management of projects, such as a certain amount of damaged sensors and instability of the measured data. Therefore, it is urgent to evaluate existing safety monitoring sensors in water conservancy and hydropower engineering projects. However, there are neither standards nor evaluation guidelines at present. Based on engineering practice, this study examined some key techniques for the evaluation of safety monitoring sensors, including the evaluation process of the safety monitoring system, on-site detection methods of two typical pieces of equipment, the differential resistor sensor and vibrating wire sensor, the on-site detection methods of communication cable faults, and a validity test of the sensor measured data. These key techniques were applied in the Xiaolangdi Water Control Project and Xiaoxi Hydropower Project. The results show that the measured data of a majority of sensors are reliable and reasonable, and can reasonably reflect the structural change behavior in the project operating process, indicating that the availabilities of the safety monitoring sensors of the two projects are high

3-D Fracture Network Modelling in Hydropower Engineering Based on Optimal Monte Carlo Simulation

Effectively and accurately modelling the spatial relation of fracture surfaces is crucial in the design and construction of large hydropower dams having a complex underlying geology. However, fracture surfaces are randomly formed and vary greatly with respect to their spatial distribution, which makes the construction of accurate 3-D models challenging. In this study, we use an optimal Monte Carlo simulation and dynamic conditioning to construct a fracture network model. We found the optimal Monte Carlo simulation to effectively reduce the error associated with the Monte Carlo method and use dynamic conditioning to ensure the consistency of the model with the actual distribution of fractures on the excavation faces and outcrops. We applied this novel approach to a hydropower station on the Jinshajiang River, China. The simulation results matched the real sampled values well, confirming that the model is capable of effectively and accurately simulating the spatial relations in a fracture network. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg.

Design of High Precision Horizontal Control Network for Large-Scale Hydropower Project

A new solution of combination network of GPS and high precise distance measurements with EDM is proposed. Meanwhile, it’s inadvisable only using GPS network without distance measurements. Three schemes: terrestrial network, GPS network and combination network are discussed for horizontal control network design of Xiangjiaba Dam in view of precision, reliability, coordinate and outlay in detail.

Analysis on the Problems of Solutions of Water Conservancy & Hydropower Engineering Cost Management

With the continuous development of society and economy in China, the number of water conserv ancy & hydropower engineering in China increases unceasingly and China s water conserv ancy industry also enters into the stage of rapid development. The construction of water conserv ancy & hydropower engineering promotes social and economic development, so in order to safeguard the benefits of the engineering, cost management shall be done well, which is also an important channel for companies engaging in water conservancy & hydropower engineering to obtain economic benefits. Based on this the paper firstly investigates the problems in water conserv ancy & hydropower engineering cost management and then brings up relevant solutions.

Visualization aided system of hydropower engineering management

For the purpose of realizing the information visualization of hydropower engineering management, we construeted three kinds of graphics models sorted by hierarchy for system modelling, employed the construction simulation system to simulate the real-time construction behaviours, introduced the graphics rendering system to organize and update the virtual scene, and designed the interaction system to respond to the user-initiated and simulation-initiated events. So, the real-time, interactive visualization aided system of hydropower engineering management is developed. Eventually, the effectiveness and capabilities of the system are showed through the application examples in China.

Safety evaluation system for hydraulic metal structures based on knowledge engineering

A comprehensive safety evaluation system taking the most influential factors into account has been developed to evaluate the reliability of hydraulic metal structures. Applying the techniques of AI and DB, the idea of a one-machine and three-base system is proposed. The framework of the three-base system has been designed and the structural framework constructed in turn. A practical example is given to illustrate the process of using this system and it can be used for comparison and analysis purposes. The key technology of the system is its ability to reorganize and improve the expert system＇s knowledge base by establishing the expert system. This system utilizes the computer technology inference process, making safety evaluation conclusions more reasonable and applicable to the actual situation. The system is not only advanced, but also feasible, reliable, artificially intelligent, and has the capacity to constantly grow.

Modified Augmented Lagrange Multiplier Methods for Large-Scale Chemical Process Optimization

Chemical process optimization can be described as large-scale nonlinear constrained minimization. The modified augmented Lagrange multiplier methods (MALMM) for large-scale nonlinear constrained minimization are studied in this paper. The Lagrange function contains the penalty terms on equality and inequality constraints and the methods can be applied to solve a series of bound constrained sub-problems instead of a series of unconstrained sub-problems. The steps of the methods are examined in full detail. Numerical experiments are made for a variety of problems, from small to very large-scale, which show the stability and effectiveness of the methods in large-scale problems.

