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瀝青砼路面常見(jiàn)的病害及防護(hù)畢業(yè)論文-文庫(kù)吧在線文庫(kù)

  

【正文】 青用量偏高或細(xì)料偏多,熱穩(wěn)定性不好,在夏季氣溫較高時(shí),不足以抵抗行車(chē)引起的水平力。 ( 2)鋪設(shè)瀝青面層前,未將下層表面清掃干凈或未噴灑粘層瀝青,致使上層與下層粘 結(jié)不良,產(chǎn)生滑移。 (3)粘層油用量不當(dāng) : 噴灑過(guò)多或?yàn)⒉疾痪鶆蛞矔?huì)局部出現(xiàn)泛油。 表現(xiàn)形式 松散是直接影響行車(chē)安全的路面病害,松散可能出現(xiàn)在整個(gè)路面表面。對(duì)于剝落而言,關(guān)鍵是集料對(duì)水的吸附能力的大小,親水性材料對(duì)水的吸附能力比瀝青大,而憎水性材料恰好相反。松散的集料表面光溜溜的,瀝青膜已剝落殆盡 ,這是典型水損害現(xiàn)象 ??偨Y(jié)為以下幾個(gè)方面: (1)瀝青混合料油石比過(guò)大; (2)表面磨損過(guò)度; (3)雨水侵入瀝青混凝土內(nèi)部; (4)瀝青混凝土配比設(shè)計(jì)不準(zhǔn)確 ; (5) 環(huán)境溫度過(guò)高 ; (6) 行車(chē)渠化交通 ; (7) 超載行車(chē)荷載的作用 ; 河北 聯(lián)合大學(xué)輕工學(xué)院本科畢業(yè)論文 6 (8) 環(huán)境溫度過(guò)高 ; (9) 施工時(shí)瀝青混凝土的壓實(shí)度不足,通車(chē)后在行車(chē)荷載的下進(jìn)一步密實(shí) ; (10)瀝青質(zhì)量不合格,瀝青的黏度低。與荷載有關(guān),通常發(fā)生在輪跡帶處??梢允菃螚l裂縫,或者是一系列平行的裂縫,有可能有支縫。荷載型裂縫首先在路面的底面發(fā)生,逐漸向上擴(kuò)展至表面。由于平行交叉作業(yè),加上工期較緊,對(duì)路面質(zhì)量產(chǎn)生影響,如在土基碾壓成型以后,管線單位又挖溝下管,管線單位對(duì)回填土的壓實(shí)質(zhì)量普遍不重視,因此造成局部不均勻沉降;又如瀝青混凝土攤鋪底面層、中面層時(shí) ,道路照明施工單位要進(jìn)行燈桿和電纜的鋪設(shè),而且不能封閉交通,導(dǎo)致路面污染嚴(yán)重,從而使路面層與層之間的粘結(jié)受到影響,特別是當(dāng)瀝青面層較薄時(shí),在車(chē)輛高速行駛載荷作用下,瀝青路面產(chǎn)生脫落、擁包、扭曲裂縫等現(xiàn)象。降溫幅度由表及 里逐漸減少,最嚴(yán)重的降溫區(qū)發(fā)生在堆料表面和馬槽的接觸面。在施工時(shí),有的單位壓縮兩至三個(gè)階段,有的干脆憑經(jīng)驗(yàn)進(jìn)行施工。由于瀝青面層在路面中是受到約束的,面層中產(chǎn)生的收縮拉應(yīng)力或拉應(yīng)變一旦超過(guò)瀝青混合料的抗拉強(qiáng)度,瀝青面層就會(huì)開(kāi)裂,產(chǎn)生裂縫。在冬季低溫下,瀝青材料會(huì)由于收縮作用而產(chǎn)生脆裂破壞。對(duì)此,本文就以上幾種常見(jiàn)病害的成因進(jìn)行分析并結(jié)合實(shí)際提出相應(yīng)的預(yù)防措施。 prevention of roadperformance of asphalt pavement 目錄 II 目錄 摘要 ............................................................................................................................... Ⅰ Abstract......................................................................................................................... Ⅱ .............................................................................................................................. 3 ................................................................................................. 2 ............................................................................... 4 ..................................................................................................... 4 碎石質(zhì)量問(wèn)題 ...................................................................................................... 1 ......................................................................................................... 1 ...................................................................... 2 瀝青混凝土拌合溫度的控制 ................................................................................ 2 、粘層油對(duì)路面的影 響 ............................................................................. 2 ....................................................................................... 3 ......................................................................... 3 ........................................................................ 3 ................................................................................................................... 3 .................................................................................................. 4 .................................................................................................. 4 .................................................................................................. 4 ................................................................................................................... 5 .............................................................................................. 6 .............................................................................................. 6 .............................................................................................. 6 ................................................................................................................ 6 .................................................................................................. 7 .................................................................................................. 7 ............................................................................................................ 7 .................................................................................................. 8 .................................................................................................. 8 ................................................................................................................... 8 .................................................................................................. 8 .................................................................................................. 9 ................................................................................................................... 9 .................................................................................................. 9 目錄 III .................................................................................................. 9 ................................................................................................................. 10 ....................................................................................................... 10 ................................................................................................ 10 ................................................................................................................. 10 ....................................................................................................... 10 .................................................................................................11 ...........................................................................................................11 .................................................................................................................11 .................................................................................................................11 ..................................................................................11 ......................................................................................11 ......................
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