SECTION 03300
CAST-IN-PLACE CONCRETE
CAST-IN-PLACE CONCRETE
PART 1 - GENERAL
1.1
THE
REQUIREMENT
A. The CONTRACTOR
shall furnish all materials for cast-in-place concrete in
accordance with the provisions of this Section and shall form, mix,
place, cure, repair, finish, and do all other work as required to
produce finished concrete, in accordance with the requirements of the
Contract Documents.
B. Unless specifically
indicated otherwise in the Contract Documents, all concrete work,
including steel reinforcing, shall be in accordance with the best
standard practices as set forth in the ACI Building Code, Manuals and
Recommended Practices.
1.2
RELATED
WORK SPECIFIED ELSEWHERE
A. The requirements of
the following Specification sections and divisions apply to the Work
of this section. Other sections and divisions of the Specifications,
not referenced below, shall also apply to the extent required for
proper performance of this Work.
1. Section 03071,
Epoxies
2. Section 03100,
Concrete Formwork
3. Section 03123,
Controlled Density Concrete
4. Section 03200
Reinforcement Steel
5. Section 03290,
Joints in Concrete
6. Section 03350
Concrete Testing
7. Section 03366,
Tooled Concrete Finishes
8. Section 03600,
Grouts
9. Section 07130,
Concrete Sealer and Hardener
10. Section 07900, Joint
Sealants
1.3
REFERENCE
SPECIFICATIONS, CODES, AND STANDARDS
A. All Work specified
herein shall conform to or exceed the applicable requirements of the
referenced portions of the following publications to the extent that
the provisions thereof are not in conflict with other provisions of
these Specifications.
B. Comply with the
applicable editions of the following codes, regulations and
standards.
1. Industry Standards:
American Concrete
Institute (ACI):
318 Building
Code Requirements for Structural Concrete
350 Building
Code Requirements for Environmental Concrete
Structures Manual of
Concrete Practice Recommended Practices
ASTM International
(ASTM):
C 31 Practice
for Making and Curing Concrete Test Specimens in the
Field
C 33
Specification for Concrete Aggregates
C 39 Test
Method for Compressive Strength of Cylindrical Concrete
Specimens
C 40 Test
Method for Organic Impurities in Fine Aggregates for
Concrete
C 42 Method
of Obtaining and Testing Drilled Cores and Sawed
Beams of Concrete
C 88 Test
Method of Soundness of Aggregates by Use of Sodium
Sulfate or Magnesium
Sulfate
C 94
Specification for Ready-Mixed Concrete
C 114 Test
Methods for Chemical Analysis of Hydraulic Cement
C 131 Test
Method for Resistance to Degradation of Small-Size Coarse
Aggregate by Abrasion
and Impact in the Los Angeles Machine C 136 Test Method for
Sieve Analysis of Fine and Coarse Aggregates C 143 Test
Method for Slump of Hydraulic Cement Concrete
C 150
Specification for Portland Cement
C 157 Test
Method for Length Change of Hardened Hydraulic-Cement
Mortar and Concrete.
C 172 Practice
for Sampling Freshly Mixed Concrete
C 173 Test
Method for Air Content of Freshly Mixed Concrete by the
Volumetric Method
C 203 Test
Methods for Breaking Load and Flexural Properties of
Block-Type Thermal
Insulation
C 227 Test
Method for Potential Alkali Reactivity of Cement-Aggregate
Combinations (Mortar-Bar
Method)
C 260
Specification for Air-Entraining Admixtures for Concrete
C 289 Test
Method for Potential Alkali-Silica Reactivity of Aggregates
(Chemical Method)
C 309
Specification for Liquid Membrane-Forming Compounds for
Curing Concrete
C 311 Test
Methods for Sampling and Testing Fly Ash or Natural
Pozzolans for Use in
Portland-Cement Concrete
C 469 Test
Method for Static Modulus of Elasticity and Poisson's Ratio of
Concrete in Compression
C 494
Specification for Chemical Admixtures for Concrete
C 595M
Specification for Blended Hydraulic Cements
C 618
Specification for Coal Fly Ash and Raw or Calcined Natural
Pozzolan for Use in
Concrete
D 75 Practice
for Sampling Aggregates
1.4
DEFINITIONS
A. Alkali:
Is defined to mean sum of sodium oxide and potassium oxide
calculated as sodium oxide.
B. Hairline
Crack:
Crack with a crack width of less than 4 thousandths of an inch.
1.5
SYSTEM
DESCRIPTION
A. Performance
Requirements:
1. General:
a. Except as
otherwise specified, provide concrete composed of portland
cement, fine aggregate, coarse aggregate, and water so proportioned
and mixed as to produce plastic, workable mixture in accordance with
requirements as specified in this Section and suitable to specific
conditions of placement.
b. Proportion
materials in manner such as to secure lowest water-cement ratio
which is consistent with good workability, plastic, cohesive
mixture, and one which is within specified slump range.
c. Proportion fine and
coarse aggregate in manner such as not to produce harshness in
placing nor honeycombing in structures.
2. Watertightness
of Concrete Work:
It is intent of this Section to secure for every part of the
Work concrete and grout of homogeneous structure, which when
hardened will have required strength, watertightness, and
durability.
a. It is recognized
that some surface hairline cracks and crazing will develop in the
concrete surfaces.
b. Construction,
contraction, and expansion joints have been positioned in
structures as indicated on the Drawings, and curing methods
specified, for purpose of reducing number and size of these expected
cracks, due to normal expansion and contraction expected from
specified concrete mixes.
c. Class
A, Class B, and Class D Concrete:
Watertight: Repair cracks which develop in walls or slabs and
repair cracks which show any signs of leakage until all leakage is
stopped.
d. Pressure inject
visible cracks, other than hairline cracks and crazing, in following
areas with epoxy as specified in Section 03931, Epoxy
Injection System.
1) Floors and walls of
water bearing structures.
2) Walls and overhead
slabs of passageways or occupied spaces, outsides of which are
exposed to weather or may be washed down and are not specified to
receive separate waterproof membrane.
