中国机械工程
中國機械工程
중국궤계공정
CHINA MECHANICAl ENGINEERING
2015年
17期
2308-2313,2314
,共7页
风振%疲劳寿命%高耸塔器%风载荷
風振%疲勞壽命%高聳塔器%風載荷
풍진%피로수명%고용탑기%풍재하
wind-induced vibration%fatigue life%high-rising column%wind load
针对沿海多风地区高耸塔器可能因长期风致振动导致的疲劳问题,以随机风致应力响应的时程模拟、风速风向联合分布模型、雨流法以及 Miner 疲劳累积损伤理论为基础,提出了基于时域法的高耸塔器风致疲劳寿命数值计算方法,并针对某一典型高耸塔器进行了相关分析。结果表明:长时间的空塔工况可能导致该塔器严重的疲劳损伤甚至失效,而操作工况下的风致疲劳寿命一般可以满足设计年限要求;横风向共振是引起该塔器空塔工况风致疲劳的决定性因素,而强风造成的顺风向振动是导致其操作工况下疲劳损伤的主要原因;该塔器空塔和操作工况下的疲劳分布曲线分别呈多峰型和单峰型,可见顺风向的疲劳损伤比横风向更为集中。
針對沿海多風地區高聳塔器可能因長期風緻振動導緻的疲勞問題,以隨機風緻應力響應的時程模擬、風速風嚮聯閤分佈模型、雨流法以及 Miner 疲勞纍積損傷理論為基礎,提齣瞭基于時域法的高聳塔器風緻疲勞壽命數值計算方法,併針對某一典型高聳塔器進行瞭相關分析。結果錶明:長時間的空塔工況可能導緻該塔器嚴重的疲勞損傷甚至失效,而操作工況下的風緻疲勞壽命一般可以滿足設計年限要求;橫風嚮共振是引起該塔器空塔工況風緻疲勞的決定性因素,而彊風造成的順風嚮振動是導緻其操作工況下疲勞損傷的主要原因;該塔器空塔和操作工況下的疲勞分佈麯線分彆呈多峰型和單峰型,可見順風嚮的疲勞損傷比橫風嚮更為集中。
침대연해다풍지구고용탑기가능인장기풍치진동도치적피로문제,이수궤풍치응력향응적시정모의、풍속풍향연합분포모형、우류법이급 Miner 피로루적손상이론위기출,제출료기우시역법적고용탑기풍치피로수명수치계산방법,병침대모일전형고용탑기진행료상관분석。결과표명:장시간적공탑공황가능도치해탑기엄중적피로손상심지실효,이조작공황하적풍치피로수명일반가이만족설계년한요구;횡풍향공진시인기해탑기공탑공황풍치피로적결정성인소,이강풍조성적순풍향진동시도치기조작공황하피로손상적주요원인;해탑기공탑화조작공황하적피로분포곡선분별정다봉형화단봉형,가견순풍향적피로손상비횡풍향경위집중。
The long-term wind-induced vibration would cause fatigue failure of high-rising col-umns in windy coastal areas.Therefore,a numerical method of wind-induced fatigue life calculation for high-rising columns was proposed,based on time-history simulation of random wind-induced stress responses,joint distribution model of wind speed and wind direction,rain-flow method and Miner fatigue cumulative damage rule.Then a typical example illustrated the method and indicates that serious fatigue damage or failure might will be induced by the long time empty conditions for this column,while the wind-induced fatigue life in the operating conditions can meet the design demand;cross-wind resonance is the decisive factor of wind-induced fatigue for this empty column,compared with the along-wind vibration producing the mainly fatigue damage in operating conditions caused by the strong wind.The difference of fatigue distribution curves that one with single peak and the other several peaks in the empty and operating conditions shows the along-wind fatigue damage is more con-centrated than that of the cross-wind.