704CONCRETE CONSTRUCTION

- 479 - SECTION 704 -- CONCRETE CONSTRUCTION

704.01Description

handling, placing, curing, and finishing of concrete for bridges, box culverts, arch culverts, headwalls, concrete seals, retaining walls and steps, foundations, substructures, and miscella neous structures. All work shall be done in accordance with theseS pecifications and the contract.

structures for extension or reconstruction.

704.02Material Requirements

the special provisions.

one class of concrete, the Contractor sh all advise the Engineer of the class of concrete to be used before the date of beginning of concrete construction on any project. No change shall be made in the class of concrete during the progress of the work without the written permission of the Engineer.

Table 704.01 Material Requirements Applicable Materials Section Anchor Bolts ..................................................... .1057, 1058 Curing Ma terials ................................................ .1010, 1011, 1012 Deformed Metal Center Joints and Metal Ke yway ................................................... . 1027 Dowel Ba rs ....................................................... .1022 Galvanized Ha rdware ....................................... .1059 Joint Sealing Filler ............................................. .1014 Paint and Pain t Materials .................................. .1077 Portland Cement Concrete ............................... .1002 Preformed Jo int Filler ........................................ .1015 Reinforcing Steel ............................................... .1020, 1023, 1024 Epoxy Coated Rein forcing Steel ....................... .1021 Structural Steel ................................................. . 708

704.03Construction Methods

the contract. All concrete rails on bridges and approach slabs shall be cast- in-place. Slip-forming will not be permitted for concrete rails on bridges and approach slabs.

concrete is placed.

spread footings to depths greater t han those shown in the contract, the Engineer will redesign the structure' s outline and reinforcement and provide the Contractor the appropriate revised plans.

Concrete Construction

- 480 - 3. Rock Anchors for Spread Footings:

with reinforcing bars of the size, lengt h, and number shown in the contract.

the bar diameters and shall be drilled to the depth indicated in the contract.

sand and shall be placed by a method which will insure that the hole is completely filled with grout.

the bars if the method that is used for placing the grout does not cause grout mix segregation.

encountered which render it impossibl e or impracticable to dewater the foundation bed in a satisfactory ma nner before and during the concrete placement, the Contractor shall be required to construct a concrete foundation seal course below the elevatio n of the footing of such dimensions as may be necessary.

requirements for concrete placed in still water as described in Paragraph 11. of this Subsection.

after completing the final placement, t he cofferdam shall be cleared of water. The seal shall be capable of excluding water from below so that the balance of the structure may be completed.

done in such a manner as to preclude the possibility of the movement of water through the fresh concrete.

24 hours thereafter, unless it is done fr om a suitable sump separated from the concrete work by a watertight wall or other effective means.

The falsework shall be designed and sealed by a Professional Engineer registered in Nebraska.

required by the contract, special provisions or for the following construction requirements:

spans greater than 50 feet (15 m) in length.

falsework is used.

beyond the exterior girder. .03

- 481 - c. Falsework design submittals shall meet the following criteria:

Department, in triplicate, and for information only. The supporting calculations or evidence of adequacy are also required by the Department.

Professional Engineer registered in Nebraska.

AASHTO's Standard Specifications for Highway Bridges and the Guide Design Specification for Bridge Temporary Works .

prior to erection of any falsework elements.

calculations will in no way constitute review and approval, and the Contractor shall be solely responsible for the falsework and its design.

loads without appreciable settlement or deformation. The Contractor shall construct all falsework according to the falsework plans submitted.

spaced, driven, and removed in a manner satisfactory to the Engineer.

the bridge's permanent substructure with the written approval of the Engineer. The Contractor shall repair any damage at no cost to the Department.

supported by mudsills if they are large enough to provide necessary support of the load.

complete.

complied with the conditions in Section 704.03 5.c.

elevations and grades indicated in the contract. The Contractor shall consider and compensate for deflections that the method of construction creates.

materials are subject to inspection by the Engineer to determine if they are suitable for their intended use. All materials which the Engineer determines to be damaged, defective, or otherwise unsuitable for use will be rejected.

impact and the effects of vibration by placement of barriers or limiting the access of construction equipment.

no longer needed.

Concrete Construction

- 482 - 6. Forms:

AASHTO Guide Design Specification for Bridge Temporary Works .

grades shown in the contract. They shall be substantial, unyielding, and constructed mortar tight. They shall be su fficiently rigid to prevent distortion due to pressures of concrete, vibrati on, and other loads incidental to the construction operations.

concrete shall not be used in the forms.

composition board, or other approved material. Only one type of liner shall be used throughout the structure. Liners shall be a uniform size and as large as practical. Joints shall be tight and smoothly cut.

Wood forms that are commercially manufactured to the specific shape of the 42 inch rail may be permitted. Forms shall be capable of producing a uniform surface, texture and appearance equal to that obtained by using steel panels in good condition.

panels or surfaces capable of producing a uniform surface, texture, and appearance at least equal to that obtained by using plywood form panels of good condition.

lined.

joints and grain give a continuous, uniform appearance.

