Improving the power generation efficiency of coal-fired units is an effective measure to achieve energy conservation and carbon reduction. The engineering application of 700 ℃ ultra-supercritical coal-fired power generation is hindered by the high price of superalloy materials; therefore, it is necessary to explore new layouts and structures to shorten the high-temperature steam pipelines and reduce the engineering costs. By taking the phase III expansion project—the world's first demonstration project of high-level layout—of the Jinjie coal-fired power plant as an example, this study introduces the engineering innovation practice of the high-level layout technology for an air-cooled ultra-supercritical steam-turbine generator unit. The results indicate that the reinforced concrete frame and shear wall structure can effectively lower the overall center of gravity and improve the seismic performance of the main power house, thereby ensuring the safety of the main power house structure, high-temperature steam pipelines, and steam turbine generator unit through technological breakthroughs. Compared with those of the conventional layout (its operating floor level being 12.6-17 m), the main steam and reheat steam pipelines of the high-level layout (its operating floor level being 65 m) can save 34.2% and 20.9% of raw materials, respectively; and exhaust steam pipes of the air-cooled island can save 93% of raw materials. Furthermore, the power supply coal consumption can be reduced by 4.5-5.1 g/(kW·h) compared with the design value, and the overall economical efficiency is significantly improved. The monitoring data after operation show that all parameters in the real-time on-line monitoring system of the main power house structure are within the safety threshold, and the plant structure and critical equipment are both in a safe state. Therefore, we propose to promote clean and efficient coal-fired power generation technologies and apply the high-level layout technology to the advanced air-cooled coal-fired power units in northeast, north, and northwest China as these regions are rich in coal but short of water. This can provide practical experience for the construction of economical high-temperature steam pipelines for 700 ℃ ultra-supercritical coal-fired power units.

As the resource space height and unit capacity of wind power are increasing,ultra-high wind power towers are widely studied.A new steel-concrete multicellular composite structures tower suitable for onshore wind power was proposed.Based on the aerodynamic theory of wind turbine system,the finite-element model of a 4.5 MW wind turbine was investigated.Then the influence rules of each factor to dynamic response of structures was analyzed.The results showed that the coupling effect of soil and foundation has almost no effect on frequency and modal damping ratio of the tower system.The frequency of tower,the displacement and acceleration of tower head can meet specification requirements.With the increase of wind velocity,the displacement of tower top decreased significantly,and the acceleration of tower top increased.The damping ratio of tower structure had little effect on the displacement of tower top,and had significantly effect on the acceleration of tower top.The research provides a theoretical basis for wind-tunnel test of tower structure.

以某水电站工程库区型弃渣场为例,根据工程地质勘察、室内试验提供的地层参数,结合弃渣场设计图纸,利用Geo Studio软件,计算库区型弃渣场在正常运用工况和非常运用工况下的稳定性计算结果.根据计算结果,可对该弃渣场的设计和施工提供科学依据,确保弃渣场的使用安全性.

随着经济的发展与社会的进步,迫切需要对地下空间进行开发利用,其对地下工程设计理论,施工方法和施工管理技术提出了更高的要求.在这种情况下,地连墙成为了很多基坑工程项目围护结构的首选,地下连续墙外形特点也从传统的直线形发展成曲线形、圆形等形式.为促进深大基坑的研究,基于西安工程项目,PLAXIS 3D进行了三维条件下的多工况数值模拟.验证了三维有限元软件的可行性,研究了基坑围护结构变形特性与相应墙后水平土压力的变化情况、地连墙内力规律、基坑周边环境影响范围等,提出了圆形超深基坑判定准则.

为研究多排槽式反射镜不同位置处的风荷载特性及其互相干扰,对单个反射镜及多排反射镜进行缩尺为1/40的刚性模型测压试验,试验变量为测压模型的风攻角、风向角以及其在群镜中的位置.首先测得各工况下镜面的风压分布数据,绘制镜面风压系数等值线图和反射镜力系数变化曲线,然后分析了反射镜互相干扰对镜面风荷载的影响.研究表明:中间列首排反射镜所受风荷载最大,其阻力系数是单镜的2倍,中间列其余排反射镜阻力系数为单镜的30％～70％;边缘列首排反射镜阻力系数为单镜的1.88倍,其余各排在单镜的1.20倍以上;建议将镜场分为4类区域分别进行结构设计.

塔式定日镜是塔式太阳能光热发电站中重要的聚光设备,设计时控制荷载为风荷载.通过ANSYS有限元软件建立塔式定日镜结构的有限元模型,经过模态分析可知结构频率分布比较密集,风攻角的改变对定日镜结构的低阶模态影响不大.基于刚性模型测压风洞试验,对塔式定日镜进行风振响应有限元分析,并进行气弹模型测振试验,两者的误差在10％以内.根据有限元分析和气弹模型测振试验的结果可知,影响结构风振的模态主要是前3阶,主檩条端部位置的位移响应最大.结构设计时风振系数建议取为1.57.

