瀝青路面病害類型及產(chǎn)生原因預(yù)防治理措施

1、<p><b>　　目 錄</b></p><p>　　第一章 緒 論...........................................1</p><p>　　第二章 常見瀝青路面病害類型及產(chǎn)生原因..................2</p><p>　　2.1 裂縫.......................

2、........................2</p><p>　　2.2 路面推移...........................................3</p><p>　　2.3 泛油和油斑.........................................4</p><p>　　2.4 車轍.................

3、..............................4</p><p>　　第三章 病害防治技術(shù)和處理方法..........................6</p><p>　　3.1 裂縫的預(yù)防措施和治理措施...........................6</p><p>　　3.2 路面推移以及泛油和油斑的預(yù)防措施和治理措施.........

4、9</p><p>　　3.3 車轍預(yù)防措施和治理.................................9</p><p>　　第四章 結(jié)束語.........................................11</p><p>　　參考文獻(xiàn)..............................................12&

5、lt;/p><p>　　致謝..................................................13</p><p>　　外語翻譯..............................................14</p><p><b>　　摘 要</b></p><p>　　

6、本文分析了常見瀝青路面病害類型及產(chǎn)生原因，闡明了瀝青路面早期裂縫造成原因和后果, 影響車輛的行駛舒適性，造成道路行車安全隱患。對瀝青混凝土路面產(chǎn)生裂縫的預(yù)防與處理，是保證行車質(zhì)量，延長道路使用周期的關(guān)鍵。針對當(dāng)前瀝青路面普遍存在的病害問題,提出了簡便有效防治措施,以提高瀝青路面的使用壽命, 針對病害提出了病害防治技術(shù)和處理方法。</p><p>　　隨著高速公路的的飛速發(fā)展,瀝青混凝土路面得到了廣泛的應(yīng)用,但道路

7、裂縫成為普遍存在且對道路危害較為嚴(yán)重的病害之一,因此探索高速公路瀝青混凝土路面裂縫成因及防治措施,提高其使用壽命就顯得優(yōu)為重要。　　</p><p>　　關(guān)鍵詞：瀝青路面　病害　處理方法 　　 　　</p><p><b>　　Abstract</b></p><p>　　In this paper the common asphalt

8、pavement disease types and causes of asphalt pavement, expounds the causes and consequences caused by early cracks, the influence of vehicle driving comfort, road traffic safety hazard. The asphalt concrete pavement for

9、prevention and treatment of cracks is to guarantee the quality and prolong driving cycle of road use. In view of the current asphalt pavement widespread disease problems, and put forward effective prevention measures in

10、order to improve the servic</p><p>　　Along with the rapid development of expressway asphalt concrete pavement, and has been widely used, but the road to crack exists and become more serious diseases road har

11、m one, so to explore expressway asphalt concrete pavement of crack causes and prevention measures to improve its service life is optimal for important.</p><p>　　Keywords: asphalt pavement processing methods&

12、lt;/p><p>　　第一章 緒 論　　 　　近幾年，隨著我國公路建設(shè)的發(fā)展，使我公司負(fù)責(zé)管理養(yǎng)護(hù)的高速公路里程已達(dá)到了1092公里，瀝青混凝土路面以其比單純的混凝土路面具有諸多優(yōu)勢特點(diǎn)，而越來越多地被應(yīng)用到高等級公路建設(shè)中，但是瀝青混凝土路面的一些問題卻不容忽視。在各種因素的影響下，不可避免的會(huì)出現(xiàn)很多病害，瀝青混凝土大部分設(shè)計(jì)年限為15年。然而部分地區(qū)局部路段路面使用年限2年都不足，既影響使用功效又浪費(fèi)資源

