8/3/2019 Bcn 5905 Concrete
1/55
BCN 5905STRUCTURES I
Dr. Larry Muszynski
RNK 327
8/3/2019 Bcn 5905 Concrete
2/55
Theme for the Class
Steel rusts,
Wood rots, but
Concrete is forever!!!!!!!!!!!But unfortunately, we sometimes make
concrete forms out of Timber
8/3/2019 Bcn 5905 Concrete
3/55
Class Structure
30 - 75 minute periods.
20 lectures, three exams, lab, two or three take
home assignments and a Field trip?
8/3/2019 Bcn 5905 Concrete
4/55
Course Outline
Fundamentals and Properties of Concrete
Concrete Construction
Timber and Formwork
8/3/2019 Bcn 5905 Concrete
5/55
There is No such Animal as aCement @$&!*^#%
Composition of Concrete
PC + Water + Aggregates (FA & CA) + Porosity
Heterogeneous and isotropic
Wood is homogeneous and non-isotropic
Steel is homogeneous and isotropic
1 cu.ft. weighs 94 #Properties of Fresh Concrete and Hardened
Concrete
8/3/2019 Bcn 5905 Concrete
6/55
Fresh Properties
Slump
Temperature
Density & Yield
Air Content
Time of Setting
8/3/2019 Bcn 5905 Concrete
7/55
Hardened Properties
Strength
Air Content
Density, Absorption and Voids
Heavy ~ 150 pcf or about 2 tons pcy
Volume Change
Durability
Permeability
8/3/2019 Bcn 5905 Concrete
8/55
How does Concrete Get ItsStrength
PC + water = hydration reaction > GLUE + Heat
Cementitious material literally glues all of the
inert (non-reactive) aggregates together toproduce a solid load bearing mass that we call
PCC
Strength is inversely proportional to the water-to-cement ratio
8/3/2019 Bcn 5905 Concrete
9/55
Strength vs. w/c Ratio for PCC
Strength,psi
w/c ratio
8/3/2019 Bcn 5905 Concrete
10/55
Whats Important
Good quality materials
PC, water, coarse aggregate, and fine aggregate
Proper Proportioning of the Materials
Proper Mixing
Placing and Finishing
Proper Curing
QC Testing
8/3/2019 Bcn 5905 Concrete
11/55
How about the Costs?
Item % of Total Cost
Concrete Materials 24%
Labor & Equipment 8%
Reinforcing Steel 12%
Labor & Equipment 7%
Formwork Materials 10%
Labor & Equipment 39%
8/3/2019 Bcn 5905 Concrete
12/55
Other Types of Concrete
Lightweight Concrete
Structural and Non-structural (120 50 pcf)
High Density Concrete (400 pcf)
Mass Concrete
Pre-placed Concrete
No Slump ConcreteRoller-Compacted Concrete
Shotcrete (Wet and Dry)
8/3/2019 Bcn 5905 Concrete
13/55
PC does NOT come from PortlandOregon
Portland Cement
Limestone + Sand + Clay + Iron ore + heat(1500 C)
= PC Clinker + Grinding = PC powder Dry process and wet process
Hydraulic Cement hardens in air and under water
Types I, II, III, IV and V IA and IIA blended with air-entraining agents
White Portland Cement
8/3/2019 Bcn 5905 Concrete
14/55
Blended Cements
Blended Cements
Type IP or P Portland Pozzolan Cement
Moderate heat and moderate sulfate resistance Class C Fly Ash 15 to 40%
Class F Fly Ash 15 to 25% (FDOT)
Type IS or S - Portland Blast Furnace Slag Cement
Low Heat (FDOT)
25 70%
8/3/2019 Bcn 5905 Concrete
15/55
Other Cements
Masonry Cement (mortar)Types N, S and M (See Table next slide)
Expansive Cements Type K High Early Strength Cements - RR
Calcium SulfoaluminateRapid Set
Calcium Aluminate Cements- Cement Fondu
Magnesium PhosphateSET-45 Oil-Well Cements
Acid Resistant CementsSilicate based
Sulfur
8/3/2019 Bcn 5905 Concrete
16/55
Mixing Water
Potable
ie. Water suitable for drinking
Chloride < 0.05%
Sulfate < 0.08%
Organic salts < 0.05%
sugar
8/3/2019 Bcn 5905 Concrete
17/55
Aggregates
Coarse Aggregate
Retained on #4 Sieve
Igneous, Sedimentary and Metamorphic rock Granite
Limestone
River gravel
8/3/2019 Bcn 5905 Concrete
18/55
CA continued
Maximum size from 6-in to 3/8-in
Max size governed by ACI code
Slab, form size and/or reinforcement
Graded down to #4 sieve according to ASTM C136
Common gradations, 467, 57, 67 and 89
1-1/2 in max, 1-in max, -in max, and 3/8-in max respectively
8/3/2019 Bcn 5905 Concrete
19/55
Aggregates
Fine Aggregate
Passing #4 Sieve ~ -in.
