【正文】
層 次: 專科起點本科 專 業(yè): 土木工程 年 級: 春 季 學 號: 學 生: 指導教師: 完成日期: 2015年 3月4日 III大連理工大學網(wǎng)絡教育學院畢業(yè)論文(設計)模板 摘要屋面漏水是建筑工程中存在的質(zhì)量通病,也是多年來一直未能很好解決的難題。關(guān)鍵詞:屋面防水;防水材料;防水施工;柔性防水;剛性防水目 錄內(nèi)容摘要 I引 言 III1 建筑防水概述 1 建筑防水的種類 1 建筑防水的重要性 12 屋面防水質(zhì)量的影響因素和控制 2 屋面防水質(zhì)量的影響因素 2 設計方面 2 防水材料的選擇 2 防水工程造價及施工質(zhì)量的保證 2 屋面使用不當 2 屋面防水質(zhì)量的控制 2 屋面防水的施工方法 2 屋面防水主要施工技術(shù)要點 3 屋面防水工程質(zhì)量控制要點 43 剛性防水屋面 5 剛性防水屋面的特點 5 剛性防水屋面的施工技術(shù)要點 5 剛性防水屋面的質(zhì)量控制 84 柔性防水屋面 10 柔性防水屋面的特點 10 柔性防水屋面的施工技術(shù)要點 10 柔性防水屋面的質(zhì)量控制 115 常見的技術(shù)問題及解決辦法 136 結(jié)論與展望 16參考文獻 17引 言建筑屋面防水質(zhì)量的低劣是造成滲漏的最直接原因,影響滲漏的因素是多方面的,在施工中人們往往在選材、設計、管理維護造成忽略,以至給工程質(zhì)量留下后期隱患。卷材防水是用瀝青和適量粉料加熱調(diào)制成熱瀝青膏膠結(jié)料,將油氈(見防水卷材)分層鋪貼于屋面、地下建筑、儲水構(gòu)筑物的內(nèi)外表面。因此,在進行建筑防水設計時,一定不能忽視外墻的防水設計。一個好的屋面排水設計應該做到排水坡度合力,落水管充足,排防結(jié)合,能夠迅速把雨水排走;反之,排水不暢就會造成屋面長期處于積水狀態(tài),這是屋面滲漏的一個根源。分格縫的設置間距不宜過大,當大于6m時,應在中部設一“v”形分格縫,分格縫深度宜貫穿整個防水層厚度。混凝土的厚度不應小于40mm。(3)屋面防水施工控制防水基層要抹平壓光,不允許有凹凸不平、松動和起砂掉灰等缺陷存在。另外,防水層所用的材料必須有出廠合格證書和試驗報告單,同時在現(xiàn)場使用前必須再做復檢,合格后方可使用。3 剛性防水屋面 剛性防水屋面的特點剛性防水屋面具有施工簡便、造價較低、防水性能良好等特點。 (2)做隔離層 1)在細石混凝土防水層與基層之間設置隔離層,依據(jù)設計可采用于鋪無紡布、塑料薄膜或者低強度等級的砂漿,施工時避免鋼筋破壞防水層,必要時可在防水層上做砂漿保護層。 4)為便于拆除,分格縫鑲嵌材料也可以使用聚苯板或定型聚氯乙烯塑料分格條,底部用水泥砂漿固定在彈線位置。 2)待混凝土收水初凝后,大約10h左右,起出木條,避免破壞分格縫,用鐵抹子進行第一次抹壓,混凝土終凝前進行第二次抹壓,使混凝土表面平整、光滑、無抹痕。 2)嵌填密封材料 ①應先對分格縫、變形縫等防水部位的基層進行修補清理,去除灰塵雜物。~,接縫處的底部應填放與基層處理劑不相容的背襯材料,如泡沫棒或油氈條。 剛性防水屋面的質(zhì)量控制1.改善混凝土級配保證混凝土的施工質(zhì)量 剛性防水屋面混凝土的強度等級不宜低于C20,水泥品種應按設計要求和季節(jié)選用,當有抗凍要求時,應優(yōu)先選用硅酸鹽水泥,水泥最小用量汪得少于330kg/m3。近年來,還有混凝土中摻入鋼釬維或聚丙烯纖維來提高混凝土的抗裂能力,鋼纖維可以與混凝土充分混合,分散性好,對防止混凝土的開裂起到重要作用。石灰砂漿配合比為石灰膏:砂=1:4;,鋪前先濕潤基層,鋪抹厚度為10~20mm,表面平整,壓實,抹光后養(yǎng)護至基本干燥。 柔性防水屋面的主要優(yōu)點是它對房屋地基沉降、房屋受振動或溫度影響的適應性較好,防止?jié)B漏水的質(zhì)量比較穩(wěn)定。為出水口,八一入為起脊、八一8或8—8為分水脊。 (三)操作及質(zhì)量要求: 墻面清凈,刷107膠水,提高墻面強度。 施工工藝和方法對防水層的施工質(zhì)量影響也很大,若卷材是通過熬燒粘結(jié)劑與基層粘貼的,在地面熱熔的粘結(jié)劑,通過小桶拎到屋面,然后再一點點攤鋪,粘結(jié)劑的熱量散發(fā)很大,卷材鋪壓時粘結(jié)劑的溫度已達不到要求,防水層的粘貼效果降低。(三)加強細部構(gòu)造質(zhì)量控制 屋面變形縫、后澆帶、穿墻管、女兒墻體、雨水口等與底板接板接茌處是容易造成屋面滲漏的重要部位。所以使用前還應送到試驗室進行復試,合格后方可使用。導致水泥砂漿找平層開裂的主要原因有: 1.保溫層鋪墊不平不實,造成攏干層厚薄不勻,干縮不一致。這樣避免施工后留下缺陷,造成返工,同時工程依據(jù)施工組織有計劃地展開施工,防止工作遺漏、錯亂、顛倒影響工程質(zhì)量。水落口周圍直徑500mm范圍內(nèi)坡度不應小于5%,水落管徑不應小于75mm,一根水落管的屋面最大匯水面積宜小于200m2。 2.細部構(gòu)造復雜部位處理。排除空氣后,平面部位可用外包橡膠的長300mm、重30kg的鐵輥滾壓,使卷材與基層粘結(jié)牢固。當然,減少乃至根治建筑屋面的滲漏問題,還需改正施工技術(shù)管理水平等諸多不合理之處,提高設計及施工人員的從業(yè)水平,從多方面提高人們對屋面防水重要性的認識程度,從原材料、設計、施工的各個環(huán)節(jié)進行把關(guān),才能從根本上解決滲漏問題,當然這還有一段很長的路要走。