13、?，F(xiàn)就我區(qū)最早建成通車呼包高速公路（1997年7月建成通車）及其輔道（二級公路）發(fā)生的一些裂縫病害的危害、類型分類、成因及防治措施進(jìn)行簡要的研究探討。</p><p>　　第二章 常見瀝青路面病害類型及產(chǎn)生原因 　　 　　瀝青路面的病害產(chǎn)生是多種因素綜合作用的結(jié)果，其種類繁多，但主要表現(xiàn)為裂縫、車轍、沉陷、坑槽、唧泥、泛油、波浪、擁包、表面磨光、松散剝落等?，F(xiàn)就瀝青混凝土路面最常見的裂縫、路面推移、泛油和油斑

14、、車轍產(chǎn)生的原因進(jìn)行分析。 2.1裂縫 2.1.1橫向裂縫：</p><p>　　裂縫與路中心線基本垂直，縫寬不一，縫長貫穿部分路幅或整個(gè)路幅。裂縫一般比較規(guī)則，每隔一定的距離產(chǎn)生一道裂縫，裂縫間距的大小取決于當(dāng)?shù)氐臍鉁睾蜑r青面層與半剛性基層材料的抗裂性能。 2.1.2縱向裂縫：</p><p>　　裂縫走向基本與行車方向平行，裂縫長度和寬度不一。主要集中在行車道輪跡分布密集處，因?yàn)?/p>

15、高速公路交通渠化分明，輪跡位置及輪跡分布范圍較小。大車、慢車、重型車輛全部集中在行車道上，快車、小型車，輕型車行駛于超車道機(jī)會(huì)明顯增多，超車道上荷載較小，交通量相對較小，縱向裂縫也較小，縱縫縫寬一般在5～10mm，靠近標(biāo)線或位于車道中央，且綿延幾十米，甚至數(shù)百米。常以單條裂縫形式出現(xiàn)。產(chǎn)生的原因有兩種可能性，一種情況是瀝青面層分路幅攤鋪時(shí)，兩幅接茬處未處理好，在車輛荷載及大氣因素作用下逐漸開裂；另一種情況是由于路基壓實(shí)度不均勻或由于路基

16、邊緣受水侵蝕產(chǎn)生不均勻沉陷而引起。 2.1.3網(wǎng)狀裂縫：</p><p>　　裂縫縱橫交錯(cuò)?？p寬1mm以上，縫距40cm以下，1m2以上。 2.1.4反射裂縫：</p><p>　　基層產(chǎn)生裂縫后，在溫度和行車荷載作用下，裂縫將逐漸反射到瀝青表面，路表面裂縫的位置形狀與基層裂縫基本相似。半剛性基層的開裂通常由溫縮或干縮引起，多數(shù)情況是在基層鋪筑后，由于未按規(guī)定及時(shí)養(yǎng)生或未及時(shí)鋪筑瀝青面

17、層，使基層長期暴露在大氣中，在降溫和水分聯(lián)合作用下而開裂。 　　筆者在郊環(huán)線病害發(fā)生地點(diǎn)實(shí)際觀察過發(fā)現(xiàn)，在“白改黑”路段和橋頭回填路段反射裂縫病害比較普遍。究其原因，“白改黑”路段原設(shè)計(jì)“白色”路面設(shè)計(jì)年限和標(biāo)準(zhǔn)相對現(xiàn)在而言低，且路基設(shè)計(jì)標(biāo)準(zhǔn)也是參照以往的交通情況和要求，在瀝青路面施工后，重交通荷載下，“白色”路面產(chǎn)生裂縫，反射到瀝青路面；橋頭回填路段主要是因?yàn)檐浕范尾痪鶆虺两狄鸬牧芽p直接反射到瀝青路面。 　　另外，行車荷載的作

18、用加速裂縫的發(fā)展，二灰碎石在施工及運(yùn)營中由于種種原因會(huì)產(chǎn)生細(xì)微裂紋。根據(jù)斷裂力學(xué)理論，半剛性基層內(nèi)存儲的能量由行車荷載提供，并通過裂紋失穩(wěn)擴(kuò)展消耗能量，這個(gè)過程不斷反復(fù)進(jìn)行，使獨(dú)立的裂紋擴(kuò)展為數(shù)條貫通宏觀裂紋，直到形成小裂縫，最后成為貫穿裂縫。這是行車道裂縫多于超車道，變通量軸載次數(shù)大裂縫多于交通量小原因所在。 2.2路面推移 　　瀝青混凝土面層推移</p><p>　　第三章 病害防治技術(shù)和處理方法 　　

