目前，陜西瀝青路面鋪筑使用的找平基準主要有4種型式：一(yi)是(shi)固定基(ji)準，即懸線法(fa)；二是(shi)接觸跨越式浮動平衡(heng)梁基(ji)準；三是(shi)非接觸式電子平衡(heng)梁基(ji)準；四是(shi)滑(hua)靴(xue)式基(ji)準。實踐證明，在下面層(ceng)、中(zhong)面層(ceng)采(cai)用(yong)懸線法，中(zhong)面層(ceng)、上面層(ceng)采(cai)用(yong)接觸(chu)跨越式浮動平(ping)衡(heng)梁基準(zhun)或非(fei)接觸(chu)式電子平(ping)衡(heng)梁基準(zhun)鋪筑(zhu)的效果良好。4種方式可作以下比較。

(1)使用(yong)固(gu)定基(ji)準(zhun)(zhun)(zhun)（懸線(xian)法）能在較(jiao)大范圍內(nei)準(zhun)(zhun)(zhun)確地(di)控制設(she)計標高(gao)(gao)(gao)、縱橫坡度(du)、路(lu)面厚度(du)和(he)平(ping)整度(du)。操作方法是：選用(yong)直徑2 mm的(de)高(gao)(gao)(gao)強鋼(gang)絲(si)，長度(du)200 m，張緊(jin)度(du)為800~1 000 N，基(ji)準(zhun)(zhun)(zhun)線(xian)應(ying)盡量靠(kao)進熨平(ping)板，以(yi)減少(shao)厚度(du)增量值。基(ji)準(zhun)(zhun)(zhun)線(xian)兩(liang)根立(li)桿(gan)的(de)間(jian)(jian)距一般(ban)為5~10 m，用(yong)兩(liang)臺精密水準(zhun)(zhun)(zhun)儀監(jian)測立(li)桿(gan)的(de)高(gao)(gao)(gao)程(cheng)(cheng)，每(mei)兩(liang)根立(li)桿(gan)之(zhi)間(jian)(jian)鋼(gang)絲(si)繩的(de)撓度(du)不(bu)大于2 mm，彎道(dao)處應(ying)加密。立(li)桿(gan)要(yao)高(gao)(gao)(gao)于鋪層75~150 mm，埋設(she)牢(lao)固(gu)，距鋪層邊緣160~500 mm。鋼(gang)絲(si)架設(she)高(gao)(gao)(gao)程(cheng)(cheng)應(ying)高(gao)(gao)(gao)于虛鋪高(gao)(gao)(gao)程(cheng)(cheng)50~100 mm，用(yong)細(xi)鐵絲(si)綁緊(jin)在立(li)桿(gan)支撐架凹槽上(shang)。作業期間(jian)(jian)應(ying)有(you)專人看管(guan)，嚴禁碰撞鋼(gang)絲(si)。

