SEISMIC AMPLIFICATION AT A SOFT SOIL SITE WITH LIQUEFIABLE LAYER

It is well known that local soil conditions play a key role in the amplification of earthquake waves. In particular, a liquefiable shallow soil layer may produce a significant influence on ground motion during strong earthquakes. In this paper, the response of a liquefiable site during the 1995 Kobe earthquake is studied using vertical array records, with particular attention on the effects of nonlinear soil behaviour and liquefaction on the ground motion. Variations of the characteristics of the recorded ground motions are analysed using the spectral ratio technique, and the nonlinearity occurring in the shallow liquefied layer during earthquake is identified. A fully coupled, inelastic finite element analysis of the response of the array site is performed. The calculated stress-strain histories of soils and excess pore water pressures at different depths are presented, and their relations to the characteristics of the ground motions are addressed.     

Analysis of the Effect of Provisional Ties on the Construction and Current Deformation of Mallorca Cathedral

This article presents the analysis of the structure of Mallorca Cathedral taking into account the influence on the structural behavior of auxiliary iron ties used during the construction process. Recent studies (Roca et al. 2012, 2013) presented some hypotheses about the construction process of the cathedral. This article complements the previous results by considering the use of auxiliary ties as temporary stabilizing device during the construction. Evidence of the use of ties during the construction has been recognized after a comprehensive survey. The study of the role of such ties and the effect of their later removal are studied by a FE analysis carried out on a representative bay of the structure. The study includes a time-dependent FE analysis after the removal of the ties to assess the long-term structural behavior. The results of the numerical analysis are compared with the deformation trends identified by means of a recent monitoring campaign.     

复杂理论视角下城市健康地理学探析

城市公共健康问题是根植于所依托的地域空间背景下的复杂问题,因而,目前学界主要以还原论的模型假设来分析影响城市健康的复杂多因子关系时存在一定局限。本文在分析城市健康地理问题的"地方"复杂性基础上,提出用复杂理论认识城市的健康问题,将城市健康地理系统看作为具有开放性、组分的知识局限性、自组织性、路径依赖、涌现性、正反馈和锁定特征的复杂系统。从复杂理论视角探讨了当前城市健康地理学研究的三个主要议题,进而提出复杂理论视角下城市健康地理学研究框架及未来研究展望。