Measures for controlling large deformations of underground caverns under high in-situ stress condition--A case study of JinpingⅠhydropower station

The Jinping I hydropower station is a huge water conservancy project consisting of the highest concrete arch dam to date in the world and a highly complex and large underground powerhouse cavern. It is located on the right bank with extremely high in-situ stress and a few discontinuities observed in surrounding rock masses. The problems of rock mass deformation and failure result in considerable challenges related to project design and construction and have raised a wide range of concerns in the fields of rock mechanics and engineering. During the excavation of underground caverns, high in-situ stress and relatively low rock mass strength in combination with large excavation dimensions lead to large deformation of the surrounding rock mass and support. Existing experiences in excavation and support cannot deal with the large deformation of rock mass effectively, and further studies are needed. In this paper, the geological conditions, layout of caverns, and design of excavation and support are first introduced, and then detailed analyses of deformation and failure characteristics of rocks are presented. Based on this, the mechanisms of deformation and failure are discussed, and the support adjustments for controlling rock large deformation and subsequent excavation procedures are proposed. Finally, the effectiveness of support and excavation adjustments to maintain the stability of the rock mass is verified. The measures for controlling the large deformation of surrounding rocks enrich the practical experiences related to the design and construction of large underground openings, and the construction of caverns in the Jinping I hydropower station provides a good case study of large-scale excavation in highly stressed ground with complex geological structures, as well as a reference case for research on rock mechanics.

New developments of technology in rock engineering in China

In terms of rock engineering and technology in hydropower construction,the slope stability and monitoring techniques for high slopes of Three Gorges Project,the stability and support technology for high slopes of hydropower projects in deep river valley,the stabilization techniques for underground cavern group with large span and high side walls are introduced in this paper.As for rock engineering and technology in highway and railway construction,the Qinghai-Tibet Railway — new construction techniques in permafrost,the support techniques for large squeezing deformation in Wuqiaoling Tunnel,the construction techniques for tunnels in alpine and high-altitude region,the geological prediction techniques for tunnels in karst region,the microseismic monitoring and early warning techniques for rockbursts in deep and long tunnels are presented.For rock engineering and technology inmining engineering,the innovative techniques for roadway support inmines,the simultaneous extraction technique of pillarless coal and gas in coal seams with low permeability,the safe and efficient deep openmining technology,advances in monitoring,early warning and treatment ofmine dynamic disasters are discussed.In addition,the new anchorage techniques and precision blasting technique in rock engineering are introduced.

Research on Delay Risks of EPC Hydropower Construction Projects in Vietnam

In recent years, in Vietnam, economy has been developing rapidly. To ensure rapid and sustainable economic growth, strong support from the energy sector is required. Governments in Vietnam have invested in numerous hydropower projects, many of which employ the EPC (Engineering, Procurement and Construction) contract. However, the EPC general contractors are facing many difficulties, resulting in schedule delays and considerable losses. This research is conducted to highlight the main risk factors in the delays of hydropower construction projects in Vietnam. The research employs the method of statistical calculations and risk analysis to obtain feedback from experts participating in similar projects. The research outcomes are as follows: identifying the risks that can cause delays in EPC hydroelectric construction projects in Vietnam;calculating and classifying the degree of impact of each risk to the progress of the construction. The practical significance of this study is to ensure the timely completion of projects, benefits for the investors, and the EPC general contractors.

Free-Interface Dual-Compatibility Modal Synthesis Substructure Method in Large-Scale Structures

Free-interface dual-compatibility modal synthesis method(compatibility of both force and displacement on interfaces)is introduced to large-scale civil engineering structure to enhance computation efficiency. The basic equations of the method are first set up, and then the mode cut-off principle and the dividing principle are proposed. MATLAB is used for simulation in different frame structures. The simulation results demonstrate the applicability of this substructure method to civil engineering structures and the correctness of the proposed mode cut-off principle. Studies are also conducted on how to divide the whole structure for better computation efficiency while maintaining better precision. It is observed that the geometry and material properties should be considered, and the synthesis results would be more precise when the inflection points of the mode shapes are taken into consideration. Furthermore, the simulation performed on a large-scale high-rise connected structure further proves the feasibility and efficiency of this modal synthesis method compared with the traditional global method. It is also concluded from the simulation results that the fewer number of DOFs in each substructure will result in better computation efficiency, but too many substructures will be time-consuming due to the tedious synthesis procedures. Moreover, the substructures with free interface will introduce errors and reduce the precision dramatically, which should be avoided.

Practice and experience of engineering culture development in the Sutong Bridge project

To keep up with the time,culture is integrated to large-scale construction project management in China,which will absolutely add more vitality into construction project management in our country.Engineering culture is an integration of project construction and engineering culture.However,engineering culture development enjoys its own particularity as a project is constructed once only within a limited period of time.This paper gives affirmative opinion that engineering culture development in large-scale projects backs project management on the basis of thorough investigation of engineering culture development in Sutong Bridge Project and after deepened analysis,proposes new thinking pattern of engineering culture development in large-scale projects in a systematic manner,including thorough understanding of the essence of engineering culture,principle and contents of engineering culture development as well as efficient method in respect of establishment and implementation of engineering culture,and therefore provides a standard reference and systematic thinking pattern for engineering culture development in future large-scale projects.

