final tech. specification

8/3/2019 Final Tech. Specification

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1. STEEL REINFORCEMENT

1.1 a. This section shall apply to round bars 19 mm or smaller in

diameter with strength of SR 235 to SR 295 and deformed bars

D41 or smaller in nominal diameter with strength of SD 295 to SD390. Fabrication and placement of reinforcement of types,

diameters and strength levels not covered by this section shall beas specified in the Special Provisions.

b. The bar types, diameters scope of applications, as well as the

number, shapes and dimensions of bars shall be as specified in theSpecial Provisions. All longitudinal bars shall be deformed bars.

c. The types and diameters of weld mesh and reinforcement gridshall be in accordance with the Special Provision.

d. Splicing of reinforcement shall be lap slices, gas pressure

welding splices or special splices and shall be in accordance withthe Special Provisions. Unless specified in the Special Provisions,

the Contractor shall determine the method of splicing subject to

approval by the Architect/Engineer. Deformed bars with adiameter D35 or larger shall as a rule have no lap splices.

e. Reinforcement bars shall site-assembled or preassembled andshall be placed in accordance with the Special Provisions. Unless

specified in the Special Provisions, the Contractor shall determine

the placement method subject to approval by the

Architect/Engineer.

f. The Contractor shall formulate a construction plan and shop

drawings based on the Special Provisions and submit them to theArchitect/Engineer for approval.

GENERAL

FABRICATION AND

PLACEMENT OF

REINFORCEMENT.

1.2 a. Reinforcing bars to be used shall conform to JIS G 3112 (SteelBars for Reinforced Concrete Structures)

b. Weld mesh and reinforcement grid shall conform to JIS G3551 (Weld Mesh and Reinforcement Grid).

REINFORCINGBARS AND WELD

MESH

1.3 a. Deleteriously bent or defective bars shall not be used.

b. Reinforcing bars in coils shall be used after passing through a

straightener. Bars shall not be damaged during the straightening

process.

FABRICATION OFREINFORCEMENT

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2. CONCRETE PLAIN AND REINFORCED

2.1

2.2

2.3

2.4

2.5

2.6

This specification shall apply to cast-in-place reinforce concrete work,

including reinforced work for such structure as steel-framed reinforcement

concrete structures, and unreinforced concrete work.

Concrete work shall conform to all requirements of building works with

Japanese Architectural Standard specification (JASS 5, 2004).

Concrete shall be composed of Portland cement, water fine and coarse

aggregate and any admixtures as and when specified.

The concrete mixtures will be designed by the engineer who will determine

the required quality of the concrete for the structures covered by these

specifications. The desired strengths of concrete for various parts of theproject have been shown on the drawing.

Cement shall conform to the Standard specifications, as provided here under;

All cement shall be ordinary Portland Cement confirming to the requirementsof JIS R 5210 (Portland Cement).

Aggregates for normal concrete shall conform standard specification to JASS5 Section 4, (Concrete Material).

The maximum size of course aggregate shall be 25 mm, 20 mm or 15mm.

Aggregates for reinforced concrete should comply with JISS 5, 2004. The maximum

size of course aggregate is given in following Table.

Table 2.1 Maximum size of Course Aggregate Classified by Member Group (mm)

Member Gravel

Crushed stone,

blast-furnace slag

coarse aggregate

Recycled

aggregate

Columns,

beans, floor

slabs, walls

20,25 20 20,25

Foundations 20,25,40 20,25,40 20,25

Normal-weight aggregate shall be in accordance with (1) through (3) below:

Gravel and sand shall possess the qualities specified in Tables 2.1 and 2.2.

However, gravel and sand with an oven-dry density of 2.4g/cm3 or larger and

a water absorption of 4.0% or less and sand with a chloride content between

0.04% and 0.1% may be used in accordance with the Special Provisions,provided that the concrete containing such aggregates is proven to possess

the specified qualities.

