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排序方式: 共有886条查询结果,搜索用时 15 毫秒
1.
装配式建筑相较于传统建筑,具有节能减排、绿色环保、快速施工、工业化生产和缩短工期等优势,能有效改善我国现阶段建筑业劳动力低、技术创新弱、建筑品质不高的局面,推动建造方式的改变,并能大幅提高企业信息化、可视化管控管理水平,并通过预制装配式产业链的整合,催生相关新产业和服务业,可以使产业链上各企业的核心竞争力得到提高。全产业标准化,规格化,使得信息流、资金流和物流得到有效整合。 相似文献
2.
《International Journal of Hydrogen Energy》2021,46(64):32350-32357
Currently, the United Energy System (UEC) of Russia is trending in the deficit of peak and half-peak capacity with a simultaneous increase in the number of nuclear power plants (NPPs), which will require the participation of the NPPs in the variable part of the schedule of electrical loads.In addition to the economic need to maintain the high-level utilization rate, there are technological limitations of maneuverability for NPPs.The authors developed an approach to solving this problem by combining with an environmentally friendly energy source – an autonomous hydrogen power complex, which includes thermal batteries and an additional multifunctional low-power steam turbine installation.The developed energy complex can also provide reliable reservation of electricity supply to consumers of their own needs of the nuclear power plant in case of complete blackout of the plant.The feasibility study of the main equipment of the autonomous hydrogen power complex, which is necessary for combining with a two-unit nuclear power plant with WWER-1000, has been evaluated.On the basis of the assessment of the inflation indicators of the Russian economy over the past 11 years, three variants of fuel cost dynamics and tariff rates for electricity (capacity) as well as the size of operating costs, including depreciation deductions to the main equipment, are defined, taking into account the current principles of price formation.The result is a value for accumulated net present value, depending on the ratio of the cost of the half-peak and off-peak electricity at different inflation rates.The positive economic effect of reducing the risk of the core damage accident, replacing the construction of the gas turbine unit as a maneuverable source of electricity in the power grid and increasing the income of the Russian federal budget from the savings of natural gas has been taken into account.The greatest economic efficiency is achieved with maximum projected inflation, which is associated with the maximum rate of discounting and the high rate of growth of electricity tariffs.Reducing the risk of the core damage accident ensures that the proposed approach is competitive in all the inflation options under consideration and the ratio of electricity tariffs. 相似文献
3.
Special‐purpose solutions in the fire‐protective evaluation of construction details Very often components or construction details in existing buildings but also in new buildings cannot be evaluated with regard to its fire resistance ability considering established technical building regulations. There are no regulations for the evaluation of such components or construction details as these specific construction details have not been evaluated by a certified test authority. However, these components and construction details very often can be classified in fire resistance classes e. g. by evaluating fire tests, with regard to DIN 4102‐4, on the basis of similar proof of usability or only by pragmatic considerations. Since introducing the technical approval of the fire protection Eurocodes more often engineering methods of fire protection are used based on these Eurocodes by using temperature assessment in order to secure the evaluation results. Within this essay we show methods and ways of fire‐protective evaluation for components and construction details. The approach of proof including dimensions of possible upgrade measurements if necessary are being illustrated by examples of use out of practical experience. At the same time different materials such as steel, concrete and wood will be treated with different fire‐proof products. The essay is to explain ways of evaluation of components and construction details involving fire‐proof requirements including upgrade measurements also especially for existing buildings. 相似文献
4.
Giovanni Fabbrocino Gerardo M. Verderame Gaetano Manfredi Edoardo Cosenza 《Engineering Structures》2004,26(14):463-2148
Structural assessment of existing reinforced concrete constructions under gravity loads and seismic actions has a high social and economical impact; actually in many European countries, most of the buildings dates back to 1960s and 1970s and cannot ensure satisfactory seismic response, since many areas have been later classified as seismic or since design has been carried out according to obsolete codes. These structures are generally reinforced with smooth bars that exhibit poor bond and need specific anchoring end details. In the present paper, some key aspects of structural models of smooth reinforcement for old-type r.c. frame analysis are reported. Results of experimental tests on smooth reinforcement and circular hook anchoring devices are also used to discuss some aspects of behavioural models of beam to column critical regions. 相似文献
5.
整体的完善——建筑细部设计谈 总被引:1,自引:0,他引:1
从建筑细部概念入手,阐述其基本定义、分类,制定出设计中应遵循的整体性原则,最终致力于具体的细部设计方法的探讨。 相似文献
6.
根据《建筑抗震设计规范》(GBJ11-89)要求,对7~9度时的钢筋混凝土框架结构在进行罕遇地震作用下的薄弱层弹塑性变形验算时,需要确定楼层受剪承载力,但按照常用的计算方法计算时,工作量大,且较繁琐。笔者对常用的“拟弱柱化法”的计算公式进行简化,提出了实用计算公式,使计算更简单,工作量大大减少,而且误差很小,方便了设计使用。 相似文献
7.
对北京应用物理及计算数学研究所信息楼的建筑方案进行了总结分析,阐述了它在与规划的协调、功能、造型、细部设计等方面的设计特点,也指出了一些存在的问题。 相似文献
8.
线型旅游空间研究——以京杭大运河为例 总被引:5,自引:0,他引:5
在旅游地空间结构和相关"线"状空间研究的基础上,借鉴在世界遗产保护领域的先进理念"文化线路",提出"线型旅游空间"概念,界定为基于遗产保护进行旅游开发的旅游地空间类型.以京杭大运河为例,将其空间特征总结为历史悠久、跨越区域、文化多元和产品趋同等4个主要方面,并在此基础上提出了对大运河旅游规划的启示,应树立保护为先的理念,在全局的视角下避免目前的旅游形象和旅游产品趋同的现象,进行多角度的差异性定位;同时,基于大运河的大尺度、跨区域性,提出建立相应机构加强协调管理,并进行流域联合营销和区域联合营销. 相似文献
9.
10.
光照重力坝坝基断层影响及处理的三维数值模拟 总被引:5,自引:0,他引:5
200m级光照重力坝坝踵和坝趾分别存在较大规模的断层,为了分析和评价断层对重力坝应力位移和坝基稳定性的影响,以及建坝后由于围压变化导致的断层变形模量提高对坝体的影响,对重力坝典型坝段和坝基岩体的联合作用进行三维数值模拟。对两条断层分别进行浮值分析,用强度储备系数法计算受断层影响的坝基安全稳定性,并分别模拟对两条断层进行的不同方式加固处理措施进行模拟。研究结果表明,位于坝趾的F2断层对坝体应力位移状态影响较大,也是坝基稳定性的控制性因素之一,在进行固结灌浆处理提高强度后,不仅可以提高坝基稳定性,而且可使坝体应力状态得到改善。位于坝踵的F1断层开挖并回填混凝土处理不宜过深。同时,建坝后围压变化导致断层变形模量的提高对于坝体应力控制是有利的。 相似文献