Testing a Retrofit Concept to Prevent Progessive Collapse

测试防止逐渐倒塌的改造概念

• 批准号: 0135418
• 负责人: Abolhassan Astaneh-Asl
• 金额: $ 3万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-15 至 2002-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0135418&HistoricalAwards=false
• 关键词: Testing; Retrofit; Concept; Prevent; Progessive

During extreme events such as earthquakes and explosions, it is quite possible that a critical element of a building structure, such as a column, collapses. When a column in a building collapses the columns above this column, not being supported anymore, can collapse resulting in a catastrophic and "progressive collapse" of all floors above. Such a progressive collapse can result in tragic loss of many lives such as the 1995 Murrah Building tragedy in Oklahoma City. In order to avoid such tragedies, the structure should have mechanisms that loss of one column does not result in a "domino" effect and progressive collapse of columns above or a large portion of the structure. Dr. Astaneh has just completed successful testing of a steel cable-based mechanism to prevent such progressive collapses. In the system, steel cables are placed inside the floor slabs and when a column is removed, the cables act in a "catenary" action similar to a suspension bridge cable and prevent collapse of the floor and progressive collapse of the structure. The tests just completed have been for new construction where it is possible to place the steel cables inside the floor slabs. Realizing the success of this system in preventing collapse of new buildings, we are proposing to test the system as a measure of retrofit for existing vulnerable buildings. Fortunately, we have the specimen from the just completed tests in a state of minor damage and plan to use the specimen one more time for this proposed exploratory investigation.The main objective of this Small Grant for Exploratory Research is to take the existing specimen which is a one story 60ft by 20 feet building and add the cable-based system to it (under the existing slab) as a measure of retrofit and explore potential of this system in preventing progressive collapse of the existing building structures.

在地震和爆炸等极端事件中，建筑结构的关键元件（如柱子）很可能会倒塌。当建筑物中的柱倒塌时，该柱上方的柱不再被支撑，可能会倒塌，导致上面所有楼层的灾难性和“渐进式倒塌”。这种渐进式倒塌可能导致许多人丧生，例如1995年发生在俄克拉荷马州市的默拉大厦悲剧。 为了避免此类悲剧，结构应该具有这样的机制，即失去一根柱子不会导致“多米诺骨牌”效应和上面的柱子或结构的大部分逐渐倒塌。 Astaneh博士刚刚完成了对一种基于钢索的机制的成功测试，以防止这种渐进式倒塌。在该系统中，钢索被放置在楼板内，当柱被移除时，钢索以类似于悬索桥缆索的“悬链线”动作起作用，并防止楼板倒塌和结构的连续倒塌。刚刚完成的测试是针对新建筑的，在新建筑中，可以将钢索放置在楼板内。由于该系统在防止新建筑物倒塌方面取得成功，我们建议测试该系统，作为现有脆弱建筑物的改造措施。幸运的是，我们刚完成的测试中的样本处于轻微损坏状态，并计划再次使用样本进行这项拟议的探索性研究。这项探索性研究小额赠款的主要目标是采用现有的样本，这是一个60英尺乘20英尺的单层建筑，并将电缆系统添加到其中（在现有楼板下）作为一项翻新措施，并探讨该系统在防止现有楼宇结构连续倒塌方面的潜力。