[關(guān)鍵詞] 巖棉;外墻外保溫
[中圖分類號] TU55+1.3 [文獻(xiàn)標(biāo)識碼] A
Application and Study on Outer-wall External Thermal Insulation based on Rock-wool
SONG Chang-you1,CHEN Dan-lin3,LIN Yan-cheng1, HUANG Zhen-li1
(1.Beijing Zhenli High New Technology Co., Ltd., Beijing 100073,China;2.Beijing Liujian Construction Corporation, Beijing 100039,China)
[Abstract] The paper introduced the applied technology of rock-wool in outer-wall external thermal insulation. These applied technologies were the key content in the proposal of “study on fire-proof technology of outer-wall external thermal insulation for high-rise building” which belongs to Beijing Science Committee. The study provided 2 kinds of finish systems which were pouring and anchoring rock-wool panel respectively. In general, galvanizing steel-meshwork using machine anchor can use all kinds of Rock-wool panel made in China. The interface mortar used in Rock-wool can prevent worker’s hand from hurting and improve the water-proof capability and bonding intensity of rock-wool panel. The low-heat conductivity of polystyrene foaming granule paste improved the integer and anti-crack of system. The 2 kinds of rock-wool system all can resolve the current rock-wool panel applied difficulty in outer-wall external thermal insulation. The rock-wool external thermal insulation which has very nice fire-proof capability can apply any kinds of builds, especially high-rise buildings.
[Keywords] rock-wool,outer-wall external thermal insulation
1 巖棉的定義、巖棉板的類型與特點
巖棉在20世紀(jì)30年代就已投入工業(yè)化生產(chǎn),是目前世界上應(yīng)用范圍最廣的保溫材料。在國外巖棉被稱為“第五常規(guī)能源”,此種材料在建筑中的應(yīng)用最為廣泛。
1.1巖棉的定義
在我國的標(biāo)準(zhǔn)中對巖棉(Rock-wool)是這樣定義的:主要由熔融天然火成巖制成的一種礦物棉稱為巖棉。巖棉是以精選的玄武巖或輝綠巖為主要原料,外加一定數(shù)量的補(bǔ)助料,經(jīng)高溫熔融離心吹制成人造無機(jī)纖維,其主要化學(xué)成分為:SiO2(46%)、Al2O3(15.6%)、MgO(5.1%)、CaO(28%)、Fe2O3(3.3%)。
1.2巖棉板的類型與特點
在巖棉纖維中加入適量粘結(jié)劑、防塵劑、憎水劑等外加劑,經(jīng)過壓制固化可制成具有一定強(qiáng)度的巖棉板。根據(jù)目前的生產(chǎn)工藝,可分為沉降法巖棉板、擺錘法巖棉板和三維法巖棉板。
1)沉降法工藝的主要生產(chǎn)流程是高溫熔體經(jīng)離心吹制,形成巖棉纖維,在沉降室的輸送帶上堆積,達(dá)到一定厚度以后,經(jīng)過加壓輥進(jìn)入固化爐,沉降室法巖棉的纖維為平面分布,密度和粘結(jié)劑的均勻性較差,影響板的抗壓性能和層間結(jié)合強(qiáng)度。
2)擺錘法是在沉降法的基礎(chǔ)上,通過改進(jìn)收棉方法,先由捕集帶收集較薄的巖棉層,經(jīng)擺錘的逐層疊鋪,達(dá)到一定的層數(shù)和厚度,再由加壓輥進(jìn)行壓制,進(jìn)入固化爐固化,再經(jīng)冷卻、切割、包裝等工序制成成品。這種方法改善了棉層及所含的粘結(jié)劑的均勻程度,并且由于棉層疊鋪時產(chǎn)生的斜度,纖維呈部分豎向分布,因而抗壓強(qiáng)度和層間結(jié)合強(qiáng)度得到提高。
3)三維法巖棉是把擺錘法疊鋪形成的未固化巖棉層,通過機(jī)械方法改變棉層的分布方向,從而形成高強(qiáng)度的三維巖棉產(chǎn)品,三維法巖棉纖維呈三維分布,抗壓強(qiáng)度高,不易分層和剝離。
通過這3種方法生產(chǎn)出來的巖棉板在物理性質(zhì)上有較大的差別,沉降法巖棉板基本上沒有抗剝離強(qiáng)度,而擺錘法巖棉板的抗剝離強(qiáng)度大于14 kPa,三維法巖棉板的抗剝離強(qiáng)度大于22 kPa;10%壓縮量的壓縮強(qiáng)度沉降法巖棉板不到20 kPa,而擺錘法巖棉板可達(dá)40 kPa以上,三維法巖棉板則可達(dá)到60 kPa以上;采用完全浸入法測定巖棉板的吸水性,沉降法巖棉板的吸水量是其自身重量的幾十倍,而且吸入的水分在十幾天過后也不能完全排除,擺錘法巖棉板的吸水量比較小,是其自身重量的幾倍,三維法巖棉板的吸水性與聚苯板