護(hù)欄網(wǎng)發(fā)展史
隨著國內(nèi)高速公路建設(shè)的飛速發(fā)展，安全護(hù)欄市場不斷擴(kuò)大，但由于該產(chǎn)品在我國的生產(chǎn)和使用時(shí)間不足十年，產(chǎn)品標(biāo)準(zhǔn)頒布僅
五六年，國家標(biāo)準(zhǔn)頒布剛兩年，生產(chǎn)廠家對(duì)該產(chǎn)品的性能、技術(shù)參數(shù)、生產(chǎn)工藝掌握各不相同，致使這一產(chǎn)品的質(zhì)量良莠不齊。有的
路段由于采用了防腐工藝處理不當(dāng)?shù)淖o(hù)欄產(chǎn)品，少則一兩年時(shí)間，護(hù)欄便銹跡斑斑，不僅影響了高速公路的視覺效果，也大大縮短了
護(hù)欄的有效使用期，同時(shí)也增加了維護(hù)成本。
我國早期通常采用涂漆防護(hù)，后來逐步采用熱浸鋅的形式，仍大量廣泛采用熱浸鋅方式防護(hù)。護(hù)欄屬于戶外使用的大型長久性設(shè)
施，對(duì)防護(hù)體系的選擇要針對(duì)不同的大氣環(huán)境選擇不同的防護(hù)體系。新頒布的國家標(biāo)準(zhǔn)GB/T18226-2000 《高速公路交通工程鋼構(gòu)件防
腐技術(shù)條件》，將護(hù)欄產(chǎn)品的防護(hù)分為四類：鍍鋅、鍍鋁、鍍鋅（鋁）后涂塑、涂塑。在鄉(xiāng)村和污染不嚴(yán)重的地區(qū)，可采用單獨(dú)熱浸鋅
層防護(hù)或單獨(dú)噴塑防護(hù)型護(hù)欄板，而在重工業(yè)區(qū)或海岸城市地區(qū)，特別是有酸雨的地區(qū)，普通熱浸鋅或噴塑單涂層護(hù)欄板未到使用年限
就可能失去效用，造成護(hù)欄的維護(hù)成本大大增加。對(duì)于熱浸鋁護(hù)欄，其耐蝕性比普通熱浸鋅護(hù)欄好，但其工藝、技術(shù)、成本以及對(duì)環(huán)境
影響等方面的原因，應(yīng)用范圍還不很廣。而采用熱浸鋁+噴塑的防護(hù)體系，相對(duì)于熱浸鋅+噴塑的防護(hù)體系是一種不經(jīng)濟(jì)的方法。采用鍍
鋅板+噴塑的雙防護(hù)體系，可在重污染地區(qū)特別是酸雨地區(qū)達(dá)到較好的防腐效果，使用年限大大延長，最耐久的防護(hù)方法。
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Can you be more specific about the content of your article? After reading it, I still have some doubts. Hope you can help me.
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