3) Other
Items Not Specified to Receive Separate Waterproof Membrane:
Slabs over water channels, wet wells, reservoirs, and other similar
surfaces.
e. Walls or slabs, as
specified above, that leak or sweat because of porosity or cracks
too small for successful pressure grouting: Seal on water or weather
side by coatings of surface sealant system, as specified in this
Section.
f. Grouting
and Sealing:
Continue as specified above until structure is watertight
and remains watertight for not less than one year after
final acceptance or date of final repair, whichever occurs later in
time.
3. Workmanship
and Methods:
Provide concrete work, including detailing of reinforcing,
conforming with best standard practices and as set forth in ACI 318,
Manuals, and Recommended Practices.
1.6
SUBMITTALS
A. Submittals shall be
made in accordance with the General Requirements, Additional
General
Requirements and as specified herein.
B. Product
Data:
Submit data completely describing products.
C. Information
on Heating Equipment to Be Used for Cold Weather Concreting:
Submit information on type of equipment to be used for heating
materials and/or new concrete in process of curing during
excessively cold weather.
D. For conditions that
promote rapid drying of freshly placed concrete such as low
Humidity, high temperature, and wind: Submit corrective measures
proposed for use prior to placing concrete.
E. Copies
of Tests of Concrete Aggregates:
Submit certified copies in triplicate of commercial laboratory
tests of all samples of concrete aggregates.
1. Fine Aggregate: a.
Clay lumps. b. Reactivity.
c. Shale and chert. d.
Soundness.
e. Color.
f. Decantation.
2. Coarse Aggregate:
a. Clay lumps and
friable particles. b. Reactivity.
c. Shale and chert. d.
Soundness.
e. Abrasion loss.
f. Coal and ignite.
g. Materials finer
than 200 sieve.
F. Sieve
Analysis:
Submit sieve analyses of fine and coarse aggregates being used in
triplicate at least every 3 weeks and at any time there is
significant change in grading of materials.
G. Concrete
Mixes:
Submit full details, including mix design calculations for concrete
mixes proposed for use for each class of concrete.
1. Include information
on correction of batching for varying moisture contents of fine
aggregate.
2. Submit source
quality test records with mix design submittal.
a. Include
calculations for f'cr based on source quality test records.
H. If there is change
in aggregate source, or aggregate quality from same source, submit
new set of design mixes covering each class of concrete.
I. Test Batch Test
Data:
1. Submit data for
each test cylinder.
2. Submit data that
identifies mix and slump for each test cylinder.
J. Sequence
of Concrete Placing:
Submit proposed sequence of placing concrete showing proposed
beginning and ending of individual placements.
K. Curing
Compound Other than Specified Compound:
Submit complete data on proposed compound.
L. Repair
of Defective Concrete:
Submit mix design for grout.
M. Acceptance
of Method of Concrete Repair:
Make no repair until the ENGINEER has accepted method of preparing
surfaces and proposed method of repair.
N. If either fine or
coarse aggregate is batched from more than one bin, submit analyses
for each bin, and composite analysis made up from these, using
proportions of materials to be used in mix.
O. Cement
Mill Tests:
Include alkali content, representative of each shipment of cement
for verification of compliance with specified requirements.
P. Pozzolan
Certificate of Compliance:
Identify source of pozzolan and certify compliance with
requirements of ASTM C 618.
Q. Information on
mixing equipment. R. Drying shrinkage test data.
1.7
DELIVERY,
STORAGE, AND HANDLING A. Packing and Shipping:
1. Deliver, store, and
handle concrete materials in manner as to prevent damage and
inclusion of foreign substances.
2. Deliver and store
packaged materials in original containers until ready for use.
3. Deliver aggregate
to mixing site and handle in such manner that variations in moisture
content will not interfere with steady production of concrete of
specified degree of uniformity and slump.
B. Acceptance
at Site:
Reject material containers or materials showing evidence of water
or other damage.
1.8
PROJECT
CONDITIONS
A. Environmental
Requirements:
1. Hot Weather
Concreting:
a. When
Ambient Air Temperature Is above 90 degrees F:
Prior to placing concrete, cool forms and reinforcing steel to
by water cooling to below
90 degrees F.
b. Temperature
of Concrete Mix at Time of Placement:
Keep temperature below 90 degrees F by methods which do not impair
quality of concrete.
2. Cold Weather
Concreting:
a. Concrete placed
below ambient air temperature of 45 degrees F and falling or below
40 degrees F, make provision for heating water.
b. If materials have
been exposed to freezing temperatures to degree that any material is
below 35 degrees F, heat such materials.
c. Heating Water,
Cement, or Aggregate Materials:
1) Do not heat in
excess of 160 degrees F.
2) Protection of
Concrete in Forms:
3) Protect by means
of covering with tarpaulins, or other acceptable covering.
4) Provide means for
circulating warm moist air around forms in manner to maintain
temperature of 50 degrees F for at least 5 days.
3. For conditions that
promote rapid drying of freshly placed concrete such as low
humidity, high temperature, and wind, take corrective measures to
minimize rapid water loss from concrete.
a. Furnish and use
sufficient number of maximum and minimum self-recording thermometers
to adequately measure temperature around concrete.
1.9
SEQUENCING
AND SCHEDULING
A. Schedule placing of
concrete in such manner as to complete any single placing operation
to construction, contraction, or expansion joint.
PART 2 - PRODUCTS
2.1
MATERIALS
A. Aggregate:
1. General:
a. Provide concrete
aggregates that are sound, uniformly graded, and free of deleterious
material in excess of allowable amounts specified.
b. Grade aggregate in
accordance with ASTM D 75 and C 136.
c. Provide unit weight
of fine and coarse aggregate which produces in place concrete with
weight of not less than 140 pounds per cubic foot.
B. Fine Aggregate:
1. Provide fine
aggregate for concrete or mortar consisting of clean, natural sand
or of sand prepared from crushed stone or crushed gravel.
2. Do not provide
aggregate having deleterious substances in excess of following
percentages by weight of contaminating substances. In no case shall
total exceed percent listed.
- ItemTest MethodPercentRemoved by decantation (dirt, silt, etc.)ASTM C 1173Shale or ChertASTM C 2951Clay LumpsASTM C 1421
3. Except as
otherwise specified, grade fine aggregate from coarse to fine
in accordance with requirements of ASTM C 33.
C. Coarse Aggregate:
1. General:
Provide coarse aggregate consisting of gravel or crushed stone made
up of clean, hard, durable particles free from calcareous coatings,
organic matter, or other foreign substances.
