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
1240-1245
,共6页
再生混凝土%再生粗骨料%随机分布%氯离子扩散%细观数值模拟
再生混凝土%再生粗骨料%隨機分佈%氯離子擴散%細觀數值模擬
재생혼응토%재생조골료%수궤분포%록리자확산%세관수치모의
recycled aggregate concrete (RAC)%recycled coarse aggregate (RCA)%random distri-bution%chloride diffusion%mesoscopic numerical simulation
考虑粗骨料分布的随机性及氯离子结合的非线性对氯离子扩散性的影响,对再生混凝土中氯离子扩散进行数值建模与细观仿真分析,并将数值模拟结果与已有试验数据进行对比;通过改变老硬化砂浆扩散系数、新硬化砂浆扩散系数、老界面过渡区扩散系数及浸泡时间,对比研究了不同情况下再生混凝土中氯离子的扩散特性。结果表明:数值模拟结果与试验结果接近;再生混凝土中氯离子沿扩散深度方向呈波浪式下降;随着扩散系数的增大及浸泡时间的增长,氯离子扩散速度加快;随着再生粗骨料取代率的增加,氯离子扩散速度也增加;相同扩散深度处,不同随机骨料模型中氯离子含量最大值接近,说明所采用的随机骨料模型模拟结果具有较好的稳定性。
攷慮粗骨料分佈的隨機性及氯離子結閤的非線性對氯離子擴散性的影響,對再生混凝土中氯離子擴散進行數值建模與細觀倣真分析,併將數值模擬結果與已有試驗數據進行對比;通過改變老硬化砂漿擴散繫數、新硬化砂漿擴散繫數、老界麵過渡區擴散繫數及浸泡時間,對比研究瞭不同情況下再生混凝土中氯離子的擴散特性。結果錶明:數值模擬結果與試驗結果接近;再生混凝土中氯離子沿擴散深度方嚮呈波浪式下降;隨著擴散繫數的增大及浸泡時間的增長,氯離子擴散速度加快;隨著再生粗骨料取代率的增加,氯離子擴散速度也增加;相同擴散深度處,不同隨機骨料模型中氯離子含量最大值接近,說明所採用的隨機骨料模型模擬結果具有較好的穩定性。
고필조골료분포적수궤성급록리자결합적비선성대록리자확산성적영향,대재생혼응토중록리자확산진행수치건모여세관방진분석,병장수치모의결과여이유시험수거진행대비;통과개변로경화사장확산계수、신경화사장확산계수、로계면과도구확산계수급침포시간,대비연구료불동정황하재생혼응토중록리자적확산특성。결과표명:수치모의결과여시험결과접근;재생혼응토중록리자연확산심도방향정파랑식하강;수착확산계수적증대급침포시간적증장,록리자확산속도가쾌;수착재생조골료취대솔적증가,록리자확산속도야증가;상동확산심도처,불동수궤골료모형중록리자함량최대치접근,설명소채용적수궤골료모형모의결과구유교호적은정성。
Concerning the effects of the random distribution of coarse aggregate and the non-linear characteristic of chloride binding on chloride diffusion,the modeling and microscopic simulation analysis for the chloride diffusion characteristics of recycled aggregate concrete (RAC )are carried out.The simulation results are compared with the test results.Then,the chloride diffusion character-istics with different diffusion coefficients of old mortar,new mortar and old interfacial transition zone (ITZ)and different immersion times are studied.The results indicate that the simulation results and the test results are similar.The distribution of chloride diffusion in RAC declines wavily along the diffusion depth.The chloride diffusion speed accelerates with the increase of the diffusion coeffi-cients and the immersion time.Besides,with the increase of the replacement percentage of recycled coarse aggregate (RCA ),the chloride diffusion speed of RAC increases.At the same diffusion depth,the maximum chloride concentrations in different random RAC models are similar,indicating that the simulation results of the proposed random RAC model has a good stability.