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、軟ruan化hua,使shi其qi性xing能neng大da大da降jiang低di,不bu但dan難nan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,而er且qie使shi得de瀝li青qing路lu麵mian更geng加jia凹ao凸tu不bu平ping,而er玻bo纖xian土tu工gong格ge柵zha所suo特te有you的de性xing能neng,完wan全quan滿man足zu瀝li青qing路lu麵mian的de要yao求qiu,目mu前qian許xu多duo工gong程cheng已yi使shi用yong玻bo纖xian土tu工gong格ge柵zha。
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。
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
liqinghunningtuzaigaowenshijuyouliubianxing,zaichelianghezaizuoyongxia,shouliquyuchanshengaoxian,chelianghezaichechuhou,liqingmiancengwufawanquanhuifuyuanzhuangtai,jichanshenglesuxingbianxing,zaicheliangfanfunianyadezuoyongxia,suxingbianxingbuduanjilei,xingchengchezhe。tongguoliqingmiancengjiegoufenxikezhi,gaowenxiadeliqinghunningtuzaishoudaohezaidenianyazuoyong,xingchengleweiliangdeboxingliubian,miancengzhongmeiyourenhekeyiyueshuliqinghunningtuliubiandegujiacailiao,zaochengliqingmiancengliubiandeleijidiejia,zheshixingchengchezhedegenbensuozai。
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
liefengchanshengdefansheyouliangzhong,yizhongshimiancengchanshengliefenghou,liefengxiangxiafanshe,pohuaixiacengjiegou,jiangdilumianjiegouqiangdu,zaiyushuishijie,shuijinruliefengzhong,zaijiaotonghezai(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。 |