2. Weight:
Not exceeding 15 percent, for thin or elongated pieces having
length greater than 5 times average thickness.
3. Deleterious
Substances:
Not in excess of following percentages by weight, and in no case
having total of all deleterious substances exceeding 2 percent.
- ItemTest MethodPercentShale or chertASTM C 2951Coal and ligniteASTM C 1231/4Clay lumps and friable particlesASTM C 1421/4Materials finer than Number 200 sieveASTM C 1171/2**Except when material finer than Number 200 sieve consists of crusherdust, maximum amount shall be 1 percent.
4. Grading:
a. Aggregate:
As specified in ASTM C 33, Size Number 57, except as
otherwise specified or authorized in writing by the ENGINEER.
b. Aggregate for Class
CE Concrete for Encasement of Electrical Conduits: (1) Graded as
specified in ASTM C 33, Size Number 8.
(2) Provide concrete
utilizing this aggregate equal to Class C concrete in all other
respects, and is designated as Class CE.
D. Portland Cement:
1. General:
Conform to specifications and tests for ASTM C 150, Types II,
III, sulfate resisting Type V, Low Alkali, except as specified
otherwise.
2. Low
Alkali Portland:
Have total alkali containing not more than 0.60 percent.
3. Exposed
Concrete in Any Individual Structure:
Use only one brand of portland cement.
4. Cement
for Finishes:
Provide cement from same source and of same type as concrete to be
finished.
E. Admixtures:
1. General:
a. Do not use
admixtures of any type, except as specified, unless written
authorization has been obtained from the ENGINEER.
b. Compatible with
concrete and other admixtures.
c. Do not use
admixtures containing chlorides calculated as chloride ion in excess
of 0.5 percent by weight.
d. Use in accordance
with manufacturer's recommendations and add each admixture to
concrete mix separately.
2. Air Entraining
Admixture:
a. Provide all
concrete with 5 percent, plus or minus 1 percent, entrained air of
evenly dispersed air bubbles at time of placement.
b. Conform to ASTM C
260.
3. Fly Ash Pozzolan
Admixture:
a. Pozzolan:
(1) Conforming to
requirements of ASTM C 618, Class F, may be used as admixture in
concrete made with Type II Portland cement.
(2) Pozzolan may
replace portland cement at ratio of 1.0 pound fly ash for each pound
of portland cement replaced.
(3) Maximum of 15
percent by weight of minimum quantities of portland cement listed
in Table A under paragraph 2.03E may be replaced with
pozzolan.
(4) Do not use pozzolan
as an admixture in concrete made with portland- pozzolan cement.
b. Loss
on Ignition for Pozzolan:
Not exceed four percent.
4. Water Reducing
Admixture:
a. May be used at the
CONTRACTOR's option. b. Conform to ASTM C 494, Type A or Type D.
c. Not contain air entraining agents.
d. Liquid form before
adding to the concrete mix.
e. No decrease in
cement is permitted as result of use of water reducing
admixture.
5.
Superplasticizers:
Are not to be used without acceptance by ENGINEER.
F. Water:
1. Water
for Concrete, Washing Aggregate, and Curing Concrete:
Clean and free from oil and deleterious amounts of alkali, acid,
organic matter, or other substances.
2. Chlorides and
Sulfate Ions:
a. Water
for Conventional Reinforced Concrete:
Use water not containing more than 1,000 milligrams per liter of
chlorides calculated as chloride ion, nor more than 1,000 milligrams
per liter of sulfates calculated as sulfate ion.
b. Water
for Prestressed or Post-tensioned Concrete:
Use water not containing more than 650 milligrams per liter of
chlorides calculated as chloride ion, nor more than 800 milligrams
per liter of sulfates calculated as sulfate ion.
G. Nonslip Abrasive:
1. Type:
Aluminum oxide abrasive of size 8/16, having structure of hard
aggregate, homogenous, nonglazing, rustproof, and unaffected by
freezing, moisture, or cleaning compounds.
2. Manufacturers:
One of the following, Or Equal:
a. Exolon
Company, Tonawanda, New York.
b. Abrasive Materials,
Incorporated, Hillsdale, Michigan.
H. Concrete Sealer:
1. Manufacturers:
One of the following, Or Equal:
a. Hillyard
Chemical Company, St. Joseph, Missouri, SEAL 341.
b. A. C. Horn, Inc.,
Horn Clear Seal EM-180. I. Conduit Encasement Coloring Agent:
1. Color:
Red color concrete used for encasement of electrical ducts,
conduits, similar type items.
2. Manufacturers:
One of the following, Or Equal.
a. Frank D. Davis
Company, Red Oxide Number 1117.
b. I. Reiss Company,
Inc., equivalent product.
J. Keyway
Material:
Steel, plastic, or lumber.
K. Sprayed
Membrane Curing Compound:
Clear type with fugitive dye conforming to
ASTM C 309, Type
1D.
L. Surface
Sealant System:
Manufacturers: One of the following, Or Equal:
1. Radcon
Laboratories, Inc., Las Vegas, Nevada, Formula Number 7.
2. IPA Systems,
Philadelphia, Pennsylvania, Duripal.
2.2
EQUIPMENT
A. Mixing Concrete:
1. Mixers may be of
stationary plant, paver, or truck mixer type.
2. Provide adequate
equipment and facilities for accurate measurement and control of
materials and for readily changing proportions of material.
3. Mixing Equipment:
a. Capable of
combining aggregates, cement, and water within specified time into
thoroughly mixed and uniform mass and of discharging mixture
without segregation.
b. Maintain concrete
mixing plant and equipment in good working order and operated at
loads, speeds, and timing recommended by manufacturer or as
specified.
c. Proportion cement
and aggregate by weight. B. Machine Mixing:
1. Batch plant shall
be capable of controlling delivery of all material to mixer within
1 percent by weight of
individual material.
2. If bulk cement is
used, weigh it on separate visible scale which will accurately
register scale load at any stage of weighing operation from zero to
full capacity.
3. Prevent cement from
coming into contact with aggregate or with water until materials are
in mixer ready for complete mixing with all mixing water.
4. Procedure of mixing
cement with sand or with sand and coarse aggregate for delivery to
project site, for final mixing and addition of mixing water will not
be permitted.
