反fan射she裂lie縫feng是shi瀝li青qing路lu麵mian普pu遍bian存cun在zai的de一yi種zhong病bing害hai現xian象xiang。根gen據ju國guo內nei外wai道dao路lu工gong程cheng的de實shi踐jian,在zai瀝li青qing麵mian層ceng和he中zhong集ji瀝li青qing混hun合he料liao層ceng或huo粗cu集ji瀝li青qing混hun合he料liao層ceng之zhi間jian鋪pu設she一yi層ceng土tu工gong織zhi物wu,可ke用yong以yi消xiao除chu或huo減jian緩huan麵mian層ceng反fan射she裂lie縫feng的de產chan生sheng,從cong而er延yan長chang道dao路lu的de使shi用yong壽shou命ming,降jiang低di維wei修xiu成cheng本ben。但dan是shi,由you於yu瀝li青qing路lu麵mian澆jiao注zhu時shi的de溫wen度du高gao達da160℃-180℃,致使土工織物褶皺、變形、ruanhua,shiqixingnengdadajiangdi,budannanyixiaochuhuojianhuanmiancengfansheliefengdechansheng,erqieshideliqinglumiangengjiaaotubuping,erboxiantugonggezhasuoteyoudexingneng,wanquanmanzuliqinglumiandeyaoqiu,muqianxuduogongchengyishiyongboxiantugonggezha。
玻纖應用於瀝青道路時,可在以下幾方麵發揮作用。
(1)抗疲勞開裂
liqinglumianbixujuyouyidingdechengzainengli,zaiguidingdeshijianneibunengfashengpilaopohuai。liqinglumianzaizhijieyuchelunjiechudexiamiancengshoudaoyali,zailunzaibianyuanyiwaidequyu,miancengshoudaolalizuoyong,youyuliangchushouliquyusuoshoulixingzhibutong,eryoubicijinkao,yincizailiangkuaishouliquyudejiaojiechujilidetubianchufashengpohuai,zaichangqihezaidezuoyongxia,fashengpilaokailie。
boxiantugonggezhazailiqingmiancengzhong,nenggoujiangshangshudeyayingliyulayinglifensan,zailiangkuaishouliquyuzhijianxingchenghuanchongdai,jianshaoleyinglitubianduiliqingmiancengdepohuai。tongshibolixianweitugonggezhadediyanshenlvjianshaolelumiandewanchenliang,baozhenglelumianbuhuifashengguodubianxing。
(2) 耐高溫車轍
瀝(li)青(qing)混(hun)凝(ning)土(tu)在(zai)高(gao)溫(wen)時(shi)具(ju)有(you)流(liu)變(bian)性(xing),在(zai)車(che)輛(liang)荷(he)載(zai)作(zuo)用(yong)下(xia),受(shou)力(li)區(qu)域(yu)產(chan)生(sheng)凹(ao)陷(xian),車(che)輛(liang)荷(he)載(zai)撤(che)除(chu)後(hou),瀝(li)青(qing)麵(mian)層(ceng)無(wu)法(fa)完(wan)全(quan)恢(hui)複(fu)原(yuan)狀(zhuang)態(tai),即(ji)產(chan)生(sheng)了(le)塑(su)性(xing)變(bian)形(xing),在(zai)車(che)輛(liang)反(fan)複(fu)碾(nian)壓(ya)的(de)作(zuo)用(yong)下(xia),塑(su)性(xing)變(bian)形(xing)不(bu)斷(duan)積(ji)累(lei),形(xing)成(cheng)車(che)轍(zhe)。通(tong)過(guo)瀝(li)青(qing)麵(mian)層(ceng)結(jie)構(gou)分(fen)析(xi)可(ke)知(zhi),高(gao)溫(wen)下(xia)的(de)瀝(li)青(qing)混(hun)凝(ning)土(tu)在(zai)受(shou)到(dao)荷(he)載(zai)的(de)碾(nian)壓(ya)作(zuo)用(yong),形(xing)成(cheng)了(le)微(wei)量(liang)的(de)波(bo)形(xing)流(liu)變(bian),麵(mian)層(ceng)中(zhong)沒(mei)有(you)任(ren)何(he)可(ke)以(yi)約(yue)束(shu)瀝(li)青(qing)混(hun)凝(ning)土(tu)流(liu)變(bian)的(de)骨(gu)架(jia)材(cai)料(liao),造(zao)成(cheng)瀝(li)青(qing)麵(mian)層(ceng)流(liu)變(bian)的(de)累(lei)積(ji)疊(die)加(jia),這(zhe)是(shi)形(xing)成(cheng)車(che)轍(zhe)的(de)根(gen)本(ben)所(suo)在(zai)。