SCOPE

SPECIFICATIONS

COMPOSITION

PORTLAND

CEMENT

AGGREGATES

GRADING

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2.7

Table 2.2 Quality of Gravel and Sand

Type

Oven-dry

specific

density

(g/cm3)

Water

absorption

(%)

Clay

lumps

(%)

Volume

lost by

wash test

(%)

Organic

impurities

Chlorides

(NaCl)

equivalent

(%)

Gravel 2.5 3.0 0.2 1.0 - -

Sand 2.5 3.5 1.0 3.0

Lighter in

color than

standardsolution

or sample

color

0.04(1)

Note: (1) 0.02 (%) for the long-term planned service life class.

Table 2.3 Standard Grading of Gravel and SandPercentage passing each sieve, by mass (%)

Nominal Sievesize (mm)

50 40 30 25 20 15 10 5 2.5 1.2 0.6 0.3 0.15

Gravel(Max.

size,mm)

40mm 10095-100

- -35-70

-10-30

0-5 - - - - -

25mm - - 100

95-

10

0

- 30-

70

- 0-

10

0-5 - -- - -

20mm - - - 100

90-

100

- 20-

55

0-

10

0-5 - - - -

Sand- - - - - - 100 90-

100

80-

10

0

50-

90

25-

65

10-

35

2-

10(1)

Note: (1) When using com bin at io ns of crushed sand and slag sa nd, the

percentage passing a 0.15-mm sieve shall be 15%.(2) Crushed stone and crushed sand shall conform to JIS A 5005

(Crushed Stone and Crushed Sand for Concrete), and slag

aggregate shall conform to JIS A 5011 (Slag Aggregate forConcrete).

(3) Recycled aggregates shall conform to Table 4.2 and 4.3, and

shall contain not more than 1.0% in weight of the grains thatfloat in the liquid of the density of 1.95(g/cm3).

(4) When using combinations of different types of aggregates, each

aggregate shall meet the quality requirements before blending

specified in (1), (2) or (3) above, respectively. However, thechloride content and grading shall meet the requirements of

Tables 2.2 and 2.3 after blending.

d. When chemical or physical unsoundness of aggregate is suspected,

the use of it and method of use shall be subject to approval by the

Architect/Engineer.e. Aggregates for concrete portions requiring exceptionally high fire

resistance shall be in accordance with the Special Provisions.

f. Lightweight aggregates shall be in accordance with Section 16

Lightweight Concrete.

a. Specified mixture proportions of concrete shall be determined to provide

the required workability, strength, Youngs modulus, durability.

MIX

PROPORTION

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2.8

b. Specified mixture proportions shall as a rule is established on the basis oftrail mixtures. However, when JIS A 5308 conformed ready-mixed

concrete is to be employed, the trail mixing process may be omitted.

c. The age for strength control of concrete in structure shall be within 91days and as specified in the Special Provisions. Unless specified in the

Special Provisions, it shall be 28 days.

d. The curing method of control specimens for the strength of concrete in

structure shall be in accordance with the Special Provisions. Unless specified

in the Special Provisions, the method shall be water curing under fieldconditions or standard curing when the designated age for strength control is

28 days and seal curing under field conditions when the designated age is

older than 28 days.

a. Proportioning strength shall be expressed as the 28-days old compressive

strength of standard-cured specimens, and shall be in accordance with (1) or(2) below depending on the designated age for strength control of concrete in

structure.

(1) Where the age for strength control of concrete in structure is 28 days, the

proportioning strength shall be the larger of the values calculated by Eqs.

(5.1) and (5.2).

F = Fq + T + 1.73 (N/mm2) (5.1)

F = 0.85 (Fq + T) = 3 (N/mm2) (5.2)

(2) Where the age for strength control of concrete in structure is n days(28


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2.9

respectively:

(1) T shall be determined using Table 5.1 according to the type of

cement and anticipated mean air temperature range. Where cement

other than those indicated in Table 5.1 is employed, T shall be asspecified in the Special Provisions.

(2) Tn shall be determined using Table 5.2 according to the type ofcement and anticipated mean air temperature range. Where cement

other than those indicated in table 5.2 is employed, Tn shall be as

specified in the Special Provisions.

Table 5.1 Standard Values of Correction Value T for concrete Strength

Type of cementRange of anticipated mean air temperature, t,

during 28 days after concrete placement (C)

Normal Portland

Cement 16 8 t < 16 3 t < 8

Correction value T

for concrete strengthin terms of air

temperature

(N/mm2).