5. Retempering of
concrete will not be permitted.
6. Discharge entire
batch before recharging.
7. Volume
of Mixed Material Per Batch:
Not exceed manufacturer's rated capacity of mixer.
8. Mixers:
a. Perform mixing in
batch mixers of acceptable type.
b. Equip each mixer
with device for accurately measuring and indicating quantity
of water entering concrete, and operating mechanism such that
leakage will not occur when valves are closed.
c. Equip each mixer
with device for automatically measuring, indicating, and controlling
time required for mixing.
(1) Interlock device
to prevent discharge of concrete from mixer before expiration
of mixing period.
C. Transit-mixed
Concrete:
1. Mix and deliver in
accordance with ASTM C 94.
2. Total Elapsed Time
Between Addition of Water at Batch Plant and Discharging Completed
Mix: Not to exceed 90 minutes or elapsed time at project site shall
not exceed 30 minutes.
3. Under conditions
contributing to quick setting, total elapsed time permitted may be
reduced by the ENGINEER.
4. Equip each truck
mixer with device interlocked so as to prevent discharge of concrete
from drum before required number of turns and furnish such device
that is capable of counting number of revolutions of drum.
5. Continuously
revolve drum after it is once started until it has
completely discharged its batch.
a. Do not admit water
until drum has started revolving.
b. Right is reserved
to increase required minimum number of revolutions or to decrease
designated maximum number of revolutions allowed, if necessary, to
obtain satisfactory mixing. The CONTRACTOR will not be entitled to
additional compensation because of such increase or decrease.
D. Other Types of
Mixers:
1. In Case of Other
Types of Mixers, Mixing Shall Be as Follows:
a. Mix concrete until
there is uniform distribution of materials, and discharge mixer
completely before recharging.
b. Neither speed nor
volume loading of mixer shall exceed manufacturer's
recommendations.
c. Continue mixing for
minimum of 1-1/2 minutes after all materials are in drum, and for
batches larger than one cubic yard increase minimum mixing
time
15 seconds for each
additional cubic yard or fraction thereof.
2.3
MIXES
A. Measurements of
Materials:
1. Measure materials
by weighing, except as otherwise specified or where other methods
are specifically authorized in writing by the ENGINEER.
2. Furnish apparatus
for weighing aggregates and cement that is suitably designed and
constructed for this purpose.
3. Accuracy
of Weighing Devices:
Furnish devices that have capability of providing successive
quantities of individual material that can be measured to
within one percent of desired amount of that material.
4. Measuring
or Weighing Devices:
Subject to review by the ENGINEER, and bear valid seal of the
Sealer of Weights and Measures having jurisdiction.
5. Weighing Cement:
a. Weigh cement
separately.
b. Cement
in Unbroken Standard Packages (Sacks):
Need not be weighed. c. Bulk
Cement and Fractional Packages:
Weigh such cement.
6. Mixing
Water:
Measured by volume or by weight.
B. Concrete
Proportions and Consistency:
1. Concrete
Consistency and Composition:
a. Provide concrete
that can be worked readily into corners and angles of forms and
around reinforcement without excessive vibration and without
permitting materials to segregate or free water to collect on
surface.
b. Prevent unnecessary
or haphazard changes in consistency of concrete.
2. Ratio
of Coarse Aggregate to Fine Aggregate:
Not less than 1.0 nor more than
2.0
for all concrete Classes, with exception of Class CE.
3. Aggregate:
a. Obtain aggregate
from source which is capable of providing uniform quality, moisture
content, and grading during any single day's operation.
4. Concrete Mix Water
to Cement Ratio, Minimum Cement Content, and Slump
Range:
Conform to values specified in Table A in this section.
5. Concrete
Batch Weights:
Control and adjust so as to secure maximum yield, and at all times
maintain proportions of concrete mix within specified limits.
6. Mixture
Modification:
If required, by the ENGINEER, modify mixture within limits set
forth in this section.
C. Concrete Mixes:
1. Proportioning
of Concrete Mix:
Proportion mixes on required average on compressive strength
f'cr as defined in Subparagraph 2.4A2.
2. Mixes:
a. Adjusting
of Water:
After acceptance, do not change mixes without acceptance
by ENGINEER, except that at all times adjust batching of water to
compensate for free moisture content of fine aggregate.
b. Total
Water Content of Each Concrete Class:
Not exceed those specified in
Table A in this
section.
c. Checking
Moisture Content of Fine Aggregate:
Furnish satisfactory means at batching plant for checking moisture
content of fine aggregate.
3. Change
in Mixes:
Undertake new trial batch and test program as specified in this
section.
D. Hand Mixed Concrete:
1. Hand mix concrete
only when acceptable to the ENGINEER.
2. Prepare hand mixed
concrete on watertight, level platform in batches not to exceed 1/3
cubic yard each.
3. Aggregate:
a. First spread
required amount of coarse aggregate on platform in an even and
uniform layer, and then over such aggregate spread proper proportion
of fine aggregate.
b. Combined
Depth of Both Such Layers:
Not be greater than one foot.
4. Cement:
a. First evenly spread
required quantity of cement over fine aggregate.
b. Then turn entire
batch with shovels at least twice before adding water.
5. Water:
a. Then uniformly
sprinkle or spray proper amount of water over batched
materials.
b. Then turn with
shovels not less than three times before being removing from
platform.
E. Classes of
Concrete:
1. Provide concrete
consisting of 5 classes, referred herein as Classes A, B, C, D, and
CE specified in this section and use where specified or
indicated on the Drawings.
2. Weight
of Concrete Classes:
Provide classes of concrete having minimum weight of 140 pounds
per cubic foot. Where indicated as structural lightweeight, provide
concrete with a weight of 120 pounds per cubic foot.
3. Class
B Concrete:
Class B concrete may be substituted for Class A concrete, when
high-early strength concrete is needed in areas specifically
accepted by the ENGINEER and that do not require sulfate resistant
concrete.
4. Class
C Concrete:
Class C concrete may be used for fill for unauthorized
excavation, for thrust blocks and ground anchors for piping, for
bedding of pipe, and where indicated on the Drawings.
5. Class
D Concrete:
Use Class D for precast concrete items. Use Class D for liquid
containment structures and basement walls per general structural
notes.