19、</p><p>　　3.1裂縫的預(yù)防措施和治理措施</p><p>　　產(chǎn)品生產(chǎn)前對原材料特別是瀝青做試驗(yàn)，根據(jù)《瀝青路面施工及驗(yàn)收規(guī)范》(gb50092)要求，按本地區(qū)氣候條件和道路等級選取適用的瀝青類型。以減少或消除瀝青面層溫度收縮裂縫。采用優(yōu)質(zhì)瀝青更有效。瀝青路面裂縫產(chǎn)生后，應(yīng)及時(shí)予以處理，防止水等有害物質(zhì)侵入，影響道路使用壽命。目前我公司采用的裂縫維修方法主要有以下幾個(gè)類型：&

20、lt;/p><p>　　3.1.1普通瀝青或改性瀝青灌縫處理</p><p>　　呼包高速公路輔道（舊G110國道）二級公路上對于細(xì)裂縫(2～5mm)可用乳化瀝青進(jìn)行灌縫處理；對于大于5mm的粗裂縫，可用改性瀝青(如SBS改性瀝青)進(jìn)行灌縫處理；在灌縫前，必須清除縫內(nèi)、縫邊碎料、垃圾等，并保證縫內(nèi)干燥；在灌縫后，表面應(yīng)灑布粗砂或3～ 5mm的石屑。優(yōu)點(diǎn)：施工要求技術(shù)難度低，施工簡便，投資少，見

21、效快。缺點(diǎn)：行車感不好，治標(biāo)不治本，短期行為，過不了不久又會(huì)出現(xiàn)。</p><p>　　3.1.2路面裂縫修補(bǔ)專業(yè)密封膠灌縫處理</p><p>　　呼包高速公路大部分路段，裂縫寬度在1cm以下的可采用密封膠進(jìn)行灌縫處理?，F(xiàn)在國內(nèi)市場上密封膠種類很多，多為代理國外廠家產(chǎn)品，國產(chǎn)的密封膠也在近幾年出現(xiàn)，但質(zhì)量不是很穩(wěn)定。在內(nèi)蒙古地區(qū)選用的密封膠，應(yīng)采用適合在寒帶（或寒溫帶）使用的標(biāo)準(zhǔn)型號，適

22、用溫度為-30℃--38℃之間。密封膠灌縫必須采用專業(yè)路面灌縫機(jī)，施工季節(jié)應(yīng)選在春秋兩季，路面地表溫度應(yīng)達(dá)到4℃以上為宜（如達(dá)不到必須使用熱吹槍對路面加溫）且在陰雨天氣不允許施工。灌注前應(yīng)對路面裂縫進(jìn)行開槽，開出的槽寬度為12.7mm，深度為12.7mm（寬：深為1：1最佳）開槽后用空壓機(jī)將槽內(nèi)的水分、灰塵、雜物及裂縫周邊松動(dòng)的物體清除干凈，保持裂縫的清潔和干燥。灌注時(shí)密封膠必須在具有雙層保溫層、間接導(dǎo)熱油加熱的攪拌式鍋爐內(nèi)熔化，加熱溫

23、度不得超過199℃，出料時(shí)溫度不低于188℃，將密封膠均勻灌入槽內(nèi)。如裂縫較深可采用膨脹條或墊襯物填充后再進(jìn)行密封膠灌注，以控制密封膠用量。理想的密封層表面應(yīng)比裂縫（接縫）略寬一點(diǎn)，以確保密封膠與裂縫兩壁的緊密粘結(jié)，并且在裂縫表面形成T字型密封膠層，以提高防水性能。優(yōu)點(diǎn)：裂縫防水性提高，行車平順感較好，裂縫不至于短期</p><p>　　3.1.3對路面裂縫段落采用加鋪抗裂帖維修處理</p><

