08: Bituminous Concrete Flashcards
These are strong cements, durable, highly waterproof, and readily adhesive
Bituminous Concrete
These are also highly resistant to the action of most acids, alkalis, and salts.
Bituminous Concrete
This type of material is widely used in construction projects from building to highway and heavy construction.
Bituminous Concrete
An Example of Natural Asphalt
The Pitch Lake of Trinidad Island in LA, California
Rock asphalt are asphalt ___ in ____ rocks
Impregnated, Porous
A dark brown to black cementious material, solid or semi-solid in consistency in which the predominating constituents are bitumen which occur in nature as such or are obtained as residue in refining petroleum.
Soluble in most petroleum product
Asphalt
A brown or black bituminous material, liquid or semi-solid in conssitency, in which the predominating constituents are bitumen obtained as condensates in the destructive distillation of coal, petroleum, wood, or other organic materials.
Resistant to petroleum-based solvents
Lower in content of bitumen compared to asphalt
Tar
To eliminate the need to heat the asphalt to a liquid before it can be used in construction, the cement can be modified into a ____ and _____
Term: Liquid Asphalt
For Blank: Cutback Asphalt, Emulsified Asphalt
The ___ are produced by cutting the asphalt cement with petroleum solvent.
Cutback Liquid Asphalt (or Asphalt Cutbacks)
Classification of Asphalt Cutbacks in terms of relative speed of evaporation of the solvent
Rapid Curing (RC)
Medium Curing (MC)
Slow Curing (SC)
Asphalt cement in a volatile solvent in the gasoline or naphtha boiling range.
Rapid Curing (RC)
Asphalt cement and a solvent in the kerosene boiling range.
Medium Curing (MC)
Asphalt cement and an oily solvent which has low volatility.
Slow Curing (SC)
___ are produced by separating the hot asphalt cement into minute globules and dispering them in water that has been treated with emulsifying agent.
Emulsified Asphalt (or Asphalt Emulsions)
In asphalt emulsion, this works best with positive charged aggregates such as limestone and dolomite.
Anionic (negative charge)
In asphalt emulsion, this works best with siliceous and wet aggregates.
Cationic (positive charge)
Classification of Asphalt Emulsions
Grade - Anionic - Cationic
Rapid Setting - RS - CRS
Medium Setting - MS - CMS
Slow Setting - SS - CSS
General term referring to any pavement that has surface constructed with asphalt.
Asphalt Pavements
Normally, it consists of a surface (layer) of mineral aggregate coated and cemented with asphalt and one or more supporting courses which may be following types:
Asphalt Pavements Types:
Asphalt Base (Asphalt-Aggregate Mixture)
Crushed Stone (Rock), Slag, or Gravel
Portland Cement Concrete
Old Brick or Stone Block Pavements
In Asphalt Pavements, the upper or top layer is ___
Asphalt Wearing Surface
It may range from less than 1 inch to several inches in thickness, depending on a variety of design factors.
Asphalt Pavements (Asphalt Wearing Surface Layer)
Generally, it is preferred to treat the granular material used in bases. The most common treatment is to mix asphalt, thus producing an asphalt base. A ___ thickness of asphalt base is about equal to a ____ thickness of untreated granular base when it comes to load-carrying performance.
1-inch, 2-inch to 3-inch
When the entire pavement above the subgrade consists of asphalt mixtures, it is called ____. This is generally considered the most modern and dependable type of pavement for present-day traffic.
A Full-Depth Asphalt Pavements
Asphalt Pavement Construction
Preparation of Asphalt Concrete:
Plant Mix
Mixed-In-Place (Road Mix)
Recycled Asphalt Concrete
Slurry Seal
Asphalt paving mixtures prepared in a central mixing plant. Mostly done for high strength design requirement.
Plant Mix
Mixture is done on site by rotary mixer or traveling mixing plant under moderate to warm weather temperatures. Emulsified asphalt and cutback asphalts are used in this method of preparation.
Mixed-In-Place (Road Mix)
Combined reclaimed pavement materials and new materials to produce asphalt mixture that meet normal specification. requirements. Old pavements are crush into desired sizes and added as part of the concrete mix.
Recycled Asphalt Concrete
Thin asphalt overlay applied by a continuous process machine. to worn pavements to seal them and provide a new wearing surface using emulsified asphalt. Uniformly graded aggregate from a particle size about the thickness of the finished overlay down to No. 200.
Slurry Seal
Asphalt Spray Applications
Surface Treatments and Seal Coats
Tack Coats and Prime Coats
Penetration Macadam
The Roller Operation
A sprayed-on application of asphalt to a surface, with or without a thin layer of covering aggregates, is called an asphalt ____. Sometimes these sprayed-on applications are included in the original construction. The addition of covering aggregates over the spraved-on asphalt restores and improves the skid resistance of the wearing surface. Surface treatments have waterproofing or texture improvement, or both, as their main purpose are called as ____
Surface Treatments, Seal Coats
____ is a sprayed thin coating of asphalt to bind the existing and the new pavement. While ____ is sprayed on granular base so that it will seep into or penetrate the base and serves as a binder for the pavement to be constructed.
Tack Coats, Prime Coats
Asphalt ____ pavement consists of one or more layers of large-sized broken stone and rock chips interlocked by rolling. Fluid asphalt is sprayed onto each layer, and it seeps into or penetrates the layer to bind the stones together.
Penetration Macadam
Rolling should start as soon as possible after the material has been spread. Rolling consists of three consecutive phases:
The Roller Operation
- Breakdown/Initial Rolling – compacts the material beyond that imparted by the paver to obtain all of the density it needs.
- Intermediate Rolling – densifies and seals the surface.
- Finish Rolling – removes roller marks and other blemishes left from previous rolling.
Deficiencies on Asphalt Mix
- Too hot
- Too cold
- Too much asphalt
- Too little asphalt
- Non-uniform mix
- Excess coarse aggregate
- Excess fine aggregate
- Excess moisture
- Miscellaneous