6. Class
CE Concrete:
Use Class CE for electrical conduit encasements.
7. All
other concrete, unless specified or otherwise indicated on the
Drawings:
Use
Class A concrete.
Table A
Concrete
With Air
Entrainment
|
||||
Class
|
Specified
Compressive Strength f'c at 28 Days (Pounds per Square Inch)
|
Maximum Net Water
to Cement Ratio
|
M inimum Cement
per Cubic Yard of Concrete by Weight (Pounds)
|
Slump Range
(Inches)
|
A
|
4,000
|
0.45
|
564
|
2
to 4*
|
B (Type III cement)
|
4,000
4,000
lightweight
|
0.45
|
564
|
2
to 4*
|
C
|
2,500
|
0.62
|
423
|
3
to 6
|
D
|
4,500
or 5,000
|
0.45
|
658
|
2
to 4
|
CE
|
2,500
|
0.62
|
564
|
3
to 6
|
*
NOTE: Slump for slabs, decks, walks, and beams shall be not
more than 3-1/2 inches.
|
||||
8. Pumped
Concrete:
Provide pumped concrete that complies with all requirements of this
section.
9. Do not place
concrete with slump outside limits indicated in Table A.
10. Classes:
a. Classes
A, C, D, and CE Concrete:
Make with Type II low alkali cement. b. Class
B Concrete:
Make with Type III low alkali cement.
c. Admixtures:
Provide admixtures as specified in this section.
F. Air Entraining
Admixture:
1. Add agent to batch
in portion of mixing water.
2. Batch solution
by means of mechanical batcher capable of accurate
measurement.
2.4
SOURCE
QUALITY CONTROL A. Tests:
1. Concrete Mixes:
a. After concrete
mixes have been accepted by ENGINEER, have trial batches of the
accepted Class A, Class B, and Class D concrete mix designs prepared
by testing laboratory acceptable to the ENGINEER.
b. Prepare trial
batches by using specified cement and aggregates proposed to be used
for the Work.
c. Trial
Batches:
Provide batches of sufficient quantity to determine slump,
workability, consistency, and finishing characteristics, and to
provide sufficient test cylinders.
d. Test
Cylinders:
Provide cylinders having six inch diameter by 12 inch length and
that are prepared in accordance with ASTM C 31 for tests specified
in this section.
e. Determine slump in
accordance with ASTM C 143. f. Test Cylinders from Trial Batch:
1) Test 8
cylinders for compressive strength in accordance with
ASTM C 39.
a) Test 4 cylinders at
7 days and 4 at 28 days.
b) Establish ratio
between 7-day and 28-day strength for mix. Seven day
strength may be taken as satisfactory indication of 28-day strength
provided effects on concrete of temperature and humidity between
7-day and 28-day are taken into account.
2) Average Compressive
Strength of 4 Test Cylinders Tested At 28 Days: Equal to or greater
than required average compressive strength f'cr on which concrete
mix design is based.
g. Drying Shrinkage:
1) Prepare 5 drying
shrinkage specimens in accordance with ASTM C 157, except as
modified herein.
2) Remove drying
shrinkage specimens from molds at age of 23 hours plus or minus 1
hour after trial batching, then immediately place them in water at
73 degrees F plus or
minus 3 degrees for at least 30 minutes and then measure specimens
within 30 minutes thereafter to determine original length. Then
submerge specimens in saturated lime water at 73 degrees F plus or
minus three degrees for moist curing.
3) Make measurement to
determine expansion expressed as percentage of original length at
age 7 days. Use length at age 7 days as base length for drying
shrinkage calculations.
4) Immediately store
specimens in humidity controlled room maintained at
73 degrees F plus or
minus 3 degrees and 50 percent plus or minus
4 relative humidity for
remainder of test.
5) Make and report
measurements to determine shrinkage expressed as percentage of base
length separately for 7, 14, 21, and 28 days of drying after 7 days
of moist curing.
6) Drying Shrinkage
Deformation:
a) Measure drying
shrinkage deformation of each specimen as difference between
base length and length after drying at each test age.
b) Measure average
drying shrinkage deformation of specimens to nearest 0.0001 inch at
each test age.
c) If drying shrinkage
of any specimen departs from average of test age by more than 0.0004
inch, disregard results obtained from that specimen and test another
specimen.
d) Shrinkage of trial
batch concrete at 28 days drying age shall not exceed 0.045 percent
maximum.
h. If trial batch
tests do not meet specified requirements for slump, strength,
workability, consistency, drying shrinkage, and finishing, change
concrete mix design proportions and, if necessary, source of
aggregate. Make additional trial batches and tests until an
acceptable trial batch is produced that meets requirements of this
section.
i. Perform test
batches and tests required to establish trial batches and
acceptability of materials without change in Contract Price.
j. Do not place
concrete until the concrete mix design and trail batch have been
accepted by ENGINEER.
2. Required Average
Compressive Strength:
a. Determine required
average compressive strength (f'cr) for selection of concrete
proportions for mix design, for each class of concrete, using
calculated standard deviation and its corresponding specified
compressive strength f'c, in accordance with ACI 318, Part 3,
Chapter 5.
b. When test records
of at least 30 consecutive tests that span period of not less than
45 calendar days are available, establish standard deviation
as described in ACI 318, Part 3, Chapter 5 and as modified as
follows herein.
c. Provide test
records from which to calculate standard deviation that
represent materials, quality control procedures, and conditions
similar to materials, quality control procedures, and conditions
expected to apply in preparation of concrete for the Work.
d. Provide changes in
materials and proportions within test records that are more
restricted than those for the Work.
e. Specified
Compressive Strength (f'c) of Concrete Used in Test Records: Within
1,000 pounds per square inch of that specified for the Work.
When lacking adequate
test records for calculation of standard deviation meeting
requirements, determine required average compressive strength f'cr
from following Table B.
Table B
|
|
Specified
Compressive
Strength f'c
(pounds per
square inch)
|
Required Average
Compressive Strength f'cr (pounds per square inch)
|
Less
than 3,000
|
f'c + 1,000
|
3,000
to 5,000
|
f'c + 1,200
|
Over
5,000
|
f'c + 1,400
|
3. Pozzolan:
a. Sampling and
Testing:
(1) Sample and test
pozzolan in accordance with ASTM C 311.
