Construction Spec for Concrete Work 1
1.1 Applicable Requirements, Codes, Standard and Specifications
1.1.1 OWNER’s Requirements
SUNP1-CON-CVL-SPEC-001 Construction Specification for Concrete Work
1.1.2 Standard & Code
1.1.2.1 SNI “Standard Nasional Indonesia”
SNI 07-2052-2002 Baja Tulangan Beton
SNI 15-2049-2004 Portland Cement
1.1.2.2 ACI “American Concrete Institute”
ACI 117 Standard Tolerances for Concrete Construction and Materials
ACI 207.1 Mass Concrete
ACI 211.1 Recommended Practice for Selecting Proportions for Normal and Heavyweight and Mass Concrete
ACI 301 Specifications for Structural Concrete for Building
ACI 304 Recommended Practice for Measuring, Mixing, Transporting and Placing Concrete
ACI 305 Recommended Practice for Hot Weather Concrete
ACI 308 Standard Practice for Curing Concrete
ACI 315 Manual of Standard Practice for Detailing Reinforced Concrete Structure
ACI 318-14 Building Code Requirement for Structural Concrete and Commentary
ACI 347 Recommended Practice for Concrete Formwork
1.1.2.3 JIS “Japan Industrial Standard”
JIS G 3112:75 Steel Bar for Concrete Reinforcement
1.1.2.4 ASTM “American Society for Testing & Materials”
ASTM A36 Standard Specification for Carbon Structural Steel
ASTM A82 Standard Specification for Steel Wire, Plain, for Concrete Reinforcement
ASTM A185 Standard Specification for Steel Welded Wire Reinforcement, Plain, for Concrete Reinforcement
ASTM A615 Standard Specification for Deformed and Plain Billet-Steel Bars for Concrete Reinforcement
ASTM C31 Practice for Making and Curing Concrete Test Specimens in the Field
ASTM C33 Standard Specification for Concrete Aggregates
ASTM C39 Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens
ASTM C94 Standard Specification for Ready-Mixed Concrete
ASTM C109 Standard Test Method for Compressive Strength of Hydraulic Concrete Mortars (Using 2 in. or [50 mm] Cube Specimens)
ASTM C136 Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates
ASTM C138 Standard Test Method for Density (Unit Weight), Yield, and Air Content (Gravimetric) of Concrete
ASTM C143 Standard Test Method for Slump of Hydraulic-Cement Concrete
ASTM C150 Standard Specification for Portland Cement
ASTM C172 Standard Practice for Sampling Freshly Mixed Concrete
ASTM C173 Standard Test Method for Air Content of Freshly Mixed Concrete by the Volumetric Method
ASTM C231 Standard Test Method for Air Content for Freshly Mixed Concrete by the Pressure Method
ASTM C260 Standard Specification for Air-Entraining Admixtures for Concrete
ASTM C494 Standard Specification for Chemical Admixtures for Concrete
ASTM C618 Standard Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use as a Mineral Admixture in Concrete
ASTM C1602 Standard Specification for Mixing Water Used in the Production of Hydraulic Cement Concrete
1.1.2.5 AWS “American Welding Society”
AWS A5.1 Specification for Carbon Steel Electrodes for Shielded Metal Arc Welding
AWS D1.8/D1.8M Structural Welding Code – Seismic Supplement
AWS D12.1 Recommended Practices for Welding Reinforcing Steel, Metal Inserts and Connections in Reinforced Concrete Construction
1.1.2.6 EN “Eurocode”
EN 1992-2-1:2004 Design of concrete structures
2. MAJOR MATERIALS
2.1 Cement
The sulfat and chloride content in soil and water, based on soil investigation laboratorium test report, shall be compared with the level of damage of concrete and rebar due to chemical attack according to the exposure category and classes of ACI 318-14. Cement shall conform to SNI15-2049, 2004, ASTM C150 or equivalent and the type as follows:
- Type I (Normal Portland Cement) for superstructure, general foundation and PC Piles.
- Type V (Severe Sulphate Resistance) or Portland Pozzolant Cement (PPC) shall be used for exposure in severe condition.
- Cement shall be obtained from one or more sources approved by CONSULTANT/OWNER for establish concrete continuing work.
2.2 Reinforcing Steel Bar
Certified mill test report of reinforcing steel bar shall be submitted and approved by CONSULTANT and OWNER. All reinforcing steel bar shall be free from loose mill scale, loose rust, oil, grease, paint or any harmful matter that may decrease the bond between the steel and concrete.