为了理清水电站建设区的表土资源量,通过实地调查取样分析项目区表土资源数量,测定表层土壤的理化性质,结合相关规范标准,对项目区表土数量、质量及其养分含量进行评价.结果表明:项目区的表土资源主要集中在耕地,林草地表土分布总体较薄且多为含砾石土层,项目区表土总量满足迹地恢复的覆土量,表土质量基本符合青藏高原区土地复垦林草地质量控制标准.

汽轮发电机组高位布置技术可以缩短电厂高温蒸汽管道,是未来700℃超临界燃煤机组减少镍基合金材料使用的有效途径之一.但是汽轮发电机组高位布置技术在国际上尚无成功经验可参考,特别是汽轮发电机组基础的振动特性、抗震性能等有待深入研究.该文依托2×660MW汽轮发电机组高位布置工程,建立汽轮发电机组基础和主厂房结构的缩尺试验模型,采用三点空间激振、多点空间测量的方法分析了基础台板的自振特性,采用专业软件预测多点扰力共同作用下基础的强迫振动响应,并与数值分析结果和控制标准进行对比.结果表明,结构固有频率分布主要集中在20Hz以内,40Hz以后的高阶固有频率明显减少,这种分布为机组提供了较好的运行环境;在机组启动过程中尽量避开机组的临界转速频率,避开率超过10％;强迫振动下台板基础的扰力点和非扰力点的最大线位移、最大振动速度满足规范限值.通过合理设计台板基础下方的弹簧隔振系统,可较好控制汽轮机基础的振动.研究结果为汽轮发电机组高位布置工程设计提供了依据.

The number of power generation elements in a solar power plant is so huge that a small improvement in construction can result in significant cost savings. Therefore, as a new-type supporting structure for the power generation element, the PHC short pile foundation is being continuously improved. The PHC short pile foundation is formed by pouring concrete into the borehole in which a PHC pipe pile is inserted. The interface between the pile and the concrete is usually smooth. The unbalanced wind loads cause the supporting structures to be subjected to cyclic torsional loads. Therefore, the influences of the pipe pile section on the characteristics of the pile-concrete interface and the torsional response of short pile foundation under static or cyclic torsional loads are considered. Ten groups of full-scale model tests on the PHC short pile foundation with round or flanged pile section under different torsional loads are carried out. The test results show that the shallow interface firstly weakens when the torsional deformation of the PHC short pile foundation meets the stage of nonlinear deformation. Under the cyclic torsional loads, the plastic deformation accumulates and eventually leads to concrete cracking. The flange can increase the joint surface between the precast pile and the concrete, which also can provide occlusion between the interface, so as to restrain the development of the plastic deformation and effectively improve the resistance of short pile foundation to the cyclic torsional loads.

The PHC short pile foundation is a new type of supporting structure for the power generation element of a solar power generation station. It is formed by inserting a PHC pipe pile into a hole of 2-3m deep, followed by pouring concrete into the hole. To explore the working behavior of the PHC short pile foundation, field tests were carried out on the sand foundation under the lateral loading, coupled lateral and torsion loading and cyclic loading, respectively. According to the results of inclination of the column top, the displacement at the ground surface and the bending moment along the foundation, the force and deformation characteristics of the PHC short pile foundation and the influence of torsion were analyzed. The influence of pile cap on the inner force and deformation of foundation were then analyzed based on three-dimensional numerical simulation. The results show that the deformation of PHC short pile foundation can be divided into three phases. Torsional loads accelerate the occurrence of the soil plasticity and reduce the crack resistance of pile. The pile cap can efficiently reduce the mudline displacement with little influence on the pile deformation. Under normal ultimate load, the residual deformation after cyclic load is about 2 times of that under single load. Finally, based on the field tests and numerical simulation, the methods for obtaining the proportionality coefficient of horizontal soil resistance coefficient m and proportionality coefficient of soil shear modulus A(g) under small deformation of the pile top are proposed, as well as the empirical methods for obtaining residual deformation.

本文通过数值模型(数模)研究和分析了直筒锥段型钢结构冷却塔塔筒段流场特点,并探讨了直筒锥段型钢结构冷却塔内阻力计算方法.结合风洞物理模型(物模)试验,定性评价了塔内结构构件对塔筒内阻力的影响.数模计算及物模试验结果表明,冷却塔塔筒段阻力值相对较小,在整个冷却系统中所占比例不大.直筒锥段型钢结构冷却塔阻力计算可沿用双曲线冷却塔的阻力计算方法,塔的总阻力计算时建议增加一项塔筒内阻力.蒙皮内置的直筒锥段型钢结构冷却塔塔筒内阻力可采用本文的速度突变构件局阻计算公式进行估算.蒙皮外置的直筒锥段型钢结构冷却塔塔筒内阻力相对较大,可参考本文研究结论或根据具体项目数模或物模研究结果确定.

