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1.
Scientists advise limiting global warming to 1.5°C with substantial actions by 2030. Our viewpoint argues that climate response strategies in Canada have underemphasized and underestimated the potential contribution deep energy retrofits can make to greenhouse gas (GHG) emissions reductions, leading to inadequate responses in the building sector, and that Canada can (and should) be ambitious with building retrofits over the next decade. GHG savings from building retrofits can be realized more quickly than GHG reductions from other sectors, and either deliver net cost savings or are cost‐effective when compared to other mitigation measures. Retrofits can also provide social and economic benefits, such as improved health and comfort, and lower energy costs. This paper reviews energy use and building retrofits in Canada and argues the following should be implemented: (1) focus innovation on deep energy retrofit processes, not singular retrofit actions; (2) maximize both social and environmental benefits; (3) improve data gathering and availability for analysis and delivery; (4) innovate for a process of decisions and to avoid “dropouts” during the retrofit process; and (5) focus innovation on business models that maximize benefits.  相似文献   
2.
Tie-rods are essential structural elements, which have been employed for centuries in masonry historical buildings, either during the construction or in successive strengthening interventions, with the aim of containing dangerous horizontal actions. The actual work conditions of these tie-rods, which are strongly influenced by their load history, are difficult to be quantified theoretically, and an effective method for their measure is of great importance in order to ensure the efficiency of these elements during the time and the stability of the entire building. Common measurements are often carried out adopting models based upon significant simplifications, like, for example, hinges at the extremities. These assumptions, rarely represent the real work conditions for anchorages. In this work, a non-destructive testing method is presented, based upon sophisticated dynamical models that can take into consideration many of the circumstances neglected by the simplified models. Four case studies are extensively described, trying to embrace the most common situations in term of peculiar features of the building, structural configuration, and load history. The discussion of the results yields the safety margin of the rod with respect to the material failure and provides important indications about the overall stability of the whole building.  相似文献   
3.
A framework for quick seismic assessment and retrofit of traditional unreinforced masonry (URM) structures is presented. The proposed methods build on simple principles of structural dynamics and are used as an alternative to detailed time-history analysis, in recognition of the prevailing need for simple and practical methods, compatible with the low-budget and the limited level of knowledge regarding materials, internal force paths, connectivity and condition of older URM structures. An objective is to identify areas in the building that are particularly susceptible to damage and for guiding the types of the required global interventions to improve seismic response. Demand and supply are expressed in terms of relative drift ratios that quantify the intensity of out-of-plane differential translation and in-plane shear distortion of masonry walls. A characteristic traditional building type of timber-laced masonry is used as a model structure for illustration of concepts. The morphology and geometry of the building correspond to a statistical sample of the actual traditional unreinforced masonry buildings (TURM) found in historical centers of many towns in the greater region of Northern Greece. The methodology is particularly useful for setting retrofit priorities and management of the collective seismic risk of historical entities.  相似文献   
4.
康熙、雍正、乾隆以及嘉庆朝所建的宫殿,在传统礼制规定内,其宫殿环境、建筑布局及艺术等力求贴近现实生活。表现出创造惬意的环境和方便舒适的建筑、满足皇帝的理政及生活要求等一系列特性。这也构成了“乾隆时期”宫殿建筑的整体风格。  相似文献   
5.
本文介绍了清代宫廷建筑的管理机构与官员状况、宫廷建筑工程的各项管理制度,并列举了内阁、军机处、宫中、内务府、工部等处的部分档案,这些档案内容涉及紫禁城宫殿楼阁、苑囿行宫、陵寝、坛庙寺观、盛京皇宫及与宫殿建筑有关的河道、沟渠、园林、道路等的兴建和维修状况。这些清代档案是我们现今研究清代宫廷建筑的第一手资料,也是我们保护维修现存宫殿建筑的可靠依据,有着重要的史料价值。  相似文献   
6.
Anatolian Seljuks, a territorially-powerful medieval government, held their fleet at bases on the Black Sea and Mediterranean coasts, and constructed permanent stone buildings to protect their navy. Although most of these buildings have disappeared, 13th-century defended shipyard buildings have survived at Alanya, on the Mediterranean coast of Turkey. These buildings are not only important architecturally, but can give clues to the types of warships used by the Anatolian Seljuk navy, of which little is known. The dimensions of the shipsheds help us to analyse the construction of these naval vessels.
© 2009 The Author  相似文献   
7.
Abstract

In view of the compendium of field evidence and supporting analysis work indicating the possible damaging effects of vertical earthquake ground motion, this paper addresses the problem of code-type vertical force calculation. In light of recent engineering seismology studies of the relationship between vertical and horizontal peak ground acceleration, the inadequacy of the 2/3-rule depicted by codes is highlighted. A simple piece-wise linear relationship is proposed and shown to represent existing strong-motion measurements adequately. Bilinear and inelastic spectra are derived and studied. It is demonstrated that net tensile forces and displacements may ensue, thus eroding the shear resistance of RC columns. A simple procedure is outlined whereby modal analysis may be employed to estimate conservatively vertical earthquake forces on buildings. Finally, areas of further exploration and refinement are identified.  相似文献   
8.
A procedure for deformation-controlled, or displacement-based, seismic design of multistorey RC buildings is proposed, implemented and applied for the full design of a four-storey RC structure. It is integrated into the overall structural design, along with the design for the non-seismic actions and consists of a ULS verification against the conventional strain limits for a frequent “serviceability” earthquake and of proportioning the compression reinforcement and the transverse reinforcement of critical regions of members to meet the member peak inelastic chord rotation demands under the “life-safety” seismic action. Quantitative rules and expressions are proposed for the estimation of (a) mean and upper-characteristic peak inelastic chord rotation demands, through appropriate linear-elastic analyses, and (b) mean and lower-characteristic values of member ultimate chord rotations, in terms of member geometric and material data.  相似文献   
9.
The townscape of “old” Lerwick reflects its traditional focus on the sea for its economic base. The major elements in this cohesive visual character are the closely clustered houses in the steep hillside district of the Lanes, the narrow, winding principal commercial street, and the lodberries projecting out into the harbour. The latter were constructed to meet the needs of the prosperous expanding trade period of the latter half of the 18th century and first half of the 19th century. Harbour improvements in the final quarter‐century of the 1800s ended their commercial usefulness. After a century of declining use and of neglect they are being restored as part of the renewal of “old town” Lerwick.  相似文献   
10.
Much fuss has been made of the “spatial turn” in recent years, across a range of disciplines. It is hard to know if the attention has been warranted. A confusion of terms has been used—such as space, place, spatiality, location—and each has signified a cluster of often contradictory and confusing meanings. This phenomenon is common to a range of disciplines in the humanities. This means, first, that it is not always easy to recognize what (if anything) is being discussed under the rubric of space, and second, that over‐extended uses of the cultural turn have stymied meaningful engagement with (or even a language of) materiality in discussions of space. This article shows how materiality has been marginalized both by a casual vocabulary and a vigorous a priori epistemological holism on the part of scholars, and how the spatial turn has been too closely linked to the cultural turn to allow it to develop its fullest explanatory potential. It demonstrates how historians might profitably theorize the significance of place and space in their work (borrowing techniques from geographers and anthropologists, and referring to the phenomenological tradition), and sets out some challenges for using space more effectively in explanatory systems. Inspired by environmental history, sociology, and science and technology studies, I propose a way of establishing space as different from conventional historical handling of materiality, and end by identifying some methodological problems that need to be solved if we are to proceed on a surer footing.  相似文献   
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