2.2.1 Structural Type
Structural type shall use deformed bar. Deformed bar shall conform to SNI 07-2052-2002; BJTS 40 or JIS G3112 or ASTM A615. Minimum yield strength is 400 MPa for BJTS 40 and 420 MPa for ASTM A615.
Table 1 Dimensions of Deformed Bar
Reference: SNI 07-2052, 2002; BJTS 40
Symbol | Bar Dia (mm) | Weight
(kg/m) |
CrossSect
(cm2) |
Remarks |
D 10 | 10 | 0.62 ± 6 % | 0.785 | Length=12 m |
D 13 | 13 | 1.04 ± 6 % | 1.327 | Length=12 m |
D 16 | 16 | 1.58 ± 5 % | 2.011 | Length=12 m |
D 19 | 19 | 2.23 ± 5 % | 2.835 | Length=12 m |
D 22 | 22 | 2.98 ± 5 % | 3.801 | Length=12 m |
D 25 | 25 | 3.85 ± 5 % | 4.909 | Length=12 m |
D 29 | 29 | 5.18 ± 4 % | 6.605 | Length=12 m |
D 32 | 32 | 6.31 ± 4 % | 8.042 | Length=12 m |
2.2.2 Non-Structural Type
Non-structural type such as wall post, reinforcement for concrete block wall, etc. may use plain bar. Plain bar shall conform to SNI 07-2052-2002; BJTP 24 or equivalent. Minimum yield strength is 240 MPa.
Table 2 Dimensions of Plain Bar
Reference: SNI 07-2052, 2002; BJTP 24
Symbol | Bar Dia (mm) | Weight
(kg/m) |
CrossSect
(cm2) |
Remarks |
Ø 6 | 6 | 0.220 ± 7% | 0.283 | Length=12m |
Ø 8 | 8 | 0.393 ± 7% | 0.503 | Length=12m |
Ø10 | 10 | 0.617 ± 6% | 0.785 | Length=12m |
Ø12 | 12 | 0.888 ± 6% | 1.131 | Length=12m |
2.2.3 Steel Wire
Steel wire fabric reinforcement shall conform to ASTM A185, JIS G3551 or equivalent as follow on Table 3. Minimum yield strength is 485 MPa. Welded mesh reinforcement shall be supplied in flat sheets or rolls depend on CONSULTANT approval. Binding wire shall be of 1.5 mm diameter approved soft iron wire and conform to ASTM A82.
Table 3 Dimensions of Wire Fabric Reinforcement
Reference: ASTM A185
Reference No. | Main Wire | Cross Wire | Unit Weight
(kg/m2) |
||||
Dia
(mm) |
Spacing
(mm) |
Area
(cm2/m) |
Dia
(mm) |
Spacing
(mm) |
Area
(cm2/m) |
||
M 4 | 4 | 150 | 0.84 | 4 | 150 | 0.84 | 1.32 |
M 5 | 5 | 150 | 1.31 | 5 | 150 | 1.31 | 2.06 |
M 6 | 6 | 150 | 1.88 | 6 | 150 | 1.88 | 2.96 |
M 8 | 8 | 150 | 3.35 | 8 | 150 | 3.35 | 5.26 |
Figure 1. Reinforcing Arrangement
2.3 Admixture
- Admixtures to be used in concrete shall be subject to prior approval from CONSULTANT/OWNER and shall conform to the following standards or be an approved equal water-reducing, retarding and accelerating admixtures according with ASTM C494.
- Accelerating admixtures containing calcium chloride shall not be used for reinforced concrete.
- Admixtures shall be the same composition as the admixture used in establishing the required concrete proportions.
- In high temperature or in chemical resistance such as acid, special treatment of concrete mixed are required.
- Chemical admixture shall be tested by competent and independent testing institutes prior to be used. The test certificate shall contain the following data:
– Exactly defined range of application.
– Exact instruction for use.
– Physical and chemical composition.
– Positive and negative attendant effects.
– Standard of the allowable portion of the chemical admixture in % (by weight) of the cement weight.
– Instruction for batching and mixing.
2.4 Aggregates
- The aggregates for concrete shall conform to ASTM C33 or equivalent.
- Aggregates failing to meet requirements of ASTM C33, but which have been shown by special tests or actual service to produce concrete of adequate strength and durability, may be used if approved by CONSULTANT.
- Sieve analysis conforming to the requirements given in ASTM C136 shall be carried out periodically and the test results shall be immediately submitted to CONSULTANT for approval.
2.5 Water
- The mixing water for the concrete shall be potable water clean and free from injurious amounts of oils, acids, alkaline, and other deleterious materials, and conform to ASTM C1602/C1602M.
