东南大学学报（自然科学版）
東南大學學報（自然科學版）
동남대학학보（자연과학판）
JOURNAL OF SOUTHEAST UNIVERSITY
2014年
6期
1254-1259
,共6页
箱梁%合龙段%底板%崩裂%成因
箱樑%閤龍段%底闆%崩裂%成因
상량%합룡단%저판%붕렬%성인
box girder%closure segment%bottom slab%split%cause
基于非线性有限元数值模拟方法，考虑混凝土非线性力学特性，建立了包含竖向双层波纹管孔道的精细化数值有限元模型，分析了箱梁合龙段底板从开始加载至最终破坏的损伤发展过程。基于精细化数值模型分析结果，讨论了崩裂成因。研究表明，箱梁合龙段底板崩裂成因共有5种：孔肋间混凝土竖向受拉、波纹孔道下方混凝土冲切、孔肋顶部和底部混凝土横向开裂、波纹管与混凝土的剥离以及底板弯曲开裂和梗腋位置剪切开裂。根据5种崩裂成因出现的先后顺序，认为控制底板崩裂破坏形式为波纹管下方混凝土冲切破坏及孔肋间竖向受拉破坏。最后，提出了孔肋间受拉破坏承载能力设计公式和底板抗冲切承载能力设计公式。
基于非線性有限元數值模擬方法，攷慮混凝土非線性力學特性，建立瞭包含豎嚮雙層波紋管孔道的精細化數值有限元模型，分析瞭箱樑閤龍段底闆從開始加載至最終破壞的損傷髮展過程。基于精細化數值模型分析結果，討論瞭崩裂成因。研究錶明，箱樑閤龍段底闆崩裂成因共有5種：孔肋間混凝土豎嚮受拉、波紋孔道下方混凝土遲切、孔肋頂部和底部混凝土橫嚮開裂、波紋管與混凝土的剝離以及底闆彎麯開裂和梗腋位置剪切開裂。根據5種崩裂成因齣現的先後順序，認為控製底闆崩裂破壞形式為波紋管下方混凝土遲切破壞及孔肋間豎嚮受拉破壞。最後，提齣瞭孔肋間受拉破壞承載能力設計公式和底闆抗遲切承載能力設計公式。
기우비선성유한원수치모의방법，고필혼응토비선성역학특성，건립료포함수향쌍층파문관공도적정세화수치유한원모형，분석료상량합룡단저판종개시가재지최종파배적손상발전과정。기우정세화수치모형분석결과，토론료붕렬성인。연구표명，상량합룡단저판붕렬성인공유5충：공륵간혼응토수향수랍、파문공도하방혼응토충절、공륵정부화저부혼응토횡향개렬、파문관여혼응토적박리이급저판만곡개렬화경액위치전절개렬。근거5충붕렬성인출현적선후순서，인위공제저판붕렬파배형식위파문관하방혼응토충절파배급공륵간수향수랍파배。최후，제출료공륵간수랍파배승재능력설계공식화저판항충절승재능력설계공식。
Based on the nonlinear finite element numerical simulation method,a refinement numeri-cal finite element model including vertical double layer bellows is set up considering the nonlinear mechanic characteristic of concrete.The damage evolution at the bottom slab in the closure segment of a box girder is analyzed from the beginning of loading till final destruction.According to the anal-ysis results of the refinement numerical model,the causes of split are summarized.The results show that there are five causes of split at the bottom slab in the closure segment of the box girder,inclu-ding vertical tensile between bellows,punch-shear of concrete below bellows,transverse cracking at the top and bottom of the rib,debonding between concrete and bellows,bending cracking at the bot-tom of the slab and shear cracking at haunch of the bottom of the slab.The punch-shear damage of concrete below bellows and the vertical tensile damage between bellows are considered as the control cause of split of the bottom slab according to the order of five kinds of split.Finally,the bearing ca-pacity formulas of vertical tensile damage between bellows and punch-shear damage below bellows of the bottom slab are presented,respectively.