24、;p>　　呼包高速公路少部分路段裂縫發(fā)展，寬度超過1cm，并且出現(xiàn)輕度網(wǎng)裂現(xiàn)象。類似病害雖然不多但由于此類病害危害極大，可能致使大面積病害發(fā)生，且采用一般灌縫的處理手段很難達(dá)到治理效果。為了達(dá)到最大限度減少道路裂縫的目的，我公司嘗試采用了高分子聚合物抗裂貼對存在嚴(yán)重裂縫病害的近1公里的試驗(yàn)路段進(jìn)行了處理?？沽奄N是一種優(yōu)質(zhì)的道路高分子聚合物改性材料，并復(fù)合了高強(qiáng)胎基和耐高溫織物，對道路的反射裂縫具有良好的防治作用，并具有良好的防水效

25、能。采用抗裂貼寬度為48cm，首先將存在病害的路段路面進(jìn)行銑刨，露出基層。將基層表面清理干凈在存在裂縫的部位將粘附表面灰塵和水清除干凈，保持路面干燥清潔，對于裂縫較寬的先用密封膠將縫填充，并保證基層表面的平整。鋪設(shè)時(shí)將隔離膜（紙）揭掉，將抗裂貼貼在裂縫部位，在鋪設(shè)時(shí)應(yīng)將成卷的材料拉緊，鋪設(shè)應(yīng)平整不得出現(xiàn)皺著或出現(xiàn)翹邊現(xiàn)象。鋪設(shè)過程如出現(xiàn)重疊應(yīng)保證重疊長度50—125mm。不能超過兩層以上的重疊。鋪設(shè)完畢后應(yīng)用膠輪滾筒進(jìn)行滾壓至少3遍。鋪

26、設(shè)完成后盡早在其上面進(jìn)行瀝青混凝土的攤鋪施工，鋪設(shè)與攤鋪的時(shí)間間隔一般不得少于24小時(shí)，且鋪設(shè)完后不得有施工車輛或人員在已鋪設(shè)好的抗裂貼</p><p>　　3.1.4合理組織施工，盡量避免冷接縫。</p><p>　　對于冷接縫的處理，應(yīng)先將接縫處沿邊緣切割整齊、清除碎料，然后預(yù)熱軟化接縫處，涂刷乳化瀝青，再鋪筑新混合料。碾壓時(shí)，壓路機(jī)在已壓實(shí)的橫幅上，鋼輪伸入新鋪層15cm左右，每壓一

27、遍向新鋪層移動(dòng)15～20cm，直到壓路機(jī)全部在新鋪層為止。對于縱向裂縫，如分幅攤鋪時(shí)，前后幅應(yīng)緊跟，上、下層的施工縱縫應(yīng)錯(cuò)開15cm以上，攤鋪時(shí)控制好松鋪系數(shù)，使壓實(shí)后的接縫結(jié)合緊密、平整。1.3瀝青路面攤鋪前，對下臥層需認(rèn)真檢查，及時(shí)清除泥灰，處理好軟弱層，保證下臥層穩(wěn)定。在舊路面上加鋪瀝青路面結(jié)構(gòu)層前，須銑削原路面后再加鋪，以延緩反射裂縫的形成。 3.1.5在路面出現(xiàn)微小裂縫時(shí)就必須及時(shí)處理整治。</p><p

28、>　　對于細(xì)裂縫(2～5mm)可用改性乳化瀝青灌縫。對大干5mm的粗裂縫，可用改性瀝青(如橡膠類改性瀝青)灌縫。灌縫前，必須清除縫內(nèi)、縫邊碎粒、垃圾，并使縫內(nèi)干燥。灌縫后，表面撒上粗砂或3～5mm石屑。對裂縫很大的情況，必須將裂縫兩邊瀝青混凝土開挖，先處理基層再攤鋪新混合料，水穩(wěn)定性好、收縮性小的半剛性材料是首選基層。 3.2路面推移以及泛油和油斑的預(yù)防措施和治理措施： 　　提高混合料在壓實(shí)后的內(nèi)在穩(wěn)定性，適度降低瀝青和細(xì)集料