[Introduction] “Standard for Design of Solar Power Tower Plant” (GB 51307) is a comprehensive standard for solar power tower plant. The standard provides a principle for the design of related special structures. In order to understand the standard provisions and commentary completely when using “Standard for Design of Solar Power Tower Plant”, the paper aims to explain and parse the relative regulations of the structure parts of the standard. [Method] Combining with the standard stipulation, the background of standard formulation was elaborated from the aspects of general requirements, seismic design, ground and foundation, receiver tower structure and support structure of molten salt pump. The common structural types of receiver tower, foundation type of molten salt pump and foundation type of heliostat at home and abroad were introduced. The special problems such as structural control index and damping ratio of receiver tower were analyzed and discussed for engineering application. [Result] Through the introduction of the standard background and special structural types, as well as the analysis and discussion of special problems, the design and principle requirements of special structures in tower solar power plant are further understood. [Conclusion] It provides a basis for engineering application of “Standard for Design of Solar Power Tower Plant” and gives some suggestions for further research.

煤斗是火力发电厂主厂房中必不可少的构筑物.在比较混凝土煤斗和钢煤斗两种传统结构形式优缺点的基础上,提出了一种装配式混凝土煤斗,现场组装方便,工期短,且经济实用,响应了国家大力发展装配式结构的政策.经过计算比较,配置该新型混凝土煤斗与配置钢煤斗方案的抗震性能相似,远优于配置现浇式混凝土煤斗的方案.

为了评估弃碴场的稳定性,通过实地勘察碴场的现状及堆碴体的物理力学参数,选取堆碴体的典型剖面采用Geo Studio软件进行稳定性评估,分析不同工况条件下堆碴体的边坡及其整体的抗滑稳定性.结果表明:目前堆置状态下的碴场边坡及其整体均处于稳定状态,计算安全系数均大于规范规定的安全系数标准.

建立科学合理的农业水价机制,能够促进农业节水,调整用水结构,促进城乡之间、部门之间的水资源优化配置.以宁县湘乐川灌区及25处小型机井灌区为试点,分析区域内用水情况,农业水价现状及其存在问题,以全成本水价理论为基础估算得到区域内灌区的运行维护成本价及终端全成本价;以亩均产值和亩均净效益为基础测算得到农民水价承受能力粮经作物为0.220元/m3,机井灌区的果树等作物为0.848元/m3.针对宁县实际,制定灌区农业分类水价执行方案.该试点方案的实施可为宁县农业水价的调整提供参考.

In order to study the seismic behavior of bent frame column in vertical frame-bent structure,some representative components of a vertical frame-bent structure were selected as the research objects and the quasi-static test of a 1/5 scaled model and ABAQUS analysis were conducted.The study focused on the failure patterns,hysteretic characteristics,ductility,energy dissipation capacity and inter-story drift ratio of the specimen.On this basis,the seismic performance of bent frame column under different slenderness ratios and axial compression ratios were studied according to numerical simulation.Results show that the main failure mode of the specimen is bending failure,which occurs at the bottom of bent frame column.The horizontal bearing capacity is obviously different under loading in different directions with significant eccentricity.The ductility and energy dissipation capacity reduce significantly with the increase of slenderness ratio and axial compression ratio of bent frame column.It is suggested that the slenderness ratio should be less than 45 and the axial compression ratio should be less than 0.2.

通过对某水电站石料场边坡实地调查和分析,确定料场边坡可进行植被恢复的高程为1275.00 m以下.在4种边坡生态恢复方案(植被混凝土方案、栽植槽方案、垫地平台+植被混凝土方案以及垫地平台+栽植槽方案)比选下,考虑到生物连通性及后期生态恢复的连续性,推荐采用垫地平台与栽植槽结合方案.

To study the story drift angle limitation of bent frame column under strong seismic action, the paper analyzed a vertical framed bent structure of a power plant steam engine room. Firstly, nonlinear finite-element analysis of a framed bent column with different initial angles and axial compressions ratio was made. The analysis results indicated that the story drift angle limitation of 1/40 could give satisfied evaluation of aseismic behavior of the framed bent column safely and economically. And then, the dynamic elastic-plastic analysis under strong seismic action of different characteristic sites for the whole structure was conducted. The aseismic behavior of framed bent column was evaluated using the macroscopic evaluation indexes of story drift angle and the microcosmic evaluation index of material strain. The evaluation results of the story drift angle limitation of 1/40 agreed well with those of the index of material strain.

在简政放权、加强事中事后监管的新要求下,水电工程水土保持监测工作面临新的挑战.传统调查监测、地面监测方法已不能满足新的监测要求,遥感监测、无人机低空航拍、集成通信技术等创新型监测方法越来越受到水行政主管部门的鼓励与肯定.文章系统梳理了水电工程水土保持监测方法及其特点,创新型的监测技术采集的数据精度更高,时效性更强,且成本低.

管网系统布置是自压输水管网设计的关键内容之一,结合苏巴什河灌区工程实际,以沉沙调节池位置、管网是否减压及输水线路选择等为影响因素,进行了方案组合.从工程投资、管道耐压等级、管理难度、安全性等方面进行综合比较,从而确定最优布置方案,为类似工程输水管网优化布置提供参考.