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991.
G. Zhang 《Construction Management & Economics》2013,31(5):529-543
Raised floor systems (RFS) were initially developed for computer room applications. As an alternative for general office space fitout, they have not been widely accepted, particularly in Australia. Despite the potential exhibited, such as improved ventilation and air quality when used with underfloor sub‐systems, and the flexibility for office space reconfiguration, RFS implementation had encountered problems, ranging from the excessive costs perceived by owners and developers, to the lack of technical expertise among builders and contractors on the installation of RFS and specialized components. In the research work reported in this article, these problems were identified together with the highlighting of 44 Significant Influence Factors (SIFs). This was achieved through RFS product study, questionnaire survey, interviews and site observations. These SIFs and problems were then amplified in the research by industry focus groups and life cycle cost comparison between RFS and ceiling based fitout methods. The resulting 36 Project Level Critical Factors (PLCFs) pertaining to fitout design, construction, operation and maintenance were then considered in a constructability study, which established an integrated constructability framework for RFS fitout implementation, the most appropriate contracting strategy, and a process‐based model for RFS product selection under local conditions. A set of guidelines that recommend main activities and subsidiary tasks through five stages of RFS project implementation was also presented. These findings will contribute to improved awareness, adoption rate and implementation efficiency of RFS fitout in the Australian office building industry. 相似文献
992.
Weiguang An Kai Liang Taolin Zhang Xiangwei Yin Yuzhou Cong Yunji Gao Jianwei Cheng 《火与材料》2019,43(8):1003-1009
In this work, cone calorimeter tests were conducted to investigate fire properties of interior materials (floor covering [FC], aluminum plate covered with paint [APCP], light diffuser [LD], and gel coat [GC]) used in low‐floor light‐rail trains. Ignition time (tig) of each material decreases with the increase of radiative heat flux. The decreasing order of the four samples by ignition time under the same radiative heat flux is LD > APCP > FC > GC. The heat release rate (HRR), peak value of HRR (PHRR), time from ignition to PHRR (tp), fire growth rate index (FIGRA), and fire growth index (FGI) rise with the increasing radiative heat flux. For the FC, LD, and GC, single HRR peak is observed in the HRR history while three peaks are observed for APCP. For PHRR, LD > FC > APCP > GC, while for tp, GC < FC < APCP < LD. Under most conditions, the FIGRA and FGI of the FC is the highest among the four materials. Results of this work are beneficial to evaluate fire hazard of low‐floor light‐rail train and determine the emphasis of fire prevention. 相似文献
993.
为了解决乌干达卡鲁玛尾水隧洞底板开挖的石方超挖问题,在底板开挖的初始阶段,进行了一系列光面爆破装药结构改进技术实验,通过调整底板光爆孔孔距、抵抗线、线装药密度,最终确定了合理的底板开挖光面爆破参数:孔距61.8cm,最小抵抗线60cm,装药间隔61.3cm,线装药密度160.4g/m。实验结果表明:光面爆破装药结构改进技术同样适用于隧洞底板开挖,底板光爆孔内按一定间距分布的炸药卷和导爆索在处于自由状态的情况下,仍然能够正常起爆。在卡鲁玛尾水隧洞底板开挖的光面爆破施工中,底板开挖半孔率达90%以上,底板总平均超挖16.67cm,大大减少了石方超挖量,节省了大量回填混凝土,有效降低了开挖成本。 相似文献
994.
Damiano Arena Apostolos Charalampos Tsolakis Stylianos Zikos Stelios Krinidis Chrysovalantou Ziogou Dimosthenis Ioannidis 《国际生产研究杂志》2018,56(8):2855-2877
The industrial domain is experiencing a so-called fourth industrial revolution in which the evergrowing complexity of manufacturing information, the increasing amount of knowledge and the use of web-oriented techniques, represent three crucial factors that are accelerating the growth of complexity of industrial systems. On the other hand, continuous-evolving requirements in industrial environments, due to technology outbreaks and a new global marketplace, have led to an on-going evolution of human resource management through the creation and adoption of alternative business models. In the past decade, semantic models such as ontologies have been proven to be effective for many knowledge-intensive applications, since they provide formal models of domain knowledge that can be exploited in different ways. For all these reasons, an innovative human resource optimisation (HRO) engine is introduced, which employs semantically enhanced information and conditional random field (CRFs) probabilistic models with knowledge derived from industrial shop floor level, and proposes the right person for the right job in real-time shop floor operations towards optimising decisions on how to implement and schedule either repeatedly or non-occurring tasks. Industrial information data flow and semantic enrichment were ensured through the combined use of a common interface data exchange model (CIDEM) and ontologies, after which a feasibility study at a chemical plant presented interesting preliminary results. 相似文献
995.
扁梁空心楼盖体系在高层建筑中的应用较少,相应分析方法还不够成熟。以重庆某高层建筑实际应用为例,研究了空心楼盖面外刚度对整体结构分析的影响。通过对比不同分析方法的楼盖内力,指出扁梁空心楼盖应进行梁板整体分析,并介绍了实用分析方法——拟梁法。 相似文献
996.
Wen‐I Liao Juin‐Fu Chai Chin‐Hsiung Loh Shiang‐He Huang 《The Structural Design of Tall and Special Buildings》2013,22(10):770-782
Damage of expensive equipment installed in the raised floor system of high‐tech fabs was often observed during past earthquakes in Taiwan. This resulted in a huge loss of manufacturing functions and properties for the high‐tech industry. Therefore, there is an urgent need to understand the dynamic characteristics of the raised floor system for future seismic protection. This paper explores the seismic performance of a raised floor system under shake‐table excitations. The raised floor used was a pedestal–stringer frame structure supporting the simulated equipment. This raised floor system was the typical system frequently used in semi‐conductor fabs of Taiwan. The input motions for the shake‐table tests were the waffle‐slab floor accelerations of a typical semi‐conductor fab to simulated ground motions. The ground motions were simulated according to the phase spectrum and the maximum potential earthquake of the site located at Hsin‐Chu Science Park, Taiwan. The dynamic characteristics of the raised floor system were studied and discussed. This study also employed the finite element package to carry out numerical simulation on seismic responses of raised floor systems. Comparison with the experimental data showed that the proposed simulation model achieved excellent performance. Finally, the effectiveness of base isolation for reducing the acceleration of the system was also studied. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
997.
从材料要求,机具设备的选择,基底性能要求,施工过程,成品保护等方面入手,介绍了聚氨酯地面施工质量控制措施,指出在施工过程中必须从各个工序进行严格的质量控制,才能保证质量,满足使用要求。 相似文献
998.
999.
1000.
彩色自流平新型环氧地坪涂料的研究 总被引:6,自引:0,他引:6
研究了用新型TEG 99环氧树脂配制性能优良的彩色自流平新型环氧地坪涂料 ,讨论了活性环氧稀释剂、脂环胺固化剂、填料等各组分对涂料性能的影响。 相似文献