發(fā)布時間：2018-11-25 07:19

【摘要】：隨著我國交通事業(yè)的發(fā)展,對路面材料研究的逐步深入,重視瀝青與瀝青混合料的粘彈性行為及路用性能已經(jīng)成為了研究瀝青路面的一個趨勢。本文采用大連理工大學(xué)道路教研室自主開發(fā)的瀝青旋轉(zhuǎn)剪切蠕變試驗儀,對不同種類瀝青的蠕變性能進行了分析與評價,旨在為瀝青粘彈性力學(xué)行為的研究與應(yīng)用提供一種新的方法與手段,促進粘彈性理論及其試驗設(shè)備與方法在瀝青路面試驗測試中的應(yīng)用。 本文首先介紹了瀝青旋轉(zhuǎn)剪切蠕變試驗儀的工作原理與試驗方法,選取了6種具有代表性的瀝青并對其進行了基礎(chǔ)試驗。 第二,采用蠕變試驗儀研究了不同種類瀝青、溫度及應(yīng)力水平對瀝青單次蠕變的蠕變應(yīng)變、蠕變回復(fù)率、蠕變勁度等蠕變指標(biāo)的影響規(guī)律。研究結(jié)果表明,同一應(yīng)力水平下瀝青的蠕變應(yīng)變隨溫度上升而增大,且增大的幅度越來越大,蠕變回復(fù)率和蠕變勁度隨著溫度升高不斷減��；20℃較低應(yīng)力水平下,應(yīng)力水平對蠕變勁度的影響很小,多數(shù)瀝青的蠕變回復(fù)率隨著應(yīng)力水平的增加逐漸減��；冪函數(shù)S(t)=Bt(-m)能夠很好的表征瀝青蠕變勁度與時間的關(guān)系；標(biāo)號不同的基質(zhì)瀝青之間蠕變性能差別很大,改性劑的添加可以有效減小瀝青的總變形,并且提高變形中的彈性變形的比例,老化過程可以很大程度的改變?yōu)r青的蠕變性能,再生劑的添加可以增加老化瀝青中的粘性成分,恢復(fù)瀝青的粘彈性性質(zhì)。 第三,采用蠕變試驗儀研究了瀝青種類、應(yīng)力水平和蠕變次數(shù)對瀝青重復(fù)蠕變回復(fù)性能的影響。研究結(jié)果表明,20℃時,不同種類瀝青的蠕變回復(fù)率相差很大,基質(zhì)瀝青和再生瀝青的蠕變回復(fù)率都比較小,改性瀝青和老化瀝青的蠕變回復(fù)率比較大；重復(fù)蠕變回復(fù)試驗更能區(qū)分改性瀝青的粘彈性性質(zhì)；20℃較低應(yīng)力水平下,蠕變回復(fù)率會隨著荷載作用次數(shù)的增加逐漸增加,并趨向穩(wěn)定,單次最大剪應(yīng)變隨著荷載作用次數(shù)的增加不斷減小,并逐漸趨向穩(wěn)定。 最后,采用低溫彎曲梁流變儀(BBR)試驗對不同種類瀝青的低溫蠕變性能進行了研究,結(jié)果表明：老化過程增加了瀝青的低溫蠕變勁度,并且減小了瀝青的勁度變化率,從而降低了瀝青的低溫性能；而再生過程能夠有效地降低瀝青的低溫勁度,增加瀝青的勁度變化率；改性瀝青能夠有效降低瀝青的低溫蠕變勁度,但是同時也減小了瀝青的勁度變化率,對于改性瀝青應(yīng)該結(jié)合其他試驗來評價其低溫性能；Burgers模型可以有效地描述基質(zhì)瀝青、改性瀝青、老化瀝青和再生瀝青的粘彈性,進一步證明了采用Burgers模型擬合瀝青材料的合理性。
[Abstract]:With the development of transportation industry in China, the research on pavement materials has been deepened step by step. It has become a trend to pay attention to the viscoelastic behavior and road performance of asphalt and asphalt mixture. In this paper, the creep properties of different kinds of asphalt are analyzed and evaluated by using the rotary shear creep tester developed by the road teaching and research department of Dalian University of Technology. The purpose of this paper is to provide a new method and means for the study and application of viscoelastic behavior of asphalt, and to promote the application of viscoelastic theory and its testing equipment and method in asphalt pavement test. In this paper, the working principle and test method of asphalt rotary shear creep tester are introduced. Six kinds of representative asphalt are selected and the basic tests are carried out. Secondly, the effects of different asphalt, temperature and stress levels on creep strain, creep recovery rate and creep stiffness of asphalt were studied by using creep tester. The results show that the creep strain of asphalt increases with the increase of temperature, and the creep recovery rate and creep stiffness decrease with the increase of temperature. At the low stress level of 20 鈩，

本文編號：2355271