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(da)160℃-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
瀝li青qing路lu麵mian必bi須xu具ju有you一yi定ding的de承cheng載zai能neng力li,在zai規gui定ding的de時shi間jian內nei不bu能neng發fa生sheng疲pi勞lao破po壞huai。瀝li青qing路lu麵mian在zai直zhi接jie與yu車che輪lun接jie觸chu的de下xia麵mian層ceng受shou到dao壓ya力li,在zai輪lun載zai邊bian緣yuan以yi外wai的de區qu域yu,麵mian層ceng受shou到dao拉la力li作zuo用yong,由you於yu兩liang處chu受shou力li區qu域yu所suo受shou力li性xing質zhi不bu同tong,而er又you彼bi此ci緊jin靠kao,因yin此ci在zai兩liang塊kuai受shou力li區qu域yu的de交jiao界jie處chu即ji力li的de突tu變bian處chu發fa生sheng破po壞huai,在zai長chang期qi荷he載zai的de作zuo用yong下xia,發fa生sheng疲pi勞lao開kai裂lie。
玻(bo)纖(xian)土(tu)工(gong)格(ge)柵(zha)在(zai)瀝(li)青(qing)麵(mian)層(ceng)中(zhong),能(neng)夠(gou)將(jiang)上(shang)述(shu)的(de)壓(ya)應(ying)力(li)與(yu)拉(la)應(ying)力(li)分(fen)散(san),在(zai)兩(liang)塊(kuai)受(shou)力(li)區(qu)域(yu)之(zhi)間(jian)形(xing)成(cheng)緩(huan)衝(chong)帶(dai),減(jian)少(shao)了(le)應(ying)力(li)突(tu)變(bian)對(dui)瀝(li)青(qing)麵(mian)層(ceng)的(de)破(po)壞(huai)。同(tong)時(shi)玻(bo)璃(li)纖(xian)維(wei)土(tu)工(gong)格(ge)柵(zha)的(de)低(di)延(yan)伸(shen)率(lv)減(jian)少(shao)了(le)路(lu)麵(mian)的(de)彎(wan)沉(chen)量(liang),保(bao)證(zheng)了(le)路(lu)麵(mian)不(bu)會(hui)發(fa)生(sheng)過(guo)度(du)變(bian)形(xing)。
(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。
zailiqingmiancengzhongshiyongboxiantugonggezha,qizailiqingmiancengzhongqidaogujiazuoyong,liqingtongzhongjiliaoguanchuanyugezhajian,xingchengfuhelixueqiansuotixi,xianzhijiliaoyundong,zengjialeliqingmiancengzhongdehengxiangyueshuli,liqingmiancengzhonggebufenbiciqianzhi,fangzhileliqingmiancengdetuiyi,congerqidaodikangchezhedezuoyong。
(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)。
boxiantugonggezhazhiyuliqingzhong,shideliqingtongdelashenqiangdudadatigao,zugoudikangzhujiaodadelayinglierbuzhifashenglumianpohuai,jishiyinweijubuquyuchanshengweixiaoliewen,liewenchudeyinglijizhong,jingboxiantugonggezhadechuandierxiaoshi,liewenbuhuifazhanchengliefeng。
(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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