Natural Siliceous and Crushed LimestoneGraded according to ASTM C33
See next slide
Fineness modulus
Indication of the average particle size (2.0 to 3.0)
8/3/2019 Bcn 5905 Concrete
20/55
Fine Aggregate Grading Limits
Sieve size % Passing
No. 4 95-100
No. 8 80-100
No. 16 50-85
No. 30 25-60
No. 50 5-30
No. 100 0-10
8/3/2019 Bcn 5905 Concrete
21/55
Fine Aggregate Limits
Sieve Size
% Passing
8/3/2019 Bcn 5905 Concrete
22/55
Recycled Concrete Aggregate
Old concrete that has been removed and
crushed to produce aggregate.
Coarse aggregate in new concrete
Fine aggregate in new concrete
Best combination is CA with natural fine aggregate
Good strength
Drying shrinkage problem
Base-coarse replacement for natural limestone
8/3/2019 Bcn 5905 Concrete
23/55
Mineral Admixtures
Pozzolanic (cement replacement)
Class C Fly ash15 to 40% bwc
Class F Fly ash 15 to 25% bwcBlast Furnace Slag (cement replacement)
25 to 70% bwc
Silica Fume (cement addition)
6 to 12% bwc
8/3/2019 Bcn 5905 Concrete
24/55
Chemical Admixtures
ASTM C-494 and Table 6-1
Water Reducing Type A
Set Retarding Type B Set Accelerating Type C
Water Reducer-Set Retarding Type D
Water Reducer-Accelerating Type E High Range Water Reducers Type F
HR Water Reducer-Set Retarding -Type G
8/3/2019 Bcn 5905 Concrete
25/55
Air-Entraining Agents
ASTM C260
Admix that produces stable bubble system
Liquid and solidLow dosage rates relative to other chemical
admixtures (0.005 to 0.05% bwc).
Increase in durability @freeze/thawReduces compressive strength
5% per percent of entrained air
8/3/2019 Bcn 5905 Concrete
26/55
Fibers
Steel
Individual and bundled
Glassalkali attackSynthetic 1 to 1.5 lb per cu. yd.
polypropylene
nylonNaturalEgyptian pyramids
Straw, bamboo, and wood
8/3/2019 Bcn 5905 Concrete
27/55
Concrete Building Systems
Beam and Girder Floor system
Composite construction with Steel Beams
One-way joist floor
Flat Slabs
Flat Plate slabs
Two-way joist floor
Precast and Prestressed concrete
Connections
8/3/2019 Bcn 5905 Concrete
28/55
8/3/2019 Bcn 5905 Concrete
29/55
8/3/2019 Bcn 5905 Concrete
30/55
8/3/2019 Bcn 5905 Concrete
31/55
8/3/2019 Bcn 5905 Concrete
32/55
8/3/2019 Bcn 5905 Concrete
33/55
8/3/2019 Bcn 5905 Concrete
34/55
8/3/2019 Bcn 5905 Concrete
35/55
8/3/2019 Bcn 5905 Concrete
36/55
8/3/2019 Bcn 5905 Concrete
37/55
8/3/2019 Bcn 5905 Concrete
38/55
8/3/2019 Bcn 5905 Concrete
39/55
8/3/2019 Bcn 5905 Concrete
40/55
8/3/2019 Bcn 5905 Concrete
41/55
8/3/2019 Bcn 5905 Concrete
42/55
8/3/2019 Bcn 5905 Concrete
43/55
8/3/2019 Bcn 5905 Concrete
44/55
8/3/2019 Bcn 5905 Concrete
45/55
8/3/2019 Bcn 5905 Concrete
46/55
8/3/2019 Bcn 5905 Concrete
47/55
8/3/2019 Bcn 5905 Concrete
48/55
8/3/2019 Bcn 5905 Concrete
49/55
8/3/2019 Bcn 5905 Concrete
50/55
8/3/2019 Bcn 5905 Concrete
51/55
8/3/2019 Bcn 5905 Concrete
52/55
8/3/2019 Bcn 5905 Concrete
53/55
8/3/2019 Bcn 5905 Concrete
54/55
8/3/2019 Bcn 5905 Concrete
55/55
Top Related