Two types of asphalt are available in liquid form:
cutback asphalt emulsified asphalt
Cutback asphalt---- is asphalt cement that is liquefied by blending with petroleum solvents (called diluents).
ability to adhere to solid particles impermeability or water resistance
Uses of bituminous materials
roadways pavements many construction products
such as roofing felt, caulking compound, waterproofing compounds, wallboard, building paper, paints, etc.
5.1.2 Asphalts
Asphalts are cementitious materials in which the predominant constituent materials are bitumens.
Natural deposits or petroleum asphalt The consistency of asphalts varies widely
地沥青
焦油
焦油沥青
天然沥青
石油沥青
天然沥青
岩石沥青
沥青膏 慢凝
稀释(石油)沥青 中凝
乳化沥青
氧化沥青 快凝
Uses of bituminous materials
Bitumens possess a number of properties that make them useful in the construction
when used in pavement construction it is necessary to heat both the asphalt cement and the aggregates prior to mixing．
superior waterproof qualities
Pavement built using paving asphalt is waterproof and resistant to many types of chemical attack.
such as foundations，retaining walls，dams，and bridges．
Aboveground structures experience great fluctuations in environmental conditions，and waterproofing compounds should be able to withstand these changes without becoming brittle or too soft．
Asphalt cement is very sticky and highly viscous, especially prepared with the quality and consistency required in the manufacture of asphalt pavements (hotmix pavements).
When these materials undergo destructive distillation , the resulting condensate冷凝物 is tar．Further processing yields a solid or semisolid residue known as pitch．
waterproof coatings for walls and below-grade structures．
5.1.1 Tars and pitches
Tars, along with pitches, are the products of distillation of materials such as wood, coal, and shale.
Native asphalts or lake asphalts
Lake Trinidad特立尼达岛，West Indies (a 110-acre lake containing about 40 percent bitumen mixed with water, fine siliceous silt, clay, and organic matter);
5.2 Petroleum asphalt
Petroleum asphalts are classified into four types：
Asphalt cements Cutback asphalts Emulsified asphalts Air-blown asphalts
5.2.1 Asphalt Cement
Tar 焦油
Generally by-product of coke (from coal) production
When coal is heated in coke ovens, it is reduced to coke. The gases (vaporized oils) generated during the process are collected from the oven and refined. The distillation of lighter oils produces tar.
处理后得到的产品。
焦油沥青是煤、木材等有机物干馏加工所得的焦油 经再加工后的产品。
工程中采用的沥青绝大多数是石油沥青，石油 沥青是复杂的碳氢化合物与其非金属衍生物组 成的混合物。通常沥青闪点在240℃~330℃之 间，燃点比闪点约高3℃~6℃度，因此施工温 度应控制在闪点以下。
沥青（烃, 碳氢化合物）
from solid to semisolid at normal temperature
The natural deposits of asphalts are of two types：
Natural rock asphalts
Deposits of sandstone or limestone filled with asphalts
Features of bitumen
Completely soluble in carbon disulfide (CS2) Nonvolatile Nontoxic沥青分类
沥青材料分为地沥青和焦油沥青两大类。
地沥青又分为天然沥青和石油沥青
天然沥青是石油渗出地表经长期暴露和蒸发后的残留物； 石油沥青是将精制加工石油所残余的渣油，经适当的工艺
Road Engineering Materials 道路工程材料
College of Automobile and Traffic Engineering 汽车与交通学院
Ch5 Bituminous Materials
5.1 Types of asphalt 5.2 Petroleum asphalt 5.3 Properties of asphalt 5.4 Asphalt grades 5.5 Spray applications 5.6 Testing
Petroleum asphalts are used in
construction of flexible pavements roof construction (asphalt shingles, rolled roofing, and
built-up roofing), for insulation (electrical insulation and building paper) waterproofing (sprays, paints, and bituminous fabrics) canal lining seal subgrades against the migration of water Joint seals
焦油是煤炭在焦化过程中产生的。其产量约占装炉煤的 3%~4%，在常温常压下其产品呈黑色粘稠液状，密度通 常在0.95-1.10g/cm3之间，焦油又称煤焦油。
Tar pitches 焦油沥青
Tar pitches are used for built-up roofing and waterproofing of underground and aboveground construction
5.1 Types of asphalt
Bitumen is a solid，semisolid，or viscous cementitious material，natural or manufactured，and composed principally of various mixtures of complex hydrocarbons ( 烃, 碳氢化合物).
5.2 Petroleum asphalt
Petroleum asphalts are classified into four types：
Asphalt cements Cutback asphalts Emulsified asphalts Air-blown asphalts
5.2.2 Cutback Asphalts
Bermudez，Venezuela (lake asphalt containing about 65 percent bitumen)
Trinidad Lake Asphalt
特立尼达岛 特立尼达和多巴哥的主岛。与委内瑞拉东北部海岸相望，最近