0 3 6

Table 5.2 Standard Values of Correction Value Tn for Concrete Strength

Type of cement

Age n

(days)

Range of anticipated mean air

temperature, t, during 28 days after

concrete placement

Normal Portland

cement

42 8 4 t < 8 2 t < 4

56 4 2 t < 4 -

91 2 - -

Correction value Tn for

concrete strength in terms ofair temperature (N/mm2)

0 3 6

c. The standard deviation of the strength of concrete employed, shall be

established based on records at the ready-mixed concrete plant. Where no

record is available, it shall be the larger of 2.5 N/mm2 and 0.1 Fq.

a. The workability of concrete shall be such that the concrete can be placed

densely in all corners of forms and around reinforcing bars with minimum

bleeding and segregation under the conditions of portions to be placed and

methods of deposition compaction to be employed.

b. The slump of concrete with a quality standard strength of 33 N/mm2 orhigher shall be 21 cm at the highest. It shall be 18 cm at the highest for

concrete with a quality standard strength of less than 33 N/mm2. However,

the slump of lightweight concrete, plasticized concrete, high fluidityconcrete, high strength concrete, mass concrete and concrete placed

underwater shall be in accordance with Sections 16, 17, 18, 19, 22 and 25,

respectively.

WORKABILITY

AND SLUMP

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2.10

2.11

2.12

2.13

a. The maximum water-cement ratio shall be as specified in Table 5.3. For

cements other than those indicated in Table 5.3, the maximum water-

cement ratio shall be as specified in the Special Provisions.

Table 5.3 Maximum water-cement Ratios

Type of cement Max. Water-cement ratio (%)Portland cement (1)

Type A Portland blast-furnace slag cement

Type A Portland fly-ash cement

Type A Portland pozzolan cement

65

Type B Portland blast-furnace slag cement

Type B Portland fly-ash cement

Type B Portland pozzolan cement

60

b. The water-cement ratio shall be a value necessary for attaining the

proportioning strength but not more than the maximum value specified

in a above.

a. The cement content shall be not less than the values calculated fromthe water-cement ratio in 5.4 and unit water content in 5.5.

b. The cement content shall be at least 270 kg/m3.

The air content of concrete containing an air-entraining admixture, air-

entraining and water-reducing admixture or air-entraining and high-rangewater-reducing admixture shall be as specified in the Special Provisions.

Unless specified in the Special Provisions, it shall be 4.5%.

a. In placing, concrete shall be deposited as near as practicable to its

final position. Care shall be exercised to prevent concrete from stainingsurfaces of reinforcement, formwork and preset tile that are out of the

concreting section being placed.

b. At construction joints, concrete shall be placed and compacted withcare to leave no unsound portion near the joints due to inadequate

compaction or concentration of bleeding water.

c. Concrete shall be placed continuously to achieve monolithic concrete

in a section for which one sequence of concrete placing is planned.

d. The rate of placing shall be in the range of allowing efficient

compaction depending on the workability of concrete and construction

conditions of the relevant portions.

e. The free-fall height in placing concrete shall be limited to a range in

WATER-CEMENT

RATIO

CEMENTCONTENT

AIR CONTENT

PLACING

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2.14

2.15

2.16

which no segregation of concrete occurs.

f. The time limit for intervals between placing operations shall bedetermined in the range of causing no cold joints, subject to approval by

the Architect/Engineer.

g. Displacement of steel bars, forms. Spacers or steel bar supports shallbe corrected before placing concrete to ensure proper cover depth.

a. Concrete shall be compacted around reinforcement and embedded metals

and into corners of the forms so that dense concrete can be obtained.

b. Internal vibrators, form vibrators or tamping rods shall be used for

compaction. Other tools shall be used as auxiliary equipment where

necessary.

c. Internal vibrators shall be used on each fresh layer of concrete and

inserted vertically to a depth so that the tips of vibrators penetrate the top

level of the previously placed layer of concrete. The distance betweeninsertions of vibrators shall be not more than 60 cm, and vibrating shall be

continued until cement paste rises to the concrete surface.

d. Form vibrators shall be vibrated systematically according to the depth and

rate of concrete placing so that dense concrete can be achieved.