s gross ine to arrive at an adjusted gross ine, from which additional deductions are taken to arrive at the taxable ine. Once the amount of taxable ine has been determined, tax rate charts determine the exact amount of tax owed. If the amount of tax owed is less than the amount already paid through tax prepayment or the withholding of taxes from paychecks, the taxpayer is entitled to a refund from the IRS. If the amount of tax owed is more than what has already been paid, the taxpayer must pay the difference to the IRS. Calculating the gross ine of restaurant employees whose ine is partially derived from gratuities left by customers has led to disputes with the IRS and employers over how much they should contribute in federal insurance contribution act (fica) taxes. Although customers pay these tips directly to employees, federal law deems the tips to have been wages paid by the employer for FICA tax purposes. Employers are imputed to have paid large sums of money they never handled and for which they no way of ascertaining the exact amount. The Supreme Court, ins new deal, imposed a five percent excise tax on dividend receipts, imposed a capital stock tax and an excess profits tax, and suspended all deductions for losses (June 16, 1933, ch. 90, 48 Stat. 195). The repeal in 1933 of the eighteenth amendment, which had prohibited the manufacture and sale of alcohol, brought in an estimated $90 million in new liquor taxes in 1934. The social security act of 1935 provided for a wage tax, half to be paid by the employee and half by the employer, to establish a federal retirement fund (Old Age Pension Act, Aug. 14, 1935, ch. 531, 49 Stat. 620). The Wealth Tax Act, also known as the Revenue Act of 1935, increased the maximum tax rate to 79 percent, the Revenue Acts of 1940 and 1941 increased it to 81 percent, the Revenue Act of 1942 raised it to 88 percent, and the Individual Ine Tax Act of 1944 raised the individual maximum rate to 94 percent. The postWorld War II Revenue Act of 1945 reduced the individual maximum tax from 94 percent to 91 percent. The Revenue Act of 1950, during the korean war, reduced it to percent, but it was raised the next year to 92 percent (Revenue Act of 1950, Sept. 23, 1950, ch. 994, Stat. 906). It remained at this level until 1964, when it was reduced to 70 percent. The Revenue Act of 1954 revised the Internal Revenue Code of 1939, making major changes that were beneficial to the taxpayer, including providing for child care deductions (later