(2) In Computing Water
to Cement Ratio And Cement Content Per Cubic Yard Of Concrete:
Consider cement weight to be weight of portland cement plus 100
percent of weight of fly ash.
4. Aggregate:
a. Testing of concrete
aggregate is at CONTRACTOR's expense. b. Sieves:
1) Use sieves with
square openings for testing grading of aggregates.
2) Sieve
Analyses:
If sieve analyses indicate significant change in
materials, the ENGINEER may require that new mix design be submitted
and accepted before further placing of concrete.
c. Sample aggregate in
accordance with ASTM D 75 and C 136. d. Fine Aggregate:
1) Provide fine
aggregate not containing strong alkali nor organic matter which
gives color darker than standard color when tested in accordance
with ASTM C 40.
2) Provide aggregate
having soundness complying with requirements of
ASTM C 33 when tested in
accordance with ASTM C 88.
3) Provide aggregate
complying with reactivity requirements of ASTM C 33 when tested in
accordance with ASTM C 289.
e. Coarse Aggregate:
1) Soundness when
tested in accordance with ASTM C 88: Have loss not greater than 10
percent when tested with sodium sulfate.
2) Abrasion Loss: Not
exceed 45 percent after 500 revolutions when tested in accordance
with ASTM C 131.
3) Reactivity: Not
exceed limits specified in Appendix of ASTM C 33 when tested in
accordance with ASTM C 289.
f. Portland Cement:
1) Determination
Alkali Content: Determine by method set forth in
ASTM C 114.
PART 3 - EXECUTION
3.1
INSTALLATION
A. Conduit Encasement
Concrete: Mix into each cubic yard of concrete 10 pounds of coloring
agent.
B. Surface Sealant
System: Apply as recommended by manufacturer published instructions.
Where concrete continues to sweat or leak, apply additional coats of
surface sealant until the sweating or leaks stop.
C. Joints and Bonding:
1. As far as
practicable, construct concrete work as monolith.
2. Locations of
contraction, construction, expansion, and other joints are indicated
on the Drawings or as specified in this section.
3. For the Following
Structures:
a. Larger Structures.
1) Provide not less
than 7 days between placement of concrete in adjacent concrete wall
placements.
2) Place concrete for
slabs in checker board pattern with not less than 14 days between
placement of concrete in adjacent concrete slab placements for slabs
more than 3 feet thick.
3) Place concrete for
slabs in checker board pattern with not less than 7 days between
placement of concrete in adjacent concrete slab placements for slabs
less than 3 feet thick.
b. Tunnels.
1) Provide not less
than 7 days between placement of concrete in adjacent concrete wall
placements.
2) Place concrete for
slabs in checker board pattern with not less than
3 days between placement
of concrete in adjacent concrete slab placements.
4. Construction
Joints:
a. Where construction
joints are not indicated on the Drawings, provide slabs and walls
with construction joints at intervals not greater than 30 feet.
b. In order to
preserve strength and watertightness of structures, make no other
joints, except as authorized by the ENGINEER.
c. At construction
joints, thoroughly clean concrete of laitance, grease, oil, mud,
dirt, curing compounds, mortar droppings, or other
objectionable matter by means of heavy sandblasting, and wash
surfaces just prior to succeeding concrete placement.
d. At Horizontal
Joints: Immediately prior to resuming concrete placing
operations, thoroughly spread bed of grout not less than 1/2 inch in
thickness nor more than 1 inch in thickness over horizontal joint
surfaces.
5. Keyways in Joints:
a. Provide keyways in
joints as indicated on the Drawings.
b. Treat lumber
keyway material with form release coating, applied in
accordance with manufacturer's instructions.
c. Take special care
to ensure that concrete is well consolidated around and against
waterstops and that waterstops are secured in proper position.
6. Cleaning of
Construction Joints:
a. Wash construction
joints free of sawdust, chips, and other debris after forms are
built and immediately before concrete or grout placement.
b. Should formwork
confine sawdust, chips, or other loose matter in such manner
that it is impossible to remove them by flushing with water, use
vacuum cleaner for their removal, after which flush cleaned surfaces
with water.
c. Provide cleanout
hole at base of each wall and column for inspection and cleaning.
7. Expansion,
Contraction, and Construction Joints
a. Constructed where
and as indicated on the Drawings.
b. Waterstops,
Expansion Joint Material, Synthetic Rubber Sealing Compound, and
Other Similar Materials: As specified in Sections 03290, Joints in
Concrete and 07900, Joint Sealants.
8. Repair of Concrete:
Where it is necessary to repair concrete by bonding mortar or new
concrete to concrete which has reached its initial set, first coat
surface of set concrete with epoxy bonding agent as specified in
Section 03071, Epoxies.
D. Conveying and
Placing Concrete:
1. Convey concrete
from mixer to place of final deposit by methods which prevent
separation or loss of materials.
2. Use equipment for
chuting, pumping, and conveying concrete of such size and design as
to ensure practically continuous flow of concrete at delivery end
without separation of materials.
3. Design and use
chutes and devices for conveying and depositing concrete that direct
concrete vertically downward when discharged from chute or conveying
device.
4. Keep equipment
for conveying concrete thoroughly clean by washing and
scraping upon completion of any day's placement.
E. Placing Concrete:
1. Place no concrete
without prior authorization of the ENGINEER.
2. Do Not Place
Concrete Until:
a. Reinforcement is
securely and properly fastened in its correct position and loose
form ties at construction joints have been retightened.
b. Dowels, bucks,
sleeves, hangers, pipes, conduits, bolts, and any other
fixtures required to be embedded in concrete have been placed and
adequately anchored.
c. Forms have been
cleaned and oiled as specified.
3. Placement of
concrete in which initial set has occurred, or of
retempered concrete, will not be permitted.
4. Place no concrete
during rainstorms or high velocity winds.
5. Protect concrete
placed immediately before rain to prevent water from coming in
contact with such concrete or winds causing excessive drying.
6. Keep sufficient
protective covering on hand at all times for protection of concrete.
7. After acceptance,
adhere to proposed sequence of placing concrete, except when
specific changes are requested and accepted by the ENGINEER.