29、的含量，提高混合料中多角碎石顆粒的含量，施工攤鋪時(shí)盡量避免攪拌不勻的現(xiàn)象，如出現(xiàn)時(shí)可采用人工局部挑出。另外運(yùn)輸途中絕不能出現(xiàn)顛簸嚴(yán)重運(yùn)輸時(shí)間長情況。 　　出現(xiàn)路面推移情況時(shí)只能局部鏟除，采用符合要求的新混合料攤鋪，并與周邊的混合料結(jié)合緊密。 3.3車轍預(yù)防措施和治理措施： 　　主要是提高混合料的高溫穩(wěn)定性。近幾年來的改性瀝青混合料的生產(chǎn)施工實(shí)踐證明，采用改性瀝青混合料是防止或延緩路面產(chǎn)生車轍的有效方法。在瀝青中摻人不同的改性劑能改

30、善瀝青的很多性能，粘度提高，感溫性能穩(wěn)定，瀝青軟化點(diǎn)提高，針入度提高，耐老化性能提高，從而也相應(yīng)的提高了瀝青的高溫穩(wěn)定性和抗車轍能力</p><p><b>　　第四章 結(jié)束語</b></p><p>　　瀝青路面的病害必須從路基施工準(zhǔn)備階段就開始重視，所有公路建設(shè)工程的施工單位和養(yǎng)護(hù)單位都有義不容辭的責(zé)任、義務(wù)，都必須強(qiáng)化施工管理，完善施工工藝和施工方法，提高施工質(zhì)

31、量，才能從源頭上、根本上解決問題，社會(huì)效益和社會(huì)質(zhì)量得到保證。</p><p>　　主要病害裂縫的產(chǎn)生很大程度上是由于不規(guī)范施工造成的，只要積極采取有效措施，規(guī)范管理，合理組織施工工序，杜絕不利因素的發(fā)生，裂縫問題一定可以減少。對出現(xiàn)的裂縫因地制宜結(jié)合當(dāng)?shù)貙?shí)際情況選取合理的處理方法進(jìn)行處理，就可以最大限度避免裂縫病害的進(jìn)一步發(fā)展，確保道路使用壽命達(dá)到甚至超過設(shè)計(jì)使用壽命。</p><p>

32、<b>　　參考文獻(xiàn)</b></p><p>　　1、清華大學(xué)《混凝土結(jié)構(gòu)》中國建筑工業(yè)出版社 1994.6北京</p><p>　　2、交通部公路司.公路工程質(zhì)量通病指南.北京：人民交通出版社，2002。</p><p>　　3、中華人民共和國交通部發(fā)布.公路瀝青路面養(yǎng)護(hù)技術(shù)規(guī)范(JTJ073.2-----2001)北京：人民交通出版社，2

33、001</p><p><b>　　致 謝</b></p><p>　　感謝實(shí)習(xí)單位讓我學(xué)到了許多路基試驗(yàn)室的知識，讓我理論與實(shí)踐相結(jié)合能夠更好的完善所學(xué)到的知識。感謝學(xué)校，感謝我的所有任課老師讓我更多的了解道路橋梁。歷時(shí)半載，從論文選題到搜集資料，從開題報(bào)告、寫初稿到反復(fù)修改，期間經(jīng)歷了喜悅、聒噪、痛苦和彷徨，在寫作論文的過程中心情是如此復(fù)雜。如今，伴隨著這篇畢業(yè)

34、論文的最終成稿，復(fù)雜的心情煙消云散，自己甚至還有一點(diǎn)成就感。</p><p>　　And subgrade construction program</p><p>　　1.preparations</p><p>　　Construction lofting: sure road line and roadbed and covers an area of red

