CAJ | 학술논문

针对裂纹的存在将降低梁的刚度的实际情形，首先根据断裂力学理论，引入裂纹梁因裂纹扩展而释放的应变能表达式，然后根据金属材料的特点，运用有限元位移法建立裂纹梁单元的动力学模型，再在梁单元模型的基础上应用有限元位移法建立裂纹梁结构的动力学方程。研究表明：基于有限元位移模式所建立的动力学方程较好地体现了裂纹梁动态性能与其结构参数和裂纹参数之间的内在关系，反映了裂纹的位置及长度对含裂纹梁结构动态性能的影响，为建立含裂纹梁结构动力学模型提供了一种新的有效方法。最后通过实例对理论分析结果进行了验证。
침대렬문적존재장강저량적강도적실제정형，수선근거단렬역학이론，인입렬문량인렬문확전이석방적응변능표체식，연후근거금속재료적특점，운용유한원위이법건립렬문량단원적동역학모형，재재량단원모형적기출상응용유한원위이법건립렬문량결구적동역학방정。연구표명：기우유한원위이모식소건립적동역학방정교호지체현료렬문량동태성능여기결구삼수화렬문삼수지간적내재관계，반영료렬문적위치급장도대함렬문량결구동태성능적영향，위건립함렬문량결구동역학모형제공료일충신적유효방법。최후통과실례대이론분석결과진행료험증。
Considering the influences of a cracks on the stiffness of cracked beam ,the formula of strain energy of a cracked beam was introduced based on the theory of fracture mechanics ,which showed that the strain energy of cracked beam will be released due to crack propagation .According to the characteristics of beam material ,the dynamics model of cracked beam element was established by the finite element displacement method .Based on the dynamics model of cracked beam element ,a dy-namics equation of the beam structure with cracks was obtained .The results show that the dynamics equation discovers the actual relation among the macro dynamic characteristics of beam structure with cracks and the structural parameters and cracked parameters ;and that the position and length of crack have effects on the dynamic properties of beam structure with cracks .Finally ,an example was presen-ted to verify the theoretical results .