[摘 要] 通過介紹混凝土專用聚丙烯纖維的研究與發展情況及國外對聚丙烯纖維用於混凝土規範,了解聚丙烯纖維工作機理和工程設計要求。 [關鍵詞] 纖維混凝土 聚丙烯纖維 增強型 外摻料型 纖維網 1.前 提 纖維在提高混凝土性能方麵扮演著日益重要的角色。混凝土的發展已有100多duo年nian曆li史shi,高gao強qiang化hua在zai很hen長chang時shi間jian裏li是shi努nu力li的de目mu標biao,被bei認ren為wei是shi優you質zhi混hun凝ning土tu的de特te征zheng。但dan是shi混hun凝ning土tu是shi一yi種zhong脆cui性xing材cai料liao,韌ren性xing差cha,抗kang疲pi勞lao能neng力li低di,易yi產chan生sheng裂lie紋wen,抗kang衝chong擊ji碎sui裂lie性xing差cha,這zhe種zhong問wen題ti不bu是shi因yin為wei強qiang度du不bu夠gou,而er是shi耐nai久jiu性xing不bu夠gou。多duo年nian來lai,工gong程cheng技ji術shu人ren員yuan從cong原yuan材cai料liao、配合比、外加劑、製造工藝、養護工藝等多方麵加以研究改進,雖取得了一些成效但不理想,因此,混凝土的高性能化才是解決問題的關鍵。 中國工程院院士吳中偉教授認為:複合化是水泥基材料高性能化的主要途徑,纖維增強是其核心。自70年代,纖維增強水泥複合材料發展起來,鋼纖維、玻璃纖維已較早地應用於混凝土,可以從多方麵改善混凝土的性能,關於鋼纖維、玻璃纖維應用領域和使用情況已趨於明確,我國於1992nianbanbulegangxianweideshejishiyongbiaozhunguifan。suizhecailiaojiagongjishudejinbu,zhuanyongyuhunningtudejubingxixianweiyanzhichenggong,shixianweihunningtujishujinruyigexindejieduan。 2.纖維混凝土 纖xian維wei混hun凝ning土tu就jiu是shi在zai混hun凝ning土tu拌ban合he過guo程cheng中zhong加jia入ru一yi定ding量liang的de纖xian維wei材cai料liao,通tong過guo纖xian維wei的de密mi集ji分fen布bu來lai提ti高gao混hun凝ning土tu的de性xing能neng。在zai民min間jian,很hen早zao就jiu把ba麥mai稈gan剁duo碎sui或huo用yong切qie斷duan的de發fa絲si拌ban入ru泥ni漿jiang中zhong,建jian造zao土tu坯pi或huo擋dang牆qiang,獲huo得de阻zu裂lie的de效xiao果guo。纖xian維wei混hun凝ning土tu的de機ji理li與yu其qi有you一yi定ding的de接jie近jin,纖xian維wei對dui混hun凝ning土tu的de貢gong獻xian是shi從cong抑yi製zhi塑su性xing開kai裂lie開kai始shi的de。而er纖xian維wei對dui混hun凝ning土tu性xing能neng的de提ti高gao,必bi須xu具ju備bei以yi下xia幾ji個ge主zhu要yao條tiao件jian: (1) 分布均勻 (2) 與混凝土的握裹性強 (3) 材料本身抗腐蝕、抗堿集料反應強 (4)材質的抗拉強度好 zhesigetiaojianmeigedoushizhongyaohebibukeshaode。xuyaoshuomingdeshi,xianweiduihunningtudezuoyongbushiweitigaoqiangdu,ershitongguodadaoshangshudetiaojian,laitigaohunningtudekanglie、抗碎、抗滲水、抗折、抗衝擊、抗疲勞等綜合性能。鋼纖維與合成纖維都對混凝土強度有提高,因材質不同鋼纖維提高的要大。 gangxianweishizuizaoyingyongyuhunningtude,zheziranyuanyugangjinhunningtudeqifa,suizhexianweihunningtujishudefazhande,renmenbayanjiuzhongdianqingxiangyuhechengxianwei,hechengxianweichengbendi,dangzaihunningtuzhongjunyunfenbuhou,nengtigonggenghaoderenxing。hunningtushiyingxingcailiao,hechengxianweishiruanxingcailiao,zhezhonggangrouxiangjidebanfanengtigaohunningtujianrenxing。