摘要
混凝土坝温度变形呈周期性变化,其相位滞后于气温,该现象通常被解释为由于混凝土导热系数小、热传导慢而引起,但该解释并不全面。本文运用热学与力学基本理论,推导了计算悬臂梁及拱圈温度变形滞后时间的解析公式,并据此研究坝型对滞后的影响,得到以下结论:坝内平均温度的滞后时间大于温度梯度的滞后时间;坝型对滞后时间有较大影响,拱坝水平位移的滞后时间比重力坝要长。
The thermal deformation of a concrete dam changes periodically; and its phase lags behind the air temperature. This phenomenon is often interpreted as due to the low velocity of heat conduction in concrete,but this interpretation is not comprehensive. Based on the fundamental theories of thermal mechanics,firstly this paper derives the analytical solutions for the computation of hysteresis tim e of thermal deformation for cantilever beam and arch rin g,and then applies them to study how the factors including dam type,reservoir water temperature and spatial position affect the hysteresis time. The following conclusions are obtained : the hysteresis time of the mean temperature is greater than that of the temperature gradient; the dam type has a great impact on the hysteresis time,and the hysteresis time of the horizontal displacement of an arch dam is longer than that of a gravity dam.
出处
《水电自动化与大坝监测》
2015年第6期9-12,69,共5页
HYDROPOWER AUTOMATION AND DAM MONITORING
基金
中央高校基本科研业务费(B1020083)资助项目
国家自然科学基金重点项目(51139001)
河海大学水文水资源与水利工程科学国家重点实验室专项基金(20095860120)
关键词
混凝土坝
滞后
温度
解析解
concrete dam
displacement
hysteresis
temperature
analytic solution