(2)使(shi)用(yong)接(jie)觸(chu)跨(kua)(kua)越(yue)式浮(fu)動(dong)(dong)平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)時(shi)(shi)，為(wei)保證(zheng)面層整(zheng)體平(ping)(ping)(ping)(ping)(ping)(ping)整(zheng)度(du)(du)(du)(du)(du)，中面層、上(shang)面層用(yong)平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)。為(wei)提(ti)高平(ping)(ping)(ping)(ping)(ping)(ping)整(zheng)度(du)(du)(du)(du)(du)，應(ying)(ying)盡量加長(chang)平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)的(de)(de)(de)(de)長(chang)度(du)(du)(du)(du)(du)，注意滑(hua)靴和平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)行(xing)走輪不要(yao)黏上(shang)瀝青，以防影響攤(tan)鋪(pu)(pu)(pu)(pu)層的(de)(de)(de)(de)平(ping)(ping)(ping)(ping)(ping)(ping)整(zheng)度(du)(du)(du)(du)(du)。浮(fu)動(dong)(dong)平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)有很好的(de)(de)(de)(de)濾波作用(yong)，避免了固(gu)定基準折線和人為(wei)誤差的(de)(de)(de)(de)影響，大大提(ti)高了路(lu)(lu)面平(ping)(ping)(ping)(ping)(ping)(ping)整(zheng)度(du)(du)(du)(du)(du)。跨(kua)(kua)度(du)(du)(du)(du)(du)16~17.6 m的(de)(de)(de)(de)平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)要(yao)求(qiu)是直線攤(tan)鋪(pu)(pu)(pu)(pu)，攤(tan)鋪(pu)(pu)(pu)(pu)彎(wan)道時(shi)(shi)要(yao)求(qiu)彎(wan)道的(de)(de)(de)(de)半(ban)徑(jing)大于600 m，否則由于彎(wan)道的(de)(de)(de)(de)變化引起平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)滾(gun)輪和滑(hua)靴產生較(jiao)大的(de)(de)(de)(de)扭(niu)矩而發(fa)生橫(heng)(heng)向(xiang)位移(yi)，不但(dan)起不到平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)作用(yong)，反(fan)而破壞整(zheng)個(ge)平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)系(xi)(xi)統，攤(tan)鋪(pu)(pu)(pu)(pu)出(chu)的(de)(de)(de)(de)路(lu)(lu)面厚薄(bo)不均勻(yun)，影響路(lu)(lu)面的(de)(de)(de)(de)平(ping)(ping)(ping)(ping)(ping)(ping)整(zheng)度(du)(du)(du)(du)(du)。因此在(zai)(zai)攤(tan)鋪(pu)(pu)(pu)(pu)半(ban)徑(jing)小于600 m的(de)(de)(de)(de)彎(wan)道時(shi)(shi)，除(chu)攤(tan)鋪(pu)(pu)(pu)(pu)機轉(zhuan)向(xiang)應(ying)(ying)緩(huan)慢(man)過渡外(wai)，還應(ying)(ying)拆(chai)掉部(bu)分平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)，使(shi)其(qi)平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)變短，減小平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)橫(heng)(heng)向(xiang)位移(yi)，提(ti)高路(lu)(lu)面的(de)(de)(de)(de)平(ping)(ping)(ping)(ping)(ping)(ping)整(zheng)度(du)(du)(du)(du)(du)。在(zai)(zai)用(yong)浮(fu)動(dong)(dong)平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)鋪(pu)(pu)(pu)(pu)橫(heng)(heng)縫時(shi)(shi)，由于此時(shi)(shi)平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)的(de)(de)(de)(de)后半(ban)部(bu)分是在(zai)(zai)已經攤(tan)鋪(pu)(pu)(pu)(pu)壓實(shi)好的(de)(de)(de)(de)路(lu)(lu)面上(shang)，在(zai)(zai)攤(tan)鋪(pu)(pu)(pu)(pu)前應(ying)(ying)在(zai)(zai)平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)滾(gun)輪下墊1塊長(chang)6 m、寬20 cm、厚度(du)(du)(du)(du)(du)與虛鋪(pu)(pu)(pu)(pu)系(xi)(xi)數相等的(de)(de)(de)(de)木(mu)板，攤(tan)鋪(pu)(pu)(pu)(pu)機起步時(shi)(shi)打(da)開(kai)平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)自(zi)動(dong)(dong)找平(ping)(ping)(ping)(ping)(ping)(ping)系(xi)(xi)統開(kai)關。因為(wei)正常使(shi)用(yong)平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)時(shi)(shi)其(qi)后半(ban)部(bu)是在(zai)(zai)未壓實(shi)的(de)(de)(de)(de)虛鋪(pu)(pu)(pu)(pu)路(lu)(lu)面滾(gun)動(dong)(dong)，如(ru)果此時(shi)(shi)不墊木(mu)板，使(shi)用(yong)平(ping)(ping)(ping)(ping)(ping)(ping)衡(heng)(heng)梁(liang)(liang)(liang)(liang)自(zi)動(dong)(dong)找平(ping)(ping)(ping)(ping)(ping)(ping)系(xi)(xi)統會使(shi)鋪(pu)(pu)(pu)(pu)出(chu)的(de)(de)(de)(de)路(lu)(lu)面厚度(du)(du)(du)(du)(du)減小。

(3)非接觸式(shi)電子平衡梁目(mu)前有(you)激(ji)光式(shi)和超聲波(bo)式(shi)。超聲波(bo)式(shi)平衡梁的超聲波(bo)探(tan)(tan)頭間(jian)距應不(bu)小于60 cm，探(tan)(tan)頭下緣距地面以80~100 cm為(wei)宜，超聲波(bo)探(tan)(tan)頭探(tan)(tan)測區域的半(ban)(ban)徑為(wei)30 cm，所(suo)以在探(tan)(tan)頭的正下方(fang)半(ban)(ban)徑30 cm范(fan)圍內應無(wu)雜物。所(suo)配備的可(ke)調控制(zhi)板(ban)，可(ke)根據實際情(qing)況調節靈敏度、增減鋪(pu)層厚(hou)度和液壓缸升降反應速度。攤鋪(pu)橫(heng)接縫時可(ke)在后面探(tan)(tan)頭下方(fang)設置厚(hou)度等于松(song)鋪(pu)系(xi)數的木板(ban)，以達到(dao)接縫良好的目(mu)的。