【摘要】：以基質(zhì)瀝青與膠粉攪拌制備橡膠瀝青,以基質(zhì)瀝青與SBS改性劑攪拌制備SBS改性瀝青,然后分別采用相應(yīng)的級(jí)配設(shè)計(jì)橡膠瀝青應(yīng)力吸收層混合料和SBS改性瀝青應(yīng)力吸收層混合料.選取目前常見(jiàn)的Strata應(yīng)力吸收層混合料為對(duì)比材料,通過(guò)大量四點(diǎn)彎曲小梁疲勞試驗(yàn)(15℃)對(duì)這3種改性瀝青混合料進(jìn)行1 500×10~(-6)應(yīng)變下的疲勞試驗(yàn),分析混合料疲勞壽命與膠粉摻量(質(zhì)量分?jǐn)?shù))、SBS改性劑摻量(質(zhì)量分?jǐn)?shù))及改性瀝青針入度、軟化點(diǎn)、黏度的關(guān)系.結(jié)果表明:Strata應(yīng)力吸收層混合料在1 500×10~(-6)應(yīng)變下的疲勞壽命為302 023次,因此以1 500×10~(-6)應(yīng)變下疲勞壽命≥3×10~6次作為應(yīng)力吸收層混合料的設(shè)計(jì)指標(biāo).橡膠瀝青應(yīng)力吸收層混合料疲勞壽命與膠粉摻量和橡膠瀝青177℃黏度具有很好的相關(guān)性,按設(shè)計(jì)指標(biāo)進(jìn)行橡膠瀝青應(yīng)力吸收層混合料設(shè)計(jì)時(shí),要求膠粉摻量為19.6%~20.5%,橡膠瀝青1 77℃黏度維持在3.4~3.6 Pa·s.SBS改性瀝青應(yīng)力吸收層混合料疲勞壽命與SBS改性劑摻量和SBS改性瀝青針入度、軟化點(diǎn)、1 35℃黏度具有很好的線性相關(guān)性,按設(shè)計(jì)指標(biāo)進(jìn)行SBS改性瀝青應(yīng)力吸收層混合料設(shè)計(jì)時(shí),若A型、B型SBS改性劑混合使用,則要求SBS改性劑摻量≥6.5%,SBS改性瀝青針入度≤5.1 mm,SBS改性瀝青軟化點(diǎn)≥93℃,SBS改性瀝青135℃黏度≥1.95 Pa·s;適當(dāng)加大油石比和調(diào)整級(jí)配中關(guān)鍵篩孔通過(guò)率可增大SBS改性瀝青應(yīng)力吸收層混合料疲勞壽命;B型SBS改性劑更適合用在SBS改性瀝青應(yīng)力吸收層混合料設(shè)計(jì)中.
[Abstract]:Rubber asphalt was prepared by mixing matrix asphalt with rubber powder, SBS modified asphalt was prepared by mixing matrix asphalt with SBS modifier, and rubber asphalt stress absorption layer mixture and SBS modified asphalt stress absorption layer mixture were designed by corresponding gradation. In this paper, the common Strata stress absorbing layer mixture is selected as the contrast material, and the fatigue test of these three modified asphalt mixtures under 1 500 脳 10 ~ (-6) strain is carried out through a large number of four-point bending trabecular fatigue tests (15 鈩，

本文編號(hào)：2350997