【摘要】：在正常使用環(huán)境下，瀝青混合料無可避免的會出現(xiàn)微小開裂。如果這些病害不能被及時(shí)修復(fù)，微裂紋會進(jìn)一步擴(kuò)展、匯聚，進(jìn)而形成裂縫，影響瀝青路面的正常使用性能和服役壽命。 本文引入生物自修復(fù)的概念，以物質(zhì)補(bǔ)充為手段，利用微膠囊技術(shù)將再生劑包覆并添加在瀝青中。當(dāng)微裂縫擴(kuò)展至微膠囊處時(shí)，微膠囊囊壁破裂，流出的再生劑不但能改善裂紋處瀝青的性質(zhì)、同時(shí)促使裂紋處瀝青能夠在室溫下或較低溫度下自行愈合，從而延緩裂縫的擴(kuò)展甚至完全修復(fù)裂縫，延長瀝青路面的服役壽命。論文主要研究內(nèi)容與結(jié)論如下： 1.分析了現(xiàn)有微膠囊技術(shù)的優(yōu)勢與不足，本文確定了原位聚合法制備瀝青自修復(fù)微膠囊，囊壁材料為脲醛樹脂，囊芯材料為自制瀝青再生劑A。本文詳細(xì)探尋了再生劑微膠囊的制備工藝，得出了制備微膠囊的最佳反應(yīng)條件：①將甲醛與尿素摩爾比為1.5:1的溶液在PH約為8的堿性環(huán)境下，60~75℃反應(yīng)60~75min得到脲甲醛預(yù)聚體；②再生劑乳化階段所用的表面活性劑為十二烷基苯磺酸鈉，濃度為0.5wt%；再生劑乳化階段轉(zhuǎn)速為800r/min；③再將乳化好的再生劑溶液加入預(yù)聚體中，控制攪拌速率為500r/min，囊芯與囊壁質(zhì)量比為1.2:1，稀鹽酸緩慢調(diào)節(jié)溶液至PH=3，同時(shí)緩慢升溫至60℃,2~3h后反應(yīng)結(jié)束；④放慢攪拌速度繼續(xù)攪拌冷卻至室溫，再將含有微膠囊的懸浮液過濾、洗滌、干燥制得微膠囊。對制備出的微膠囊結(jié)構(gòu)性能進(jìn)行分析，結(jié)果表明，微膠囊形貌良好，表面致密，包覆率為84.94%，囊芯含量為82.46%，平均粒徑為21.14um，分布主要集中在5um到35um之間，該部分微膠囊占總體的73.0%。 2.通過自愈合延度試驗(yàn)和自愈合DSR試驗(yàn)研究了再生劑微膠囊對瀝青自修復(fù)能力的影響。自愈合延度試驗(yàn)分析可知：微膠囊摻量為0.3wt%時(shí)，對于瀝青的自修復(fù)能力有明顯提升，且不會大幅降低瀝青性質(zhì)。自愈合DSR試驗(yàn)數(shù)據(jù)表明：微膠囊摻量為0.1wt%的瀝青在初次疲勞試驗(yàn)中加載時(shí)間為1120s，抗疲勞能力最強(qiáng)；摻量為0.5wt%的瀝青在再疲勞試驗(yàn)中加載至破壞的時(shí)間為449s，經(jīng)愈合后的抗疲勞能力最強(qiáng)，說明它的愈合效果較好，自修復(fù)能力最強(qiáng)。得出結(jié)論，少量摻量的微膠囊能夠有效增加瀝青的疲勞壽命，隨著微膠囊摻量的增大，瀝青的整體疲勞壽命減小，，但自修復(fù)能力增強(qiáng)。
[Abstract]:In the normal use environment, asphalt mixture will inevitably appear minor cracking. If these diseases can not be repaired in time, the microcracks will further expand and converge, thus forming cracks, which will affect the normal service performance and service life of asphalt pavement. In this paper, the concept of bioremediation is introduced. By means of material supplement, the regenerative agent is coated and added to asphalt by microencapsulation technology. When the microcrack extends to the microcapsule, the microcapsule wall breaks, and the regenerating agent can not only improve the properties of the crack asphalt, but also promote the crack asphalt to heal itself at room temperature or at lower temperature. In order to delay the expansion of cracks and even completely repair cracks, extend the service life of asphalt pavement. The main contents and conclusions are as follows: 1. The advantages and disadvantages of the existing microencapsulation techniques were analyzed. In this paper, the self-repairing asphalt microcapsules were prepared by in-situ polymerization. The wall materials were urea-formaldehyde resin and the core materials were self-made asphalt regeneration agent A. In this paper, the preparation process of regenerative microcapsules was studied in detail, and the optimum reaction conditions for the preparation of microcapsules were obtained. The optimal reaction conditions: 1: 1 reacted the solution with the molar ratio of formaldehyde to urea 1.5: 1 in the alkaline environment of PH about 8 to obtain the urea-formaldehyde prepolymer at 6075 鈩

本文編號：2179971