黏弹性薄板蠕变屈曲的载荷-时间特性研究

通过对黏弹性薄板压屈的稳定性分析,着重讨论了蠕变屈曲载荷－时间的特性,理论分析表明：黏弹性薄板蠕变屈曲与材料的力学性能密相关,屈曲载荷不像弹性薄板为一定值,而是与时间相关的;在一定载荷下,经过一段时间后出现延迟屈曲,相关的实验研究也证实这一重要结论;这种延迟失稳问题在工程中有其重要的意义。

TEMPORAL CHARACTERISTICS OF LOADING FOR CREEP BUCKLING OF PLATES

Time-dependent characteristics of buckling load under creep condition are studied by analyzing the stability of viscoelastic plate. A time-dependent function that depends upon the materials behavior in the buckling equation of a plate is derived. Buckling load of the structure is investigated theoretically. The analytical results show that the creep buckling is dependent not only upon the dimensions of structure but also the viscoelastic behavior of material. There exists a "delay buckling" under creep condition. The value of critical load of instability relates to time and depends on the functions of material. Under a given load, instability may occur with a time delay. The tests of thin-plate by means of HDPE (high density polyethylene) were to be done by authors. The experimental results are in good agreement with theoretical analysis.