摘要
高空坠物落点研究对建筑高空坠物的安全防护设计具有意义,目前的研究主要偏重于统计和经验。基于高空坠物的物理过程,考虑空气阻力的影响,提出了高空坠物落点理论模型;基于高空物体意外踢落过程中的能量转换,提出了高空物体意外踢落后水平初始速度计算的理论公式;根据施工现场坠落物的特点,基于高空坠物落点理论模型,计算了施工现场高空坠物散落半径,给出了施工现场地面安全防护水平宽度。
The aim of this paper is to set up a theoretical model for the drop points of the falling objects in hoping to make it suitable for the design practice to increase the possibility and the ground protective safety sphere. For the said purpose, we have first of all made an exploration of the effects of the air resistance on the movement of the falling objects both in the theoretical and practical meaning. As is known, in accordance with the Newtoni- an Second Law, two differential equations of motion for the falling objects are to be involved under a certain initial velocity respec- tively developed with the zero and non-zero horizontal velocities of falling objects when falling. And, accordingly, we have put for- ward the following concepts, such as the initial horizontal velocity （%） , their weight（m） , the coefficient of the air resistance（k） , and the falling height（h） so as to represent the horizontal space of the falling bodies. Based on the theorem of moment of the mo- mentum and the energy conservation law, it is possible for us to deduce the initial horizontal velocity of a falling object under the assumption that it is likely to hlt a person who passes by. Further- mare, we can also work out the initial horizontal velocity of the falling body and the sphere of the ground safety protective frame- work of the construction site in accordance with the formula of the horizontal space of the drop point of the falling object. The main results of this paper can be summarized as follows ： （ 1 ） The hori- zontal distance of the drop of a falling object ought to be propor- tional to the initial horizontal velocity, whereas negatively related to the coefficient of the air resistance ; （ 2 ） It is inversely propor- tional to the mass or weight of the falling object; （3）Thus, due to the presence of the air resistance, the falling object tends to prolong its falling velocity first, and, then, to decrease with the increase of the falling height. Thus, the product of the initial horizontal velocity of the falling object （ Unit ： m/s ） and its mass or weight（Unit： kg）would be made equal to about 2.5. The study results can therefore be expected to be beneficial for improving the construction engineering safety. Besides, due to the presence of the air resistance, the falling body tends to increase its speed of falling at first, and then begins to decrease with the increase of the falling height. And, so, it can be seen that the product of its initial horizontal velocity （ Unit ： m/s ） and its weight （ Unit ： kg ） should be about 2.5. From what is said above it can be concluded that the study results we have gained should be beneficial for improving the construction protective safety.
作者
刘立平
廖东峰
李英民
何向东
LIU Li-ping LIAO Dong-feng LI Ying-min HE Xiang-dong(Key Laboratory of New Technology for Construction of Cities in Mountain Area （ Chongqing University）, Ministry of Education, Chongqing 400045, China School of Civil Engineering, Chongqing University, Chongqing 400045, China Chongqing Second Construction Co. , Ltd. , Chongqing 400030, China)
出处
《安全与环境学报》
CAS
CSCD
北大核心
2016年第6期141-144,共4页
Journal of Safety and Environment
基金
中央高校基本科研业务费项目(106112015CDJXY200005)
重庆市建设科技计划项目(2009-No6
2011-No2-85)
关键词
安全工程
高空坠物
高处作业
施工安全
空气阻力
safety engineering
falling object
high-place operation
construction safety
air resistance