35、 edge</p><p>　　120, small structures built underground pipelines having set small structures and roadbed (earth), but the underground pipeline must follow the "first underground, after", "the

36、first deep shallow", after the guarantee the continuity of the subgrade construction.</p><p>　　130, soil and stone roadbed () engineering:</p><p>　　The quality inspection and acceptance of

37、1.4, check and acceptance: when should focus on the roadbed compaction, flatness, slope, roadbed width and deflection testing etc.</p><p>　　2 and roadbed construction process</p><p>　　The origin

38、al surface and 2.1, slope base</p><p>　　The quality of subgrade construction project is the key and route of roadbed project can withstand time, vehicle load, the winter monsoon rains. To make the subgrade e

39、ngineering, roadbed compactness.a work.we must, on the surface of in-situ and slope of base. roadbed compactness.a should first on the ground. When the road embankment height not less than 1.0 m, should pay attention to

40、the subgrade within the scope of the roots, grass all disadvantage. If the surface soil corrosion of basement, ne</p><p>　　With 2.2, subgrade soil compaction</p><p>　　Highway roadbed of strength

41、 and stability depends to a great extent on the nature and the roadbed compaction packing. From the present conditions, and improve soil compaction condition and roadbed quality guarantee is the most effective and econom

42、ical way.</p><p>　　Ammeters subgrade filling</p><p>　　The rules and regulations of subgrade filling should choose conditions. Rock embankment is an ideal material should be good stability, conve

43、nient construction, small compressibility compaction and the distance of the soil and stone material is short. Packing should be generally adopted gravel subgrade and plasticity index of soil moisture content and conform

44、ance to specifications, don't use silt, swamp, organic soil, frozen, grass, garbage and contain the soil corrosion. More than 50 for liquid </p><p>　　compaction soil base</p><p>　　Earth comp

45、action effect of soil compaction degree is to improve the permeability of soil, water, reducing the height of capillary, control water and soil erosion of concentration and softening, or because of the yankees and frost

46、heaving the non-uniform deformation</p><p>　　earth compaction theory</p><p>　　In most cases, by soil subgrade soil, water and air is composed of three-phase system. They all have their respectiv

47、e characteristics and interdependent common in a unity, constitute the physical characteristics of the soil, viscosity, permeability and elasticity, plasticity and mechanical strength, etc. If the situation changes, is c

48、omposed of soil physical properties to be different. Therefore, to change the characteristics of soil, and the change from the start. Soil compaction, is by mechani</p><p>　　Earth compaction effect of intern

49、al factors of soil moisture content and main is nature, external factors have compaction function, compaction methods and tools, etc.</p><p>　　1 compaction effect of moisture（1）water is the decisive factor o

50、f compaction effect,</p><p>　　2 when the optimum moisture in the soil, which is hard plastic state, the most easily get the best compaction effect,</p><p>　　3 the soil pressure ShiDao best densi

51、ty water stability.</p><p>　　For soil compaction effect</p><p>　　(1) the different soil types are different optimum moisture and maximum dry density,</p><p>　　2 higher (liquid-limi

52、t high dispersion viscosity, the soil, the larger), the absolute best content of absolute maximum dry density and lesser,</p><p>　　3 the sand and clay compaction of good performance (ρ > c 1.85) and cohes

53、ive soil compaction of poor performance (ρ < 1.70) c.</p><p>　　compaction of compaction effect function</p><p>　　The same kind of soil compaction function with the best content decreased, whi

54、le the maximum dry density function with the compaction increases, When the moisture content must, when the compaction function is higher density, When the compaction increases to a certain function, soil compaction degr

55、ee is not significantly increased, it shows that, for a certain kind of soil, if exceeds a certain extent, in which the compaction increases the way to improve soil compaction degree is not economical.</p><p&g

56、t;　　compaction tools and methods for compaction effect</p><p>　　(1) the compaction tools, how effective pressure transmission is different also. Research shows that, after the pressure of machines, vibration

