南京包山式城墙典型病害及整体坍塌预警分析

南京城墙作为现存的世界第一城垣，对其安全性进行科学评估尤为重要。包山式城墙为南京城墙的主要形式之一，由于其与土体相连，受力特点不同于常规的自承重城墙。本研究整理了包山式城墙的6种典型病害，并提出了包山式城墙的数值建模方法，将其简化为城墙-粘结界面-土体的模型。利用ABAQUS软件，结合工程实例模拟土坡强度折减后包山式城墙的鼓胀。研究结果表明：随着土体的强度下降，包山式城墙的位移不断增大形成鼓胀现象，最终发生倾覆坍塌，可通过墙体底部拉应力-顶点位移曲线中的明显拐点确立监测变形预警值；在此基础上，讨论土坡高度对整体坍塌的影响，并给出放坡角度的合理取值；城墙底部的积水浸泡会导致底部强度折减进而发生相对错动，可通过底部墙体达到极限抗拉强度时的最大相对位移确立监测变形预警值。最后，提出了包山式城墙的修缮保护建议。     

基于精明发展的城市扩张与土地利用效益的耦合研究——以济南市主城区为例

精明发展已成为国际化城市发展的主流。在精明发展理论的指导下，以区域中心城市济南为例，选取城市扩张与土地利用效益两个子系统，从空间形态、发展效率、外部影响、用地结构、人口变化、经济规模、公共服务和综合建设八个维度，测度济南市主城区城市扩张与土地利用效益的耦合协调关系。结果表明：①济南市城市扩张阶段性特征明显，扩张模式从单核心向多核心转变；②济南市土地利用效益总体水平较低，但其发展符合“低速-高速-平稳”的变化过程，且近年来呈持续优化趋势；③济南市城市扩张与土地利用效益不符合精明发展要求，城市扩张对土地利用效益的促进作用不足，二者间耦合协调度不高。     

Judging government economic performance

ABSTRACT

The macroeconomic theory of judging contends that when justices on courts of last resort consider cases involving their governments and economic issues their voting behaviour will be affected by the state of the economy. Using decisions from the High Court of Australia from 1970 through 2018, the findings suggest that both economic conditions, particularly inflation and the GDP growth rate, and the partisan identity of the Commonwealth government affect the Commonwealth’s probability of winning economic cases. The High Court’s behaviour is consistent with an institution that is part of the national policymaking system and is responsive to the state of the economy.     

Securing the heights: The vertical dimension of the Siachen conflict between India and Pakistan in the Eastern Karakoram

The Siachen conflict between India and Pakistan is often referred to as the coldest war, or, the endless war atop the roof of the world. The high altitude and extreme climate create a hostile environment that has caused by far the most casualties and imposed tremendous costs on both sides. This environmental setting is usually only cited to underline the absurdity of this more than 30 year old conflict. We, however, argue that rather than being a constraint upon the conflict, the terrain itself is central to the genesis and continuation of the conflict. Further, the vertical dimension is the focus of contestation and the site where mountaineering practices, cartographic imagination and military logic intersect. The inaccessibility imposed by the terrain also implies that far from being a frozen conflict there is a temporal dynamism, as improvements in technology and logistics alter the possibility of maintaining the status quo.