在zai瀝li青qing麵mian層ceng中zhong使shi用yong玻bo纖xian土tu工gong格ge柵zha,其qi在zai瀝li青qing麵mian層ceng中zhong起qi到dao骨gu架jia作zuo用yong,瀝li青qing砼tong中zhong集ji料liao貫guan穿chuan於yu格ge柵zha間jian,形xing成cheng複fu合he力li學xue嵌qian鎖suo體ti係xi,限xian製zhi集ji料liao運yun動dong,增zeng加jia了le瀝li青qing麵mian層ceng中zhong的de橫heng向xiang約yue束shu力li,瀝li青qing麵mian層ceng中zhong各ge部bu分fen彼bi此ci牽qian製zhi,防fang止zhi了le瀝li青qing麵mian層ceng的de推tui移yi,從cong而er起qi到dao抵di抗kang車che轍zhe的de作zuo用yong。
(3) 抗低溫縮裂
嚴yan寒han時shi期qi,瀝li青qing混hun凝ning土tu麵mian層ceng的de溫wen度du近jin於yu氣qi溫wen,瀝li青qing砼tong遇yu冷leng收shou縮suo,產chan生sheng拉la應ying力li,在zai受shou到dao荷he載zai反fan複fu作zuo用yong下xia,拉la應ying力li進jin一yi步bu增zeng加jia,當dang拉la應ying力li超chao過guo瀝li青qing砼tong拉la伸shen強qiang度du時shi,產chan生sheng裂lie紋wen,在zai裂lie紋wen兩liang端duan處chu,拉la應ying力li更geng加jia集ji中zhong,裂lie紋wen逐zhu步bu形xing成cheng裂lie縫feng,造zao成cheng病bing害hai。
玻(bo)纖(xian)土(tu)工(gong)格(ge)柵(zha)置(zhi)於(yu)瀝(li)青(qing)中(zhong),使(shi)得(de)瀝(li)青(qing)砼(tong)的(de)拉(la)伸(shen)強(qiang)度(du)大(da)大(da)提(ti)高(gao),足(zu)夠(gou)抵(di)抗(kang)住(zhu)較(jiao)大(da)的(de)拉(la)應(ying)力(li)而(er)不(bu)致(zhi)發(fa)生(sheng)路(lu)麵(mian)破(po)壞(huai),即(ji)使(shi)因(yin)為(wei)局(ju)部(bu)區(qu)域(yu)產(chan)生(sheng)微(wei)小(xiao)裂(lie)紋(wen),裂(lie)紋(wen)處(chu)的(de)應(ying)力(li)集(ji)中(zhong),經(jing)玻(bo)纖(xian)土(tu)工(gong)格(ge)柵(zha)的(de)傳(chuan)遞(di)而(er)消(xiao)失(shi),裂(lie)紋(wen)不(bu)會(hui)發(fa)展(zhan)成(cheng)裂(lie)縫(feng)。
(4) 延緩反射裂縫
裂lie縫feng產chan生sheng的de反fan射she有you兩liang種zhong,一yi種zhong是shi麵mian層ceng產chan生sheng裂lie縫feng後hou,裂lie縫feng向xiang下xia反fan射she,破po壞huai下xia層ceng結jie構gou,降jiang低di路lu麵mian結jie構gou強qiang度du,在zai雨yu水shui時shi節jie,水shui進jin入ru裂lie縫feng中zhong,在zai交jiao通tong荷he載zai(輪胎壓力)的(de)反(fan)複(fu)抵(di)壓(ya),水(shui)在(zai)裂(lie)縫(feng)中(zhong)產(chan)生(sheng)水(shui)壓(ya),水(shui)不(bu)斷(duan)的(de)衝(chong)擊(ji)瀝(li)青(qing)混(hun)合(he)料(liao),導(dao)致(zhi)裂(lie)縫(feng)擴(kuo)大(da)。另(ling)一(yi)種(zhong)是(shi)舊(jiu)麵(mian)層(ceng)原(yuan)有(you)裂(lie)縫(feng),路(lu)基(ji)層(ceng)或(huo)下(xia)層(ceng)路(lu)基(ji)層(ceng)產(chan)生(sheng)的(de)裂(lie)縫(feng)向(xiang)上(shang)反(fan)射(she),新(xin)罩(zhao)路(lu)麵(mian)無(wu)法(fa)承(cheng)受(shou)因(yin)底(di)層(ceng)移(yi)動(dong)而(er)產(chan)生(sheng)的(de)剪(jian)切(qie)力(li)和(he)抗(kang)伸(shen)應(ying)力(li),導(dao)致(zhi)路(lu)麵(mian)麵(mian)層(ceng)裂(lie)縫(feng)。
在瀝青罩麵層中加鋪玻纖土工格柵夾層,抑製應力,釋放應變,增強瀝青混凝土整體強度,達到防止裂縫向上或向下反射的目的。
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