8. Notify the ENGINEER
in writing of readiness, not just intention, to place concrete in
any portion of the Work.
a. Provide this
notification in such time in advance of operations as the ENGINEER
deems necessary to make final inspection of preparations at location
of proposed concrete placing.
b. Place forms, steel,
screeds, anchors, ties, and inserts in place before notification of
readiness is given to the ENGINEER.
c. Depositing
Concrete:
1) Deposit concrete at
or near its final position to avoid segregation caused by rehandling
or flowing.
2) Do not deposit
concrete in large quantities in one place and work along forms with
vibrator or by other methods.
3) Do not drop
concrete freely into place from height greater than 5 feet.
4) Use tremies for
placing concrete where drop is over 5 feet.
5) Commence placement
of concrete on slopes, at bottom of slope.
9. Place concrete in
approximately horizontal layers not to exceed 24 inches in depth and
bring up evenly in all parts of forms.
10. Continue concrete
placement without avoidable interruption, in continuous
operation, until end of placement is reached.
11. If more than 20
minutes lapse prior to placement of new concrete over concrete
previously placed, reduce depth of layers being placed at one time,
and/or increase placing equipment, until it is possible to return
with placing operation to previously placed concrete within 20
minutes.
12. If concrete is to
be placed over previously placed concrete and more than
20 minutes have
elapsed, then spread layer of grout not less than 1/2 inch
in thickness nor more than 1 inch in thickness over surface before
placing additional concrete.
13. Placement of
Concrete for Slabs, Beams, or Walkways:
a. If cast
monolithically with walls or columns, do not commence until concrete
in walls or columns has been allowed to set and shrink.
b. Allow set time of
not less than one hour for shrinkage. F. Consolidating Concrete:
1. Place concrete with
aid of acceptable mechanical vibrators.
2. Thoroughly
consolidate concrete around reinforcement, pipes, or other shapes
built into the Work.
3. Provide
sufficiently intense vibration to cause concrete to flow and settle
readily into place and to visibly affect concrete over radius of at
least 18 inches.
4. Vibrators:
a. Keep sufficient
vibrators on hand at all times to vibrate concrete as placed.
b. In addition to
vibrators in actual use while concrete is being placed, have on hand
minimum 1 spare vibrator in serviceable condition.
c. Place no concrete
until it has been ascertained that all vibrating equipment,
including spares, are in serviceable condition.
5. Take special care
to place concrete solidly against forms so as to leave no voids.
6. Take every
precaution to make concrete solid, compact, and smooth, and if for
any reason surfaces or interiors have voids or are in any way
defective, repair such concrete in manner acceptable to the
ENGINEER.
G. Footings and Slabs
on Grade:
1. Do not place
concrete on ground or compacted fill until subgrade is in moist
condition acceptable to the ENGINEER.
2. If necessary,
sprinkle subgrade with water not less than 6 nor more than
20 hours in advance of
placing concrete.
3. If it becomes dry
prior to actual placing of concrete, sprinkle again, without forming
pools of water.
4. Place no concrete
if subgrade is muddy or soft. H. Loading Concrete:
1. Green Concrete:
a. No heavy loading of
green concrete will be permitted.
b. Green concrete is
defined as concrete with less than 100 percent of the specified
strength.
2. No backfill shall
be placed against concrete walls until the concrete has reached the
specified strength and the connecting slabs and bemas have been cast
and have reached the specified strength.
3. Use construction
methods, sequencing, and allow time for concrete to reach adequate
strength to prevent overstress of the concrete structure during
construction.
I. Curing Concrete:
1. General:
a. Cure concrete by
methods specified in this section. b. Cure concrete minimum of 7
days.
c. Cure concrete to be
painted with water or plastic membrane.
d. Do not use curing
compound on concrete surfaces that are to receive paint or upon
which any material is to be bonded.
e. Water cure or
plastic membrane cure concrete slabs which are specified to be
sealed by concrete sealer.
f. Cure other
concrete by water curing or sprayed curing membrane at the
CONTRACTOR's
option.
g. Floor slabs may be
cured using plastic membrane curing.
h. All liquid
containment structures shall be water-cured.
2. Water Curing:
a. Keep surfaces of
concrete being water cured constantly and visibly moist day and
night for period of not less than 7 days.
b. Each day forms
remain in place may count as 1 day of water curing.
c. No further curing
credit will be allowed for forms in place after contact has once
been broken between concrete surface and forms.
d. Do not loosen form
ties during period when concrete is being cured by leaving forms in
place.
e. Flood top of walls
with water at least 3 times per day, and keep concrete surfaces
moist at all times during 7-day curing period.
3. Sprayed Membrane
Curing:
a. Apply curing
compound to concrete surface after repairing and patching, and
within 1 hour after forms are removed.
b. If more than 1 hour
elapses after removal of forms, do not use membrane curing compound,
but apply water curing for full curing period.
c. If surface requires
repairing or painting, water cure such concrete surfaces. d.
Curing Compound:
1) Do not remove
curing compound from concrete in less than 7 days.
2) Curing compound may
be removed only upon written request by the CONTRACTOR and
acceptance by the ENGINEER, stating what measures are to be
performed to adequately cure structures.
3) Take care to apply
curing compound in area of construction joints to see that curing
compound is placed within construction joint silhouette.
4) Remove curing
compound placed within construction joint silhouette by heavy
sandblasting prior to placing any new concrete.
5) CONTRACTOR's
Option:
Instead of using curing compound for curing of construction joints
such joints may be water cured.
6) Apply curing
compound by mechanical, power operated sprayer and mechanical
agitator that will uniformly mix all pigment and compound.
7) Apply compound in
at least 2 coats.
8) Apply each coat in
direction 90 degrees to preceding coat.
9) Apply compound in
sufficient quantity so that concrete has uniform appearance and that
natural color is effectively and completely concealed at time of
spraying.
10) Continue to coat and
recoat surfaces until specified coverage is achieved and until
coating film remains on concrete surfaces.
11) Thickness
and Coverage of Compound:
Provide compound having film thickness that can be scraped from
surfaces at any and all points after drying for at least 24 hours.
12) The CONTRACTOR is
cautioned that method of applying curing compound specified
herein may require more compound than normally suggested by
manufacturer of compound and also more than is customary in the
trade.
a) Apply amounts
specified herein, regardless of manufacturer's recommendations or
customary practice, if curing compound is used in place of water
curing.
