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《Road Engineering Materials》

《Road Engineering Materials》. Chapter2 Asphalt materials. ——the method of grading design: trial and error method. Coarse (A) retained in C.R.(%). Medium (B) retained in C.R.(%). Fine (C) retained in C.R.(%). grading Envelope in P. （ % ）. mid-value of Envelope in C.R. （ % ）.

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《Road Engineering Materials》

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  1. 《Road Engineering Materials》 Chapter2 Asphalt materials

  2. ——the method of grading design: trial and error method Coarse (A) retained in C.R.(%) Medium (B) retained in C.R.(%) Fine (C) retained in C.R.(%) grading Envelope in P. （%） mid-value of Envelope in C.R. （%） Mesh size （mm） — — 100 0 16 — 13.2 5.2 — 95~100 2.5 — 9.5 41.7 — — 70~88 18.5 4.75 50.5 1.6 — 48~68 21.0 2.36 2.6 24.0 — 36~53 13.5 Aggregates mixture and design 1.18 22.5 — 24~41 12.0 1.3 0.6 16.0 — 18~30 805 0.3 12.4 — 12~22 7.0 0.15 11.6 — 8~16 5.0 0.075 10.8 13.2 4~8 6.0 pan 1.2 — 86.8 6.0

  3. Sieve size （mm） Passing for each kind aggregate (%） Objective envelope（%） Crushed agg. chip filler envelope midenvlope 26.5 100 100 100 100 100 19. 97 100 100 95~100 97. 5 16 61.5 100 100 75~90 82. 5 13.2 34.5 100 100 62~80 71 9.5 19.8 93.8 100 52~72 62 4.75 4.6 77.9 100 38~58 48 2.36 — 58.7 100 28~46 37 1.18 — 36.0 100 20~34 27 0.6 — 23.0 97 15~27 16 0.3 — 11.0 94 10~20 15 0.15 — — 92 6~14 10 0.075 — — 70.5 4~8 6 Example of Aggregate Mixture Design (65.5) (29)

  4. results 42.3 46.8 10.9 100 41.0 46.8 10.9 98.7 26.0 46.8 10.9 83.7 14.6 46.8 10.9 72.3 8.4 43.9 10.9 63.2 1.9 36.5 10.9 49 — 27.5 10.9 38.4 — 16.8 10.9 27.7 — 10.8 10.6 21.4 — 5.1 10.2 17.3 — — 10.0 10.0 — — 7.7 7.7 Synthesis gradation Sieve size （mm） 不同规格集料各筛上通过量（%） Objective envelope（%） Crushed agg.×42.3 Chip ×46.8 Filler ×10.9 envelope 26.5 100 100 100 100 19. 97 100 100 95~100 16 61.5 100 100 75~90 13.2 34.5 100 100 62~80 9.5 19.8 93.8 100 52~72 4.75 4.6 77.9 100 38~58 2.36 — 58.7 100 28~46 1.18 — 36.0 100 20~34 0.6 — 23.0 97 15~27 0.3 — 11.0 94 10~20 0.15 — — 92 6~14 0.075 — — 70.5 4~8

  5. Main topics Introduction Petroleum Asphalt 2.1 Technical Property of Petroleum Asphalt 2.2 Polymer Modified Asphalt 2.3 Other Asphalt 2.4

  6. Petroleum asphalt 2.1

  7. Petroleum asphalt 2.1 Petroleum Asphalt ——Introduction Organic cementing materials Pitches Asphalts (Bitumen) Tars Natural deposits Petroleum asphalts Lake asphalts See asphalts Rock asphalts Cutback asphalts (liquid) Asphalt cement (solid or semi-solid) Blown asphalt (semi-solid) Emulsified asphalts (liquid) Rapid curing Medium curing Slow curing

  8. ——Asphalt processing Distillates Gasoline, kerosene, Diesel oil, etc Processing Still Air Gasoline Petroleum asphalt 2.1 Asphalt cement Asphalt cement Diesel oil Asphalt cement Water Asphalt cement Emulsifying agent Petroleum refinery Residual matter Rapid-curing Cutback asphalt Air-blown asphalt Asphalt cement Kerosene Medium-curing Cutback asphalt Slow-curing Cutback asphalt Emulsified asphalt

  9. Petroleum asphalt 2.1 正庚烷沉淀 不可溶解部分 可溶解部分 Asphaltene （沥青质） Soft Asphaltene （软沥青质） 正庚烷冲洗 甲苯冲洗 甲苯/乙醇冲洗 ——Components of Petroleum Asphalt（沥青组分） Asphalt Saturated （饱和分） Aromatics （芳香分） Resin （胶质）