The Application of 3D Visualization Technology in the Construction of Water Conservancy and Hydropower

This paper put forward the structure and construction process of three-dimensional visualization of hydroelectric construction system model based on GIS and 3D visualization platform. The paper first describes the 3D visualization based on GIS, then discusses the method of constructing 3D visual digital model, and then introduces the terrain digital technology, feature modeling technology. Finally, the technical route shows that this method has good practicability.

数字孪生水利水电工程扩展数据结构建立方法

针对水利水电工程专业众多,建模工具的差异会导致专业协同或阶段性成果移交时出现数据移交难度大甚至数据丢失的问题,创新性地提出通过按需扩展IFC(工业基础类)原数据结构,建立数字孪生水利水电工程扩展数据结构方法,形成面向语义表达、几何表达和属性集表达的水利水电工程IFC扩展表达方式,为水利水电工程易丢失的数据提供标准化存储空间。以此为基础,基于Autodesk Revit软件并借助Revit IFC Exporter开源工具包,研发包含几何信息、属性信息等的扩展IFC导出功能,对坝体结构进行扩展和导出,验证扩展数据结构建立方法的可操作性。最终通过数据移交案例,证明了该方法能够有效保证工程信息在移交过程中不丢失。

横断山区水电工程扰动灾害及风险分析

水电作为全球公认的清洁能源,但水电站的大量建设会人为的改变流域水文条件,对流域内地质环境的影响也仍未可知,因此亟需查明水电工程与地质环境之间的互馈作用。以我国水电工程密集区——横断山区作为研究区,首次对横断山区内的水电工程及扰动灾害进行系统的研究,通过遥感解译及现场验证,获得金沙江、澜沧江、岷江、雅砻江、大渡河以及怒江6个流域内的水电工程共计162座,水电工程扰动灾害共计2841处,并对灾害空间分布规律进行分析。结合前人研究和团队最新成果,对水库水位抬升及循环涨落作用下的库水作用,水库滑坡特征开展分析,揭示了水库滑坡失稳原因。在此基础上提出了水电工程扰动灾害风险分析方法,对6个流域分别开展风险评价,获得了各个流域在不同规模灾害下的经济及人口风险分区图。本研究可为横断山区及其周边区域未来水电开发提供指导,这对保障区域工程的安全建设具有重要意义。

力学在水利水电工程专业课程中的融会贯通——以水工建筑物课程为例

力学课程是水利水电工程专业的基础课程,在整个专业培养教育中起着承上启下的重要作用。以水工建筑物课程为例,总结了材料力学、水力学、土力学等多门力学知识在专业课程中的具体应用;指出力学课程与专业课程的教学应紧密结合,即力学课程的教学应结合专业背景,从传统的“理论模式”向“工程模式”转变,专业课程的教学应从基本的力学原理出发,加深学生对工程问题的理解。

基于BIM与GIS的水利水电工程开发设计应用研究

为了解决水利水电项目建设中任务量大、专业技能多、操作难度高、环境干扰严重的问题,往往要进行多次论证和优化工程步骤,保证施工质量。采用BIM(Building Information Modeling)+GIS(Geographic Information System)技术对水利建筑模型进行优化,并对建筑进行外观设计,为模型的搭建提供坚实基础。结果表明,在水利水电项目建设过程中,以BIM+GIS技术模型为基础可快速模拟待查找的工程进度,有利于管控工程资金和监督工程实施进度,可以大幅度提升水利项目的信息化程度。

水利水电工程移民社会融合状态全过程评估理论初探

作为水利水电工程建设大国,中国水利水电企业“走出去”仍然面临相对滞后的水电标准问题。从推动“一带一路”倡议、构建中国话语权和提升中国现代化程度的角度出发,初步构建水利水电工程移民社会融合状态全过程评估理论,并就总体框架、过程评估与结果评估进行了阐释。在过程评估上区分为规划期、安置期和后期扶助期;在结果评估上分为环境适应、人口发展、文化融合3个方面。以三峡工程为案例,初步检验了全过程评估理论的科学性、合理性与可行性。未来有关工程移民的研究还应拓展全过程评估的应用范围,进一步对社会重构问题给予足够的关注,并着力构建具有中国特色的评估体系。

水电工程主厂房防火防烟分区划分的探讨

鉴于《水电工程设计防火规范》修编过程中,对主厂房防火分区、防烟分区和疏散距离存在不同认识,本文从防火设计的基本理念出发,分析了水电工程的特殊性,同时采用性能化设计数模理论,确定了规范中防火分区、防烟分区面积,以及疏散通道长度的依据,探讨了水电工程的特点,为特殊工程防火设计规范编制提供参考。