The Origin,Development and Decline of Back-to-Back Houses in Leeds, 1787–1937

This paper traces the development of back-to-back house building in Leeds. It first outlines the origin of the house type, before examining the urban layout, building form and social aspects of back-to-back courts in the first half of the 19th century, and the role of speculative developers, building societies and sanitary reformers. The focus then turns to the bills, acts and by-laws of the later 19th and early 20th century, and the determination of the people of Leeds to retain their preferred house type. Together, these brought improvements to the design and facilities, culminating in a house type that was far superior to that which was condemned by the back-to-back critics, and arguably had overcome all of the criticisms by the time construction of back-to-backs was prohibited in 1909.     

Fast Nonlinear Analysis of Traditional Chinese Timber-Frame Building with Dou-Gon

ABSTRACT

This article presents a study of the applicability of fast nonlinear analytical (FNA) models in predicting the global response of Chinese traditional timber-frame building with Dou-Gon under seismic excitation. Efforts are made to overcome challenges in establishing simplified calculation models, and the corresponding dynamic equations are derived considering the mechanical behavior of sliding column root, mortise-tenon joint and Dou-Gon (bracket sets). Furthermore, nonlinear time-history analysis is conducted under different seismic excitations. Through a verification study, a good correspondence is obtained with previous shake-table test results. Seismic response analysis is also conducted to investigate the energy dissipation of column root sliding, mortise-tenon joint, and Dou-Gon. Subsequently, peak responses of column root and roof under increased values of peak ground acceleration (PGA) are also analyzed. And then, seismic isolation ability and damping characteristics of the model are discussed.     

Assessment Techniques for Studying the Effects of Fire on Stone Materials: A Literature Review

ABSTRACT

Fire is one of the most severe threats to stone applied in civil engineering and architecture. In most cases, its effects are irreversible and have long-lasting repercussions. In addition to aesthetic alterations, fire can also induce important mineral-chemical, physical, and mechanical changes in stone. Research concerning the effects of fire on stone materials in recent decades has been providing valuable knowledge to inform present and future conservation and restoration actions. In this literature review, the properties and techniques used for studying the effects of fire on stone materials are appraised, summarized, and compiled. A comprehensive and practical overview of those effects is also given. Open porosity and P-wave ultrasonic velocity are the physical and mechanical properties that have been studied most. Other frequently researched areas include chemical-mineralogical changes, color, density, water absorption, uniaxial compressive strength, and modulus of elasticity are also very frequently investigated.     

古建筑振动标准分级探讨

为了对城市古建进行微振动控制,尤其是对交通振动的控制,本工作总结了国内外古建筑振动控制标准,提出了古建筑微振动控制的基本前提和考虑因素.分析了《古建筑防工业振动技术规范》中存在的问题.基于既有国标研究成果,提出了一种考虑古建筑维修历史、保护现状的振动控制标准降级方法,并汇总形成了适用于城市古建筑的微振动控制矩阵.