  10. Petroleum asphalt 2.1 ——Components of Petroleum Asphalt（沥青组分） 四组分：饱和分（Saturated）芳香分（Aromatics ）胶质（Resin ）沥青质（Asphaltene ） （ S, Ar, R, As ）

  11. Petroleum asphalt 2.1 ——Colloid structure of Petroleum Asphalt（沥青的胶体结构） sol-gel type Gel type 2 4 1 2 4 1 4 sol type 3 3 Diagramof Colloid structure of Petroleum Asphalt 1- Saturated； 2-Aromatics； 3- Resin； 4-Asphaltene

  12. Petroleum asphalt 2.1 ——Colloid structure of Petroleum Asphalt（沥青的胶体结构）

  13. Technical Property of Petroleum Asphalt ——introduction 2.2 密度 体积 膨胀 系数 介电 常数 黏 度 稠 度 延性 脆性 针入 度指 数 （PI） main properties of asphalt physical properties Viscosity （黏滞性） low temperature property temperature susceptibility Adhesiveness 黏附性 Durability 耐久性 visco-elastic 粘弹性

  14. Technical Property of Petroleum Asphalt ——Density 2.2 Relative density (25℃/25 ℃)= Asphalt density (15 ℃) ×0.996 Weigh the following mass successively: 1. m瓶 2. m瓶+满水 3. m瓶+沥青 4. m瓶+沥青+水 密度瓶

  15. Technical Properties of Petroleum Asphalt 2.2

  16. 银烛秋光冷画屏， 轻罗小扇扑流萤。 天阶夜色凉如水，坐看牵牛织女星。 ——杜牧 Across the screen the autumn moon stares coldly from the sky; With silken fan I sit and flick the fireflies sailing by, The night grows colder every hour,—— it chills me to the heart To watch the Spinning Damsel from the herd boy far apart. By Du Mu

  17. Technical Property of Petroleum Asphalt ——Viscosity (黏滞性) 2.2 当 得到表征动力粘度的公式： 动力黏度与密度之比为运动黏度： Viscosity means a capability that the particles of asphalt material resist shearing deformation under external force. 表示沥青层间的速度变化梯度（剪变率）为一个单位 时，单位面积沥青可承受的的内磨阻力。

  18. Technical Property of Petroleum Asphalt ——Viscosity (黏滞性) 2.2 Viscosity can be measured by different methods. Measurement on viscosity 动力黏度 （Pa.S） 运动黏度 （mm2/S） 表观黏度 （Pa.S） 相对黏度 真空减压 毛细管法 毛细管法 布洛克菲尔德 粘度计法 稠 度 高温稳定性 针入度 （0.1mm） 软化点 （℃）

  19. Technical Property of Petroleum Asphalt ——Relative viscosity: Penetration（针入度） 2.2 Schematicof penetration test Penetrometer Relative viscosity such as penetration is consistency rather than viscosity actually, which means a standard needle penetrates depth (0.1mm) into the asphalt sample under specified conditions (test temperature 25℃, mass of standard needle 100g, time of penetration 5s). So penetration can be expressed as P25℃,100g,5s. The lower of penetration value, the higher consistency is. Penetration not only expresses the consistency of asphalt sample, but it is the basis of asphalt grading. The greater of the value of penetration, the higher asphalt grade is.

  20. Technical Property of Petroleum Asphalt ——Relative viscosity:Softening point (软化点) 2.2 Schematic of softening point test Softening point test apparatus • Softening point expresses the specified softening level (℃: TR&B) of asphalt sample when heated under some specified conditions (e.g. rate of temperature: 5℃/min.). • The higher softening point, the better of performance at high temperature asphalt is. • Softening point can be considered as a temperature under same consistency, while penetration is a consistency under same temperature condition.

  21. Technical Property of Petroleum Asphalt ——properties at low temperature: Ductility（延度） 2.2 Test specimen Demonstration of ductility test • Ductility is the total plastic deformation (mm) of asphalt sample when it is stretched under specified condition (e.g. temperature: 15℃ or10 ℃, drawing speed: 5cm/min.). • The greater ductility at lower temperature, the better low temperature performance of asphalt is.

  22. Technical Property of Petroleum Asphalt ——Temperature susceptibility（感温性） 2.2 • Asphaltic material may vary from solid to liquid, depending on the temperature. This characteristic is known as temperature susceptibility. • Temperature susceptibility can be expressed as penetration index (PI: 针入度指数) and index of penetration and viscosity number (PVN：针入度黏度指数). • The former indicates the temperature susceptibility of asphalt under softening point, while the latter indicates the property above the softening pointer.