Beginning immediately after placement, concrete shall be protected from

rapid drying excessively hot or cold temperatures, rapid temperature changes,

vibration and external forces for the period necessary for sufficient hydration

of the cement and hardening of he concrete.

Concrete after placement shall be moist-cured by being covered withsheathing with low water permeability, curing mats or watertight sheeting, or

by water spraying, fogging, or application of a curing compound. The curing

period shall be in accordance with Table 8.1 according to planned service lifeclasses.

Table 8.1 Moist Curing Period

Planned service life classCement type

General/Standard Long-term

High-early-strength Portland cement 3 days 5 days

Normal Portland cement 5 days 7 days

Other cements 7 days 10 days

For concrete members 18 cm or more in thickness made using high-early

strength Portland cement or normal Portland cement, moist curing may beterminated even before the completion of the moist curing period specified in

a above, if it is confirmed that the compressive strength of the concrete*

meets the requirements of Table 8.2.

COMPACTION

CURING

MOIST CURING

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[Note] * This should be carried out in accordance with JASS 5 T-603(Method of Test for Compressive Strength for Estimating Strength of

Concrete in Structure). The curing method should be the same as that for

control specimens for concrete in structure.

Table 8.2 Compressive Strength of Concrete Required for Terminating Moist Curing(N/mm

2)

Planned service life classCement type

General/Standard Long-term

High-early-strength Portland cement

Normal Portland cement 10 15

a. When sheathing is to be removed after the period of retaining

sheathing specified in 12.9 but before the period specified in a above or

before the concrete attains the compressive strength specified in babove, the exposed surfaces of concrete shall be kept moist by spraying

water, fogging or other appropriate methods until the end of the specified

period or until the specified compressive strength is attained.

b. Under high air temperature, strong wind or direct sunlight, curing

shall be controlled to avoid rapid drying of the concrete surfaces.

a. The design cover depth shall not be less than the values given in

Table 10.1 and shall be specified in the Design Documents or Special

Provisions. Unless specified in the Special Provisions or DesignDocuments, the minimum cover depth shall be the values given in Table

10.1.

Table 10.1 Standard Values of Design Cover Depth

PortionDesign Cover Depth

With finishing(1) Without finishing

Portions not

in contact

with theground

Floor slabs, roof

slabs, nonbearing

walls

Indoor 30 30

Outdoor 30 40

Columns, beam,

bearing walls

Indoor 40 40

Outdoor 40 50

Retaining walls 50 50

Portion incontact with

the ground

Columns, beams, floor slabs,walls, risers of continuous

footing

50(2)

Foundations, retaining walls 70(2)

Note: (1) This refers to finishing effective in increasing durability.(2) For lightweight concrete, these values shall be increased by 10 mm.

b. Where effective measures against reinforcement corrosion are taken, thecover depth and corrosion-inhibiting treatment for diagonal bars placed at

corners and openings of buildings to control cracking shall be as specified

in the Special Provisions or Design documents. Unless specified in theSpecial Provisions or Design Documents, the design cover depth shall be

as specified in Table 10.1.

DESIGN COVERDEPTH

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3. STRUCTURAL STEEL (JASS 6 1993)

3.1 This Section covers general requirements for structural steel

work, fabrication, methods and precautions for erection ofsteel structures and other miscellaneous general requirements

to construction work in which structural steel is used for main

structural members of buildings or structure. This Section alsocovers furnishing, fabricating and installing and painting

metal not otherwise specified under other Sections of the

Specifications.

SCOPE

3.2. The applicable requirements of this Section shall apply to all

Structural Steel Work under this specification.

GENERAL

3.3. Structural steel shall conform to the requirement of

JAPANESE ARCHITECTURAL STANDARDS

SPECIFICATION (JASS 6 1993), Structural steelspecification for building constructions. The different shapes

of angles and their dimensions are provided in JASS 6 1993

Code, but for reference a typical detail provide in AnnexureA.

