11/22/2017
Composition
Estimating Training Manual
• Concrete is a composite material • Composition: ▫ Portland Cement ▫ Aggregate ▫ Water ▫ Chemical admixtures Super plasticizers Accelerators Retarders
Dhruti Patel Estimating Department
ASTM Portland Cement Types
Estimating Hierarchy
Description
Type Purpose
Pre cast concrete Prestressed concrete Concrete not in direct contact with soil or ground water Pre cast concrete Pre stressed Concrete exposed to soil and ground water
Strategies
General Purpose
I
Scheduling
Moderate Sulfate Resistance II
Emergency construction and repairs Fast turnover of molds Construction of machine bases and gate installations Put up walls in one pour
Type of Building
Rapid Hardening
III
Low Heat
IV
Not commonly used and special order only
Owner’s Goal
Sulfate Resistance
V
Not commonly used and special order only
Chemicals in Concrete
Chemical
Result
Purpose
Air bubbles within
Decreasesfree thaw effect observed in temperature fluctuating regions Easierto pump up and transport if constructing super structure
Air Entraining
Concrete
concrete mixture
Super Plasticizer
Liquid concrete
1
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