  23. Technical Property of Petroleum Asphalt ——Temperature susceptibility（感温性） 2.2 • PI can be expressed as: Here: which（A） is coefficient of penetration and temperature. • PI determining (1) When temperature of asphalt is at the softening point, penetration of the asphalt is nearly 800(0.1mm) at this temperature, So

  24. Technical Property of Petroleum Asphalt ——Temperature susceptibility（感温性） 2.2 (2) Measuring several penetrations under different temperature condition (such as 15℃, 20 ℃, 25 ℃, 30 ℃, etc), through the mathematical regression, the coefficient of penetration and temperature (A) is find out. (Note the regression coefficient should not less than 0.997) (3) Through the monograph to find PI directly.

  25. Technical Property of Petroleum Asphalt ——Temperature susceptibility（感温性） 2.2 Significance of PI • Expressing the degree of temperature susceptibility under softening point; • The greater PI, the lower temperature susceptibility of asphalt is; • Division types of colloid structure of asphalt: PI<-2, sol type PI>+2, gel type PI= -2~ +2, sol-gel type

  26. Technical Property of Petroleum Asphalt ——Temperature susceptibility（感温性） 2.2 • Equivalent softening point: means the corresponding temperature when penetration is 800(0.1mm), which shows the high temperature performance of asphalt. • Equivalent breaking point: the corresponding temperature when penetration is 1.2(0.1mm), which reflects the low temp. performance.

  27. Technical Property of Petroleum Asphalt ——Adhesiveness (黏附性) 2.2 • When asphalt mixes with aggregate particles, asphalt forms film on the particles. Adhesiveness represents connection degree of this thin film. The higher degree, the better adhesiveness is. • Alkali aggregate has better adhesiveness with asphalt than acid agg, which means the better water stability of asphalt mixture is. • Evaluation method: Boiling water method for coarse agg; Immersion method for fine agg.

  28. Technical Properties of Petroleum Asphalt 2.2

  29. Technical Property of Petroleum Asphalt ——Durability (耐久性) 2.2 旋转薄膜烘箱 (Rotate thin film oven test) 压力老化箱 (Pressure aging vessel) 薄膜烘箱 (Thin film oven test) • Influence factors on durability of asphalt: temperature oxidation ultraviolet ray water hardening • Evaluation methods thin film oven test（TFOT）: for short-term aging rotation thin film oven test (RTFOT): for short-term aging, especially for modified asphalt pressure aging vessel (PAV): for long-term aging • Evaluation indexes mass loss penetration ratio residual ductility

  30. Technical Property of Petroleum Asphalt ——Visco-elastic property (黏弹性) 2.2 • Asphalt is a typical visco-elastic material, which means asphalt shows viscosity property under low temperature condition while shows elastic property under high temperature condition. • This kind special property can be expressed by the stiffness modulus. This modulus is related not only with stress and strain, but with temperature and loading time. • Stiffness of asphalt can be read from the nomograph.

  31. Technical Property of Petroleum Asphalt ——Visco-elastic property (黏弹性) 2.2 Nomograph of asphalt stiffness modulus

  32. Technical Specifications of Petroleum Asphalt 2.2 • Based on current specifications of our country, asphalt marks are divided by penetration, which means the greater penetration, the higher marks asphalt is. • To heavy traffic asphalt (GB/T15180—2000), the are 5 marks: AH-50, AH-70, AH-90, AH-110 and AH-130. • To road petroleum asphalt (JTG F40-2004), there are 7 marks, commonly used asphalt marks are: mark50, mark70, mark90, mark110 and mark130, etc.

  33. Technical Specifications of Petroleum Asphalt 2.2 The smaller of penetration, the lower mark asphalt is, and the more consistency to asphalt, which this mark of asphalt is more suitable to the hot weather condition.

  34. Technical Specifications of Petroleum Asphalt 2.2 Chinese specification 粘稠道路石油沥青（针入度分级penetration grade）

  35. Technical Specifications of Petroleum Asphalt 2.2 Grades Suitable for A All layers of all grade highway B Lower layer of expressway and first grade highway All layers of second and under second grade highway Used for basis asphalt C All layers of third and under third grade highway Asphalt quality grades (沥青质量等级)

  36. Technical Specifications of Petroleum Asphalt 2.2 ——The briefIntroduction of Stratagem Highway Researching Plan (SHRP) in America • 美国战略公路研究计划(SHRP)是1987年由美国国会通过的一项为期5年（1988-1992）的研究计划，其投资总额为1.5亿美元，目的是改善其国家道路的使用性能和耐久性，使得这些道路对使用者及其维护者都更加安全。该计划的资金来自联邦资助公路基金的0.25％的预留费。开发及评价道路施工、养护、管理创新技术的工作都以合同的形式委托给了大学、咨询机构和研究人员。研究成果分为四大部分：沥青、混凝土及结构、路面性能、公路管理等。 • 1991年ISTEA(水路运输功效联合法案)提供了1.08亿美元，由联邦公路管理局(FHWA)管理，主要是用6年的时间帮助各州及公路行业把SHRP的成果推广应用并继续路面长期性能(LTPP)的研究。 • 如今，已开发的SHRP技术每年可以为美国节约大量的资金。联邦公路管理局已开发出一个有效的、创新的、灵活的实施计划，并承诺和公路行业的合作伙伴一起尽快地、有效地发挥这些效益. 