- Mixing water must not contain more than 1000 ppm of sulfates, 500 ppm of chlorides and 2000 ppm of silt and does not have a saline or brackish taste.
- Non-potable water may be used if mortar test cubes made with non-potable water result in 7 day and 28 day strengths equal to at least 90% of strength of similar specimens made with potable water.
- The strength comparison shall be made on identical mortar cubes, except for the mixing water, prepared and tested in accordance with ASTM C109.
2.6 Grouting Material
Grouting material specification shall be general grout non shrink with strength 600 kg/cm2 at 28 days. Grout material shall be as manufacturer’s standard and shall not contain oxidizing and gas producing agents, catalysts, inorganic accelerators and chlorides as ASTM C109.
Material grout catalogue and testing result shall be submitted to CONSULTANT.
3. STORAGE OF MATERIALS
Cement, aggregates and admixtures shall be stored in accordance with ACI 304R.
- Cement shall be stored in weather tight buildings, which will provide protection from moisture and contamination. Sacks of cement shall not be stacked in piles exceeding 14 layers, for storage period less than 60 days, 7 layers if more. When storing cement in sacks the floors shall be a minimum of 30 cm above ground level and shall be paved with concrete and cover with plastic sheet to prevent the absorption of water.
- Aggregate stock shall be arranged and used in a manner to avoid excessive segregation and to prevent contamination with other materials or with other sizes of aggregates.
- Sand shall be allowed to drain until it has uniform moisture content before it is used.
- Reinforcing steel, whether fabricated or not, shall not be placed directly on the ground. Care shall be taken to prevent reinforcing steel from being deformed during storage.
- Admixtures shall be stored as recommended by the manufacturer.
4. PROPORTIONING
4.1 Strength of Concrete
The minimum compressive strength of concrete shall be as follow.
Table 4 Classification of Concrete Grade
Compressive Strength
At 28 days (Cylinder specimen) |
Application |
fc’ = 13 MPa | – Leveling concrete |
fc’ = 28 MPa | – For all concrete structures and general foundation |
fc’ = 35 MPa | – For concrete with exposure categories S2 and S3 (ACI-318 Table 4.2.1)
– For Underground Perimeter Wall – For Column, |
fc’ = 50 MPa | – For prestress concrete pile |
All value shall be tested by a cylindrical compressive strength method. Mix proportion of concrete shall refer to Section 5.
4.2 Slump of Concrete
- Slump of concrete shall be in accordance with Table 5.
Table 5 Slump of Concrete (without admixture)
Reference: ACI 211.1 Table 6.3.1
Type of construction | Maximum (mm) | Minimum (mm) |
Reinforced footing | 75 (100)* | 25 |
Plain footing, caissons and substructure walls | 75 (100)* | 25 |
Beams and reinforced walls | 100 (125)* | 25 |
Columns | 100 (125)* | 25 |
Road pavement and slabs | 75 (100)* | 25 |
* The value in parentheses is for concrete to be placed by pumping methods.
- Maximum slump shown in Table 5 may be increased 25 mm for methods of consolidation other than vibration.
- Contractor has to ensure any slump test will be used have to consider to comply compressive strength of concrete and have to consider no segregation occur on fresh concrete.
4.3 Maximum Size of Coarse Aggregate
Unless otherwise specified or approved by CONSULTANT, the maximum nominal size of aggregate shall not exceed:
- One‑fifth of the narrowest dimension between sides of forms.
- One‑third of the depth of slabs.
- Three‑quarters of the minimum clear spacing between individual reinforcing bars.
- All general purpose coarse aggregate shall have a maximum size of 40 mm.
4.4 Selection of Proportions
- The proportion of ingredients shall be selected in accordance with the requirements given in ACI 211.1 and to produce proper place-ability, durability, strength, and other required properties.
- All proportions for concrete shall be approved by CONSULTANT.
- As a rule proportion of ingredients including water-cement ratio shall be determined by trial mixing (see Table 6).
Table 6 Water Cement Ratio
Reference: ACI 211.1 Table 6.3.4
No | Compressive Strength At 28 days (Cylinder specimen) | Maximum Water Cement Ratio, by weight |
1 | fc’ = 13 Mpa | 0.79 |
2 | fc’ = 28 MPa | 0.57 |
3 | fc’ = 35 MPa | 0.50* |
4 | fc’ = 50 MPa | 0.40 |
* The water/cement ratio shall not exceed 0.50 by weight for concrete used in marine structure or structure in environtment attack (based on ACI 211.1 Table 6.3.4(b) and ACI 318-14).
Figure 2. Concreting Work Process
Continued to Construction Spec for Concrete Work 2