concrete repair materials and selection criteria
TRANSCRIPT
Ali H. Al-Gadhib
by
Civil Engineering DepartmentKFUPM
Presentation Flow
• Concept of Load / Capacity Envelope
• Dimensional Incompatibility Behavior
• The Specialist Formulator
• Total Package Solution
• Concrete Repair Systems
• Criteria for Selection of Repair Materials
• Conclusions
The Specialist Formulator
Is one who employs materials scientists and chemists to take basic materials from the petrochemicals, plastics, cement, aggregate, and other related industries and tailor them into useful repair materials which can be applied in as simple a manner as possible on site.
INVESTMENT ON R&D
Company I
4% of the total annual turnover
=
Company II
4% of the total annual turnover
=
Result of 46 Repair Material
Ten
sile
Str
ess
Time
Tensile stress relief throughtensile creep
Elements of a cementitious ‘repair package’
Typical PropertiesTypical PropertiesFor Acrylic Reinforced Cementitious, Flexible
Waterproof Coating
(1) The shrinkage compensation agent is included to
counteract the natural phenomenon of contraction
due to low of moisture. These agent have two
distinct mechanism to wok at plastic.
(2) Silica fume is to impart dense matrix and enhance
water tightness or wall is increase strength.
(3) Polymer is added in powder form to increase
flexibility, adhesion, and water tightness.
(4) Microfibers to impart flowability and badge cracks.
(5) Pulverized superplasticers to increase workability
after a low which ratio.
Polymer Modified CementatiousRepair Mortar
• Modified cementations• Polymer modified cementations• Polymer fiber modified cementations• Epoxy – base resin• Epoxy – cementations repair• Crack injection• Micro concrete• Corrosion inhibitors• Protective systems• External strengthening
Reinforced Concrete Repairand it Protection Systems
Compressive strength (N/mm2) 55-110
Compressive modulus (kN/mm2) Flexural strength (N/mm2) 25-30
Elongation at break (%) 8-17
Linear coefficient of thermal expansion per oCWater absorption, 7 days at 25o C (5)Maximum service temperature under load (o C)
Rate of development of strength at 20o C
Polyester resin groutsmortars and concretes,
25-35 10 6
50-80
2-6 hours
Polymer modifiedcementitious systems
10-80
6-152-8
8-20 10 6
100-300
1-7 days
Physical Properties ofRepair Materials
Companies of Concrete Repair
1) Degussa Company www.degussa.com
2) Sika Company
www.sika.com
3) Fosroc Company
www.fosroc.com
Indices for Durable Repair
• Repair Diffusivity• Free Drying Shrinkage• Free Specific Tensile Creep• Repair Tensile Strength• Tensile Modulus of Elasticity
No matter how superior the
repair material system,
it can not go beyond and bypass
the quality of workmanship