57、-type transmission deepest, most shallow rolling type.</p><p>　　2 the compaction machine, load weight more hours long, soil compaction degree is higher, but the rate of growth of density decreases with incre

58、ase of time, compaction machine is heavier, soil compaction degree was increased with increasing unloading time quickly, but more than a time limit of soil deformation, destruction will increase sharply and achieve, Mach

59、ines that exceed the soil heavy intensity limit, will cause the soil.</p><p>　　3 the higher speed roller compaction effect.</p><p>　　Currently, generally USES the roadbed construction of large-t

60、onnage roller (less than), the road roller upward-leading continuous casting.the to center on both sides, until the surface of the wheel track without obvious, follow after the first light weight, low vibration, the firs

61、t after stability after the first slow, quick, high, the principle of the wheel, compaction effect of overlap has been improved. To improve the subgrade soil compaction degree on the good effect. Rules and regulations a&

62、lt;/p><p>　　special damp area of subgrade soil compaction</p><p>　　In special areas damp, the roadbed compaction is very difficult to make some adjustment standard: one is the degree of compaction

63、test data can be determined according to the standard list or lower numerical reduce 2-3 percentage points, Two is less than 1.1, natural consistency for more than 40 liquid-limit, plastic index of more than 18, when use

64、d in goo soil under the bed and road embankment packing, can adopt prescribed light compacted standards, Three is to improve the packing in soil prope</p><p>　　loess embankment filling and compaction</p&g

65、t;<p>　　.1 loess embankment construction, should make the combination fill &excavation interface (vertical), remove weeds, slope dug in the steps to tilt. As with vertical surfaces, unable to dig into the step

66、s, can be used to strengthen nails with geotextile. If the foundation soil with strong sex or higher collapsible bearing, and allow the compressibility than embankment self-respect, can consider to use heavy hammer, mat,

67、 laying geotextile between gravel pile and lime pile compacting reinforcement.</p><p>　　.2 loess moisture content is too small, should add uniform any rolling, If too much, can turn loose moisture content to

68、 air again, can also adding lime treatment, reduce moisture. After the ash content should be well, ash, the maximum dry density should be determined by the compaction test.</p><p>　　3 old loess, poor permeab

69、ility is wet, large soil crushed before use, not be decided by experiment. Road bed packing shall use the old loess. The new packing for the good of loess, can be used for filling road bed. The loess embankment should be

70、 layered rock, stratification, compaction, the block 10cm must be broken, and shall be in close on the compaction optimum moisture when rolling.</p><p>　　4 according to build on the edge of the lateral desig

71、n timely LanShui, cut ditch installations and rushing water trough, will lead to the slope of feet, the embankment height than 20m, should according to the design pressure after the completion of the reserve of embankmen

72、t sinking of dense consolidation is compressed.</p><p>　　loess areas should pay special attention to road surface drainage, interception, should adopt decentralized, seepage, far far sent up according to the

73、 design principle, timely to comprehensive drainage facilities, will quickly lead from water roadbed. Fill &excavation border drawn in the gutter, should make the outlet of the water.</p><p>　　and roadbe

74、d drainage</p><p>　　Water is the impact strength and stability of road embankment and the service life of another important factor, many roadbed disease is caused by water erosion and another, to protect the

75、 environment, does not damage from local irrigation and water conservancy facilities, also must prepare the roadbed drainage, drainage system, and coordinated with drainage planning. In subgrade construction, constructio

76、n drainage, should pay attention to prevent the floods caused by various subgrade pavement co</p><p>　　ground drainage</p><p>　　Most often by increasing the minimum height of filling roadbed and

77、 ground drainage facilities (ditches, cut ditch, the plunge, and the surface of the drain tank. For highway and level of drainage ditches on the highway, generally require slabs protection. Commonly used brick and reinfo

78、rced slurry crushed cement concrete prefabricated plate also started a wide range of applications. Highway and grade highway roadbed by dipping, past the location of every channel set contain in some places have im</p