STRUCTURAL

STEEL

3.4 Except as otherwise shown on the Drawings, welding material

shall conform the standard specification for class of basemetal sizes and building conditions for standard shown in

table.

Standard No. Title

JIS Z 3211

JIS Z 3212JIS Z 3214JIS Z 3351

JIS Z 3352

JIS Z 3312

JIS Z 3315

JIS Z 3313

Covered electrodes for mild steel

Covered electrodes for high strength steelCovered electrodes for atmospheric corrosion resisting steelSubmerged are welding fluxes for carbon steel and low alloy

steelSubmerged are welding fluxes for carbon steel and high

strength steelMAG welding solid wires for mild steel and high strengthsteelSolid wire for CO2 gas shielded are welding of atmospheric

corrosion resisting steelAre welding flux cored wires for mild steel and high strengthsteel

WELDING

MATERIAL

3.4.1 Welding rod for manual welding of structural carbon steels,E-60 or E-70 series electrodes shall be used. For High-

strength low alloy steels E-70 series Low Hydrogen

Electrodes shall be used.

STRUCTURALWELDING ROD

3.5. Except as otherwise indicated on the Drawings or specified

herein, bolts and nuts shall conform the requirements of AIJStructure Steel Standard Specifications for Carbon Steel

Externally and Internally Threaded Standard Fasteners. Bolts

BOLTS, NUTS AND

WASHERS

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shall be Grade A for general application, with square orhexagon heads. Nuts shall be 4T of JIS B 1180 and 4T of JIS

B 1181 of similar material, finish class of fit and thread series

as their companion bolts and shall be washer-faced except asotherwise indicated or specified. Anchor bolts shall be of

diameter as shown hooked or eyed as required and provided

with sleeve nuts and double nuts as shown. Screw anchordevices for setting in concrete to permit withdrawal of anchor

bolts after concrete have set.

3.5.1 The Building Standards Law prescribes that hexagon boltfastening cannot be generally applied except for structures

with maximum eaves height of not more than 9m, span of not

more than 13m and total floor area of not more than 3,000m2.Therefore, hexagon bolt fastening is limited to relatively

insignificant structures.

HEXAGON BOLT

3.6 The angles, channels or girders being used shall conform to

the above mentioned specifications. All sections to beused in fabrication shall be of correct cut-lengths, not to produce any extra tension in the members due to

shortening or increase in cut-lengths, more than exactly

required.

FABRICATING

3.7 i) This part concerns anticorrosive paint on steel frames to

give them long-term rust resistance. The classification and

scope of paint shall comply with the special notes.

ii) Temporary anticorrosive paint to prevent stains due to rust

general during the construction period shall comply with thespecial notes.

ANTICORROSIVE

PAINT

3.8 The work covered by this Clause includes furnishing and

installing miscellaneous structural steel work includingthe following:

1. Steel stairs

2. Steel ladders

3. Fixed or removable railing

4. Embedded steel anchors/fasteners.

5. Miscellaneous work required in

structural steel.

MISCELLANEOUS

METAL

3.9 Structural steel trusses, stairs, door frames and windows etc

complete with stringers, grating treads and landings,structural steel supports, handrail supports and other

fastenings shall be furnished and installed in accordance

STEEL TRUSSES,

STAIRS, DOORFRAMES AND

WINDOWS ETC

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with the details, sizes and dimensions, and at the locationsshown on the Drawings.

3.9.1 All material for steel trusses, stairs, door frames and windowsetc, except as otherwise shown, shall be steel conforming

to JASS 6 (1993) Specifications for Structural Steel work

for building constructions.

MATERIAL

3.9.2 All Steel fabrications shall be in a first class workmanlike

manner. The units shall be shop assembled and fabricated

in sub-assemblies for convenient installation. Fieldconnections shall be made as indicated on the Drawings.

INSTALLATION

3.10 The embedded metalwork to be furnished and installed underthis Clause shall include anchor bolts, anchor bars, and

other metal work required for installation. The embedded

metal work shall be of materials and standards specifiedon the Drawings. Before placing concrete care shall be

taken to determine that all embedded items are firmly andsecurely fastened.

EMBEDDEDMETALWORK

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