- 摘 要
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王磊1，2，李泉龍2，陳杏2
（1 廣西建筑新能源與節(jié)能重點實驗室, 桂林 541004；
2 桂林理工大學(xué)土木與建筑工程學(xué)院， 桂林 541004）
［摘要］完成了0%,30%,50%,70%,100%再生粗骨料取代率下混凝土的彈性模量、濕熱變形性能以及不同齡期的收縮率測試，分析了影響再生混凝土干縮性能的因素。研究結(jié)果表明，不同取代率的再生混凝土早期收縮率差值并不明顯，收縮量與再生粗骨料取代率也無明顯相關(guān)性，40～50d后，隨著再生粗骨料取代率的提高，再生混凝土的干縮率顯著增加，與天然混凝土收縮率之間的差值開始擴大，50～220d是再生混凝土與天然混凝土收縮率差距擴大的主要階段，100%取代率再生混凝土和天然混凝土收縮率的差距由50d的1.4倍增加到220d的2.4倍；再生粗骨料取代率越高的再生混凝土收縮趨于穩(wěn)定的齡期越長；再生混凝土的熱脹率、吸水膨脹率隨著再生粗骨料取代率的增加明顯增大。除了水灰比等常規(guī)因素外，再生粗骨料中舊砂漿含量對再生混凝土變形性能的實際影響最大，并通過顆粒級配、再生粗骨料取代率等反映出來，實際工程中應(yīng)合理控制再生粗骨料取代率以及小粒徑再生粗骨料的比重。
［關(guān)鍵詞］再生粗骨料； 再生混凝土； 取代率； 干縮性能； 砂漿含量
中圖分類號：X799.1， TU528.041文獻標識碼：A文章編號：1002-848X(2016)02-0030-05
Deformation property and influencing factor analyses of recycled coarse aggregate concrete
Wang Lei1，2， Li Quanlong2， Chen Xing2
（1 Guangxi Key Laboratory of New Energy and Building Energy Saving， Guilin 541004， China；
2 College of Civil Engineering and Architecture, Guilin University of Technology,
Guilin 541004, China）
Abstract:Tests were carried out on concrete elastic modulus, wet and thermal expansion properties, shrinkage ratios of different ages of recycled coarse aggregate concrete with recycled coarse aggregate (RCA) replacement percentages of 0%, 30%, 50%, 70% and 100%. The factors influencing shrinkage performance of the recycled concrete were analyzed. The research results show that the gap of early age shrinkage of recycled concrete with different replacement ratios is not obvious. The relationship between shrinkage percentage and the RCA replacement ratio is not significant in early age. With the increase of the RCA replacement ratio after 40~50d age, the shrinkage ratio of recycled concrete increases significantly and the gap of shrinkage ratio between recycled concrete and natural aggregate concrete begins to expand. The stage from 50d to 220d age is the main period when gap of shrinkage ratio between recycled concrete and natural aggregate concrete expands and the shrinkage ratio gap between RCA with 100% replacement ratio and natural concrete increases from 1.4 times at 50d to 2.4 times at 220d. The recycled concrete with higher RCA replacement ratio has a longer shrinkage age. The wet and thermal expansion ratio and swelling ratio of recycled concrete increase significantly with the increase of the RCA replacement ratio. In addition to the conventional factors as water-cement ratio, the old mortar content of RCA has the significant impact on the deformation performance of recycled concrete, which is reflected in particle size distribution and RCA replacement ratio. In practical engineering, RCA replacement ratio should be reasonably controlled as well as percentage of RCA with small particle size.
Keywords:recycled coarse aggregate(RCA); recycled concrete； replacement ratio; shrinkage performance；mortar content
*國家自然科學(xué)基金（51268009），廣西自然基金（2012GXNSFBA053151）,廣西高校中青年骨干教師資助計劃。
作者簡介：王磊，博士，教授，Email：tianmu77@163.com。