79、><p>　　underground drainage</p><p>　　The underground drainage is multi-purpose AnGou roadbed, blind ditch, ShenGou, etc, its characteristic is shall, when water permeation drain, the more water pip

80、e ShenGou. The traditional gravel layer filter material to have filter function of geotextiles, years of development, the filter cloth with steel composed of synthetic fiber and strengthen stiffening fiberoptic permeable

81、 tube diameter 8-30cm, is applicable to the underground drainage.</p><p>　　and roadbed protection</p><p>　　The roadbed construction changed the natural balance, the formation and roadbed exposed

82、 constantly, space by various complicated natural factors, so need to erode all kinds of protection.</p><p>　　slope protection</p><p>　　Slope protection aims to prevent the surface water erosion

83、, the slope rock weathering spalling and environmental coordination. In recent years, with the importance of environmental protection, highway slope, use the grass slope protection, the higher QiShi box (square, diamond,

84、 arch type, M) grass protection. Due to the west slope protection to water, dry grass type selection is very important, are mostly using lawn, is born planting seed, fertilizer and soil evenly mixing with things, when th

85、e </p><p>　　Stone is widely used WuGong protection, prefabricated concrete block in the embankment slope protection multi-purpose, where the hole and HuMianQiang, Used for cutting slope. Broken or easy weath

86、ering broken rock bolting world.firstly adopts hanging barbed wire or spray or plastic mesh high-strength fiber shotcrete and injection coagulation in protective also have better effect.</p><p>　　But because

87、 WuGong stone and concrete protective cost is high, easy to damage such problems, from the Angle of environmental protection, suggestion promoting can improve ecological environment, landscaping, and once planted protect

88、ion.</p><p>　　erosion protection</p><p>　　River embankment slope protection is still used more directly from the scour protection. The traditional QiShi, stone, stone cage, wire etc, retaining w

89、all with improvement of high-strength geogrid instead of wire do with stone cage, polyester or polyurethane type geotextiles mold bag concrete slope made by the panel protection of water, surf soil slope can adapt to the

90、 uneven settlement.</p><p>　　4 retaining protection</p><p>　　Retaining wall used for retaining protection is still the main. Stone's gravity retaining wall for stone walls, high and low foun

91、dation good occasion, Reinforced concrete structure of cantilever retaining wall, retaining wall and wall of retaining the column is reasonable, wall body WuGong small volume, has been widely used in highway roadbed prot

92、ection. Enclosed earth-retaining wall to adjust the height of the wall, and the prefabricated component assembles, is a special type of retaining wall.</p><p>　　5 soft foundation treatment</p><p&g

93、t;　　In recent years, with the highway and level of highway construction, according to the rapid development of soft soil foundation, prevent loss of embankment settlement observational control, stable, soft soil subgrade

94、 treatment technology achieved significant results. To deal with the soft soil foundation with sedimentation rate as paving surface subsidence control method to control the time in soft soil foundation, the senior paveme

95、nt (not completed the transition of pavement done.the key techni</p><p>　　lime-soil compaction pile</p><p>　　When the content of soft soil layer, take too much or too hours lime-soil compaction

96、pile.</p><p>　　Excessive moisture content can fill in dry soil into holes or lime powder, powder to absorb moisture, or rapid part water hole hole side or under casing hole, or after casing, Moisture content

97、 is too small, should be soaked in advance within the scope of reinforcement layer and should be formed after the order, the circle and intervals, Already, should prevent hole by soaking water, and shall be days backfill

98、ing ramming, In order to avoid causing shrinkage ramming dozen cold, should play carotid</p><p>　　Certainly, lightweight embankment</p><p>　　Use of lightweight materials can reduce the embankmen

99、t of embankment foundation bearing capacity requirements. Currently China has applied the successful experience of fly ash filling embankment, can make the embankment self-respect reduce 25%. With heavy compaction test m

100、ethod for the determination of dry density is 9-12KN/m3. Silicon ash viscous drilling type, plastic, but not around 64% in liquid limit, the optimum moisture 37-41, have good compaction performance. Fly ash embankment sl