13) If the CONTRACTOR
desires to use curing compound other than specified compound,
coat sample areas of concrete wall with proposed compound and
also similar adjacent area with specified compound in specified
manner for comparison.
a) If proposed
sample is not equal or better, in opinion of the
ENGINEER, in all
features, proposed substitution will not be allowed.
14) Prior to final
acceptance of the Work, remove, by sandblasting or other acceptable
method, any curing compound on surfaces exposed to view, so that
only natural color of finished concrete is visible uniformly over
entire surface.
4. Plastic Membrane
Curing:
a. Polyethylene film
may be used to cure slabs. Seal joints and edges with small sand
berm.
b. Install plastic
membrane as soon as concrete is finished and can be walked on
without damage.
c. Keep concrete moist
under plastic membrane.
3.2
CONCRETE
FINISHING
A. Provide concrete
finishes in accordance with Section 03366, Tooled Concrete
Finishes, and the
Concrete Finish Schedule indicated on the Drawings.
B. Edges of Joints:
1. Provide joints
having edges as indicated on the Drawings.
2. Protect wall and
slab surfaces at edges against concrete spatter and thoroughly clean
upon completion of each placement.
C. Concrete Sealer:
1. Floors
and Slabs to Receive Sealer:
As specified in Division 9, Finishes.
2. Seal Floors
and Slabs at CONTRACTOR's Option:
a. All Floor Slabs
Except for the Following:
1) Those indicated on
the Drawings to receive seamless Floor surfacing.
2) Any slabs which
receive concrete or grout surfacing, in lieu of water or curing
compound.
3. Apply Sealant:
a. Apply sealant at
coverage rate not to exceed 500 square feet per gallon. b. Apply
as soon as slab or floor will bear weight.
c. Sealer:
1) Before applying
sealer, sweep entire surface clean with very soft bristled brush
which will not mark finish.
2) Apply sealer with
large, clean, mop type applicator.
3) Paint rollers are
not acceptable.
4) Workmen shall wear
flat soled shoes which will not mark or scar surface.
5) Do not allow
traffic on floors and slabs until sealer has dried and
hardened.
3.3
FIELD
QUALITY CONTROL A. Testing of Concrete:
1. During progress of
construction, the CONTRACTOR will have tests made to determine
whether the concrete, as being produced, complies with requirements
specified.
2. Tests will be
performed in accordance with ASTM C 31, ASTM C 39, and
ASTM C 172.
3. The CONTRACTOR will
make and deliver test cylinders to the laboratory and testing
expense will be borne by the CONTRACTOR.
4. Required Number
Cylinders:
a. Not less than 3
cylinder specimens, 6 inch diameter by 12 inch long, will be tested
for each 150 cubic yards of each class of concrete with minimum of
3 three specimens for
each class of concrete placed and not less than
3 specimens for each
half day's placement.
b. One cylinder will
be broken at 7 days and 2 at 28 days.
5. The CONTRACTOR
shall:
a. Test slump of
concrete using slump cone in accordance with requirements of
ASTM C 143.
b. Furnish test
equipment.
c. Do not use concrete
that does not meet specification requirements in regards to slump,
but remove such concrete from project site.
d. Test slump at the
beginning of each placement, as often as necessary to keep slump
within the specified range, and when requested to do so by the
ENGINEER.
e. Make provisions for
and furnish concrete for test specimens, and prepare test specimens
under supervision of the ENGINEER.
B. Assume
responsibility for care of and providing of curing
conditions for test specimens in accordance with ASTM C 31.
C. Air Entraining
Admixture:
1. Test percent of
entrained air in concrete at beginning of each placement, as often
as necessary to keep entrained air within specified range, and when
requested to do so by the ENGINEER.
2. Provide test
equipment.
3. Do not use concrete
that does not meet Specification requirements as to air entrainment
and shall remove such concrete from project site.
4. Test air
entrainment in concrete in accordance with ASTM C 173.
5. The ENGINEER may
at any time test percent of entrained air in concrete
received on project site.
D. Enforcement of
Strength Requirement:
1. Concrete is
expected to reach higher compressive strength than that which is
indicated in Table A as specified compressive strength f'c.
2. Strength
Level of Concrete:
Will be considered acceptable if following conditions are satisfied.
a. Averages of all
sets of 3 consecutive strength test results is greater or equal to
specified compressive strength f'c.
b. No individual
strength test (average of 2 cylinders) falls below specified
compressive strength f'c by more than 500 pounds per square inch.
c. Whenever one, or
both, of 2 conditions stated above is not satisfied, provide
additional curing of affected portion followed by cores taken in
accordance with ASTM C 42 and ACI 318 and comply with following
requirements:
1) If additional
curing does not bring average of 3 cores taken in affected area to
at least specified compressive strength f'c, designate such concrete
in affected area as defective.
2) The ENGINEER may
require the CONTRACTOR to strengthen defective concrete by means of
additional concrete, additional reinforcing steel, or replacement of
defective concrete, all of the CONTRACTOR's expense.
3.4
ADJUSTING
A. Repair of Defective
Concrete:
1. Remove and replace
or repair defective work.
2. Correct defective
work as specified in this Article.
3. Do not patch,
repair, or cover defective work without inspection by the
ENGINEER.
4. Provide repairs
having strength equal to or greater than specified concrete for
areas involved.
a. Chip out and key
imperfections in the Work and make them ready for repair.
5. Dry Pack Method:
a. Dry
Pack Method:
Use for holes having depth nearly equal to or greater than least
surface dimension of hole, for cone-bolt, and narrow slots cut for
repair.
b. Smooth
Holes:
Clean and roughen by heavy sandblasting before repair.l
6. Mortar Method
of Replacement: Use for following:
a. Holes too wide to
dry pack and too shallow for concrete replacement.
b. Comparatively
shallow depressions, large or small, which extend no deeper than
reinforcement nearest surface.
7. Concrete
Replacement:
a. Use:
When holes extend entirely through concrete section or when holes
are more than 1 square foot in area and extend halfway or more
through the section.
b. Method
of Repair for Surfaces of Set Concrete to Be Repaired:
First coat with epoxy bonding agent.
8. Acceptable Method
of Concrete Repair:
a. Make no repair
until the ENGINEER has accepted method of preparing surfaces and
proposed method of repair.
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