zaihechengxianweizhongjubingxishizuihaodecailiao,naifushi、抗堿反應。 3.用於混凝土的聚丙烯纖維 早在70niandai,yingguoxibuhaiandejiagugongchengzhong,gongchengrenyuanbaqiesuidejubingxichanrudaohunningtuzhong,yonglaiqichengfanghudi。xuduogongchengjishurenyuandouzaijinxingjubingxixianweiyongyuhunningtudeyanjiu。nashideshiyanjieguohuoxianghumaodunhuobulixiang,zhexieshiyanjieguoyizhibeizuoweipingdingjubingxixianweidejichu。renmenyizhirenweijubingxiwufaduihunningtuchanshengxiaoguo,erqiezhexiegulvxianzaiyirancunzai,zheshihenbuxingde。yinweinaxieshiyansuoshiyongdejubingxixianwei,yaomeshijubingxifeipinhuishouhouzhicheng,yaomeshicongfangzhiyezhongjieyongde,zaizhejiushiyongjianduandebaozhuangdai、shengzidaiti,zhexiecailiaogenbenwufajiejueshangshuxianweihunningtudesigeyaodian,youyucunzaixianweibenshendechanrao,zaibanruhunningtuzhongyijietuan,suoyiguanyujubingxishifoukeyongyuhunningtuyizhicunzaizhengyi。 80niandaichuqi,meiguojunduigongchengshidehunningtuzhuanjiaweijiejuejunyonghunningtugongshizaishoupaohuogongjihoudekangsuiwenti,tongshiyeweijiejuejunshigongchengdenaijiuxingwenti,tamenceshiyanjiulehenduozhongcailiaohefangfa。zuihouqueren,zaihunningtuzhongjiaruyidingliangdejubingxixianweixiaoguozuihao,yushihunningtuzhuanjiayumeiguozuidadehuagongchanpinqiye──合成工業公司的聚丙烯材料專家共同研製用於混凝土的專用纖維,並於1984年成功研製出混凝土聚丙烯纖維──“FIBERMESH”,中文譯為“纖維網”。這是世界第一種成功用於混凝土增強的聚丙烯纖維。 3.1纖維網 纖(xian)維(wei)網(wang)一(yi)種(zhong)網(wang)狀(zhuang)結(jie)構(gou)的(de)聚(ju)丙(bing)烯(xi)纖(xian)維(wei)束(shu),由(you)美(mei)國(guo)纖(xian)維(wei)網(wang)砼(tong)公(gong)司(si)及(ji)其(qi)國(guo)際(ji)代(dai)理(li)機(ji)構(gou)擁(yong)有(you)專(zhuan)利(li)。它(ta)從(cong)各(ge)個(ge)角(jiao)度(du)解(jie)決(jue)了(le)聚(ju)丙(bing)烯(xi)纖(xian)維(wei)用(yong)於(yu)混(hun)凝(ning)土(tu)所(suo)遇(yu)到(dao)的(de)問(wen)題(ti): (1) 集束形網狀結構在混凝土中拌和時先呈束狀大麵積分布,攪拌中期每束中的5-8個小束纖維分離出來,受骨料衝擊後展開成網狀,並隨著攪拌衝擊被撕開成不規則單絲,達到均勻分布的目的。這種被稱之為“二次分布法”的均勻分布方式與某種同樣可均勻分布的釘書針式排狀鋼纖維是一個原理。完全解決了分布均勻的問題。 (2) 與yu混hun凝ning土tu的de握wo裹guo性xing問wen題ti,鋼gang纖xian維wei以yi做zuo成cheng波bo浪lang狀zhuang或huo兩liang關guan弓gong形xing來lai解jie決jue握wo裹guo性xing問wen題ti,在zai合he成cheng類lei纖xian維wei中zhong,有you多duo種zhong單dan絲si纖xian維wei截jie麵mian成cheng圓yuan形xing,纖xian維wei絲si麵mian光guang滑hua,無wu法fa達da到dao良liang好hao的de握wo裹guo性xing。纖xian維wei網wang在zai拌ban和he時shi撕si裂lie成cheng絲si, |