  37. Technical Specifications of Petroleum Asphalt 2.2 ——characteristicsof SHRP • Asphalt properties are evaluated according to different three stages: ——during the transportation and storage stage; ——blending and spreading process; ——service stage of asphalt pavement. • All specifications are provided under same requirement rather than same temperature. • Put forward some new evaluate indexes and corresponding instruments.

  38. ——The briefIntroduction of SHRP Technical Specifications of Petroleum Asphalt 2.2 RV试验（P48） Rotary viscosimeter（旋转式粘度计）：measure viscosity of asphalt (用于测量沥青的 粘度).

  39. Technical Specifications of Petroleum Asphalt 2.2 ——The briefIntroduction of SHRP DSR试验 Dynamic Shear Rheometer（动态剪切流变仪）（P58）：Determination of viscoelastic properties of asphalt within temperature at 5-85℃ before and after aging, and also presentation the ability for anti-rutting at high temperature condition (测定未老化和老化之后的沥青在5-85℃温度范围内线粘弹性性质，并可用于反映沥青的高温抗车辙能力).

  40. ——The briefIntroduction of SHRP Technical Specifications of Petroleum Asphalt 2.2 DTT试验（P51） Direct Tension Test（直接拉伸仪）：Evaluation of asphalt material performances at low temperature, such as stress and strain when destruction, especially to evaluate the performances for polymer modified asphalt. (评价低温下沥青胶结料性质，如破坏时的应力和应变，特别适用于聚合物改性沥青，也用于评价沥青的低温性能)

  41. ——The briefIntroduction of SHRP Technical Specifications of Petroleum Asphalt 2.2 BBR试验（P50） Bending Beam Rheometer （弯曲梁流变仪）：Measurement accurately of stiffness at low temperature and creep rate for asphalt (精 确测量沥青的低温劲度模量和蠕变速率,用于评价沥青的低温性能).

  42. Technical Specifications of SHRP 2.2

  43. Other Asphalt 2.3

  44. http://wenku.baidu.com/view/738de20c844769eae009ed5a.html 这张图是从网络上得到的截图（网址如上），表达了young式方程。注意由于考虑的三相体与书中的不同，所以这里： 说明书中的式2-26符号也有误。所以将上式带入式2-25正确表达式， ，得到与书中相同的结果：

  45. Polymer Modified Asphalt 2.3.1

  46. Polymer Modified Asphalt ——Introduction 2.3.1 Purposes of modification Improve high temperature stability Resist cracking under low temperature Enhance anti-aging capability Improve adhesiveness between asphalt and aggregate

  47. Polymer Modified Asphalt ——classifications 2.3.1 Anti-rutting agent Rubber SBS fiber • Main types of modifications: • Resin—聚乙烯（PE）、乙烯-乙酸共聚物（EVA）; • Rubber—丁苯橡胶（SBR）、废弃轮胎橡胶粉; • Thermoplastic elastomeric—苯乙烯丁二烯嵌段聚合物（SBS）.

  48. Polymer Modified Asphalt ——IndexEvaluation Methods 2.3.1 • Segregation test（离析试验）——to judge the consolute stability between modified agent and asphalt; • Elastic recovery test（弹性恢复试验）——to evaluate automatic recovery capacity on deformation for asphalt modified with SBS after stretching; • Dynamometric ductility test(测力延度试验)——to detect the ability of modified asphalt resisting external tension. • Toughness and tenacity test（黏韧性试验）——to be appropriate for asphalt modified with rubber,

  49. Polymer Modified Asphalt ——Commonly Used modified asphalts 2.3.1 • Type of thermoplastic elastomer (热塑性橡胶类)—— SBS(苯乙烯丁二烯嵌段聚合物)； • Type of rubber（橡胶类）—— SBR(丁苯橡胶)； • Type of thermoplastic resin（热塑性树脂类）—— PE(聚乙烯)，EVA(乙烯-乙酸乙烯共聚物)； • Type of thermosetting resin（热固性树脂类）——EP(环氧树脂).

  50. Polymer Modified Asphalt ——SBS modified asphalt 2.3.1 SBS原料 • SBS modified asphalt is most widely used on road pavement at present. Because this type modified asphalt can be benefit both to high and low temperature performances. • SBS is a polymer made ofbutadiene (丁二烯) and styrene (苯乙烯) in embedded way. • It is this special structure that makes SBS particular features.

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