Structural Video

An Introduction to Special Concretes

Course Description:
For purposes of this course, special concretes are considered to be those which contain materials that are not routinely used in conventional structural or mass concrete, those which are not proportioned using conventional procedures, or those which are placed with equipment or by methods which require additional attention be given by the Owner to assure the required quality is achieved. 

Course Outline:
1. GENERAL
2. PREPLACED-AGGREGATE CONCRETE
3. UNDERWATER CONCRETE
4. BLOCKOUT CONCRETE
5. HIGH-STRENGTH CONCRETE
6. PUMPED CONCRETE
7. FIBER-REINFORCED CONCRETE
8. POROUS CONCRETE
9. FLOWING CONCRETE
10. SILICA-FUME CONCRETE

Learning Objectives:
At the conclusion of this course, the student will be able to:

• Delineate preplaced-aggregate concrete produced by placing coarse aggregate in a form and later injecting a portland-cement-sand fly ash grout, usually with chemical admixtures, to fill the voids.
• Determine underwater concrete placements for locations and sizes of the area to be concreted that are well defined, and how they must be thoroughly cleaned and free of mud, silt, and debris.
• Explain about the use of blockouts in concrete members necessary to embed seats, guides, rails, piping, and electrical and mechanical systems into concrete placements.
• Describe high-strength concrete used to reduce column dimensions and to meet special project objectives such as in large composite columns, stiffer structures, bridges, stilling basins, and structures subject to chemical attack.
• Explain about pumped concrete used for most structural concrete construction but which is most useful where space for construction equipment is limited or access is difficult.
• Delineate about fiber-reinforced concrete (FRC) which contains dispersed, randomly oriented fibers and can be used for pavements, overlays, patching, floor slabs, refractory materials, hydraulic structures, thin shells, armor for jetties, rock slope stabilization, tunnel linings, and precast units.
• Explain about porous concrete commonly used where either free drainage is required or where lower mass and lower thermal conductivity are required.
• Describe the use of silica fume as a pozzolan in concrete which can enhance certain properties of both fresh and hardened concrete including cohesiveness, strength, and durability, and may be appropriate for concrete applications which require very high strength, high abrasion resistance, very low permeability, or where very cohesive mixtures are needed to avoid segregation. 

Benefit for Attendee:
This course will give Civil and Structural Engineers and Construction Managers an introduction to the design and construction of buildings and infrastructure employing special concretes.

Course Introduction:
This is an introduction to the design and construction factors to consider in utilizing special concretes on a variety of projects.

Course Summary:
This course will help you to employ special concretes in the design and construction of many different projects and applications.

An Introduction to Concrete Structures Repair Part I

Course Description:
This discussion contains descriptions of various materials and methods that are available for repair or rehabilitation of concrete structures. Each of the entries in this chapter will include description, applications and limitations, and procedure. Although the repair procedures given in this chapter are current practice, they may not be used directly in project specifications because each repair project may require unique remedial action.  This is the first of two courses on this topic. 

Course Outline:
1. INTRODUCTION
2. ADDITIONAL REINFORCEMENT
3. AUTOGENOUS HEALING
4. CONVENTIONAL CONCRETE PLACEMENT
5. CRACK ARREST TECHNIQUES
6. DRILLING AND PLUGGING
7. DRYPACKING
8. FIBER-REINFORCED CONCRETE
9. FLEXIBLE SEALING
10. GRAVITY SOAK
11. GROUTING (CHEMICAL)
12. GROUTING (HYDRAULIC-CEMENT)
13. HIGH-STRENGTH CONCRETE
14. JACKETING
15. JUDICIOUS NEGLECT
16. OVERLAYS (POLYMER)
17. OVERLAYS (PORTLAND-CEMENT)

Learning Objectives:
At the conclusion of this course, the student will be able to:

• Explain how cracked reinforced concrete bridge girders have been successfully repaired by use of additional conventional reinforcement.
• Explain the importance of concrete elements may be reinforced externally by the placement of longitudinal reinforcing bars and stirrups or ties around the members and then encasing the reinforcement with shotcrete or cast-in-place concrete.
• Delineate how cracks in slabs on grade may be repaired by making saw cuts across the crack and extending on either side of the crack, filling the saw cuts and the crack with epoxy, and forcing a steel plate of appropriate size into each saw cut.
• Select between the crack arrest techniques that may be used during the construction of a massive concrete structure to stop crack propagation into subsequent concrete lifts.
• Describe the importance of Drypacking, which is a process of ramming or tamping into a confined area a low water-content mortar. Because of the low w/c material, there is little shrinkage, and the patch remains tight and is of good quality with respect to durability, strength, and water tightness. 

Benefit for Attendee:
This course will give Civil and Structural Engineers and Construction Managers an introduction to the materials and methods that may be used to make repairs to cracked and deteriorated concrete structures. 

Course Introduction:
This is an introduction to the methods and materials that may be employed in making a selection of concrete structure repairs.

Course Summary:
After completion of this course, you will be prepared to consider and evaluate repair methods for damaged and deteriorated concrete structures.