3/4 inch (19 mm) at all exposed corners.

designated without the use of te mporary internal bracing.

or other approved material. No material which will adhere to or discolor the concrete shall be used.

designed to allow their removal to a de pth of at least 1/2 inch (13 mm) from the face without damaging the concrete.

mortar and the surface left sound, sm ooth, even, and uniform in color.

the concrete surface.

operation, it shall be terminated in a vertical bulkhead. .03

- 483 - e. Successive Pours:

and form work for the succeeding pours may be set on the curing concrete.

necessary to remove the wet burlap from the specific areas where the forming will take place. The exposed area shall be kept to an absolute minimum and shall be kept damp.

bridge rails shall not be placed until after the 10-day wet curing.

girders or beams shall be hung from adequate metal hangers.

measurable settlement of forms occurs when the concrete deck is placed.

hardware to the flanges of girders is prohibited.

slabs on steel or precast concrete “I” girders. Stay-in-place forms shall be used for interior areas only, where the forms are supported on both sides by girders. Stay-in-place forms must be adjustable to maintain proper slab thickness and shall be designed so no measurable settlement of forms occurs when the concrete deck is poured. Stay-in-place form support systems must be designed so as to maintain a minimum 1/2 inch (12 mm) clearance between the form support and the bridge deck reinforcing steel. Removable forms must be used outsi de of the exterior girders.

to prevent excess slab dead load.

place form design plans and computations to the Engineer prior to construction. These plans and computations are for information only. The Contractor is responsible for the per formance of the stay-in-place forms.

requirements of ASTM A 653/A 653M Coating Designation G615/Z500.

directly but shall be considered subsidiary to the item Class 47BD-_____ Concrete for Bridges.

approval of the Engineer.

sufficient strength to prevent damage to the concrete.

Concrete Construction

- 484 - (2) Forms not supporting the dead weight of the concrete shall remain in place for a minimum of 24 hours, exclusive of time which the air temperature is below 40 ˚F unless external heating is used.

12 hours, exclusive of time whic h the air temperature is below 40 ˚F unless external heating is used.

may be removed after 12 hours.

remain in place in accordance with the requirements for falsework.

until the concrete has reached 70% of the required compressive strength.

for a minimum of 5 days after the pour, with the following exceptions:

place for a minimum of 3 days.

inches shall remain in place a minimum of 24 hours.

falsework and supporting forms shall remain in place 10 days, exclusive of the time during which the temperature is below 40 ˚F unless external heating is used.

until the top slab has reached 70% the design compressive strength.

falsework for top slabs shall remain in place 7 days, exclusive of the time during which the temperature is below 40 ˚F unless external heating is used.

concrete to support its own weight uniformly.

of the span and progress toward the end supports.

with the requirements of Subsection 203.02, Paragraph 13.

Subsection 707.03.

and shall finish the bridge seats to the elevations shown in the contract. The top shall form a true cont inuous plane surface.

they may be placed and grouted in blocked out holes. .03

- 485 - c. Anchor bolts shall be set pl umb and at the proper location and elevation with templets.

or square and shall be 1 1/2 inches ( 38 mm) larger than the bolt diameter. An approved non-shrink grout shall be placed and vibrated or tamped to completely fill the well.

advance notice before starting to place co ncrete in each unit of the structure.

set before any concrete is placed.

soil until all pile driving within a radius of 25 feet (7.6 m) has been completed. If concrete pours must be made within this area before completion of pile driving, such concrete shall cure at least 3 days before further driving is allowed.

removed from the forms before concrete is placed.

substructure forms have been stripped and the concrete inspected for defects. The load of the superstructure shall not be allowed to bear on the substructure until its concrete has attained a compressive strength of 2,000 psi (14 MPa).

be used for conveying concrete to the forms.

occur.

equipped with baffle boards or shall be in short sections that reverse the direction of the concrete's movement.

rubber, or other nonreactive material.

coatings.

shall not be used for chutes

may damage the concrete or prevent proper construction.

when the descending ambient air temperature reaches 40°F (4°C) and shall

Concrete Construction

- 486 - not be resumed until an ascending ambient air temperature reaches 35°F (2°C).

concrete is being placed and the air temperature may be expected to drop below 35°F (2°C), the conc rete shall be protected.

operation.

concrete batches into fo rms shall be 30 minutes.

contract.

so that voids are not induced and the concrete is uniform and has smooth faces on all surfaces.

reinforcement shall be avoided.

length of the girder and brought up in horizontal layers.

pressures.

back from the face of the forms and to force the concrete under and around the reinforcement bars without displacing them.

exercised to avoid jarring the forms or placing any strain on the ends of projecting bars.

not be moved laterally more than 6 feet (1.8 m). Use of a vibrator to move concrete shall be prohibited.

(1.5 m). This includes free fall in a discharge pipe.

stream free of air pockets so that a constant pressure head is maintained.

as used in the remainder of the stru cture except cement content shall be increased 10%. c . T r e m i e :

diameter of not less than 10 inches (250 mm). It shall be constructed in sections having flexible, watertight couplings. .03

- 487 - (2) The tremies shall not be constructed of aluminum or aluminum alloy that will react with the concrete.

the discharge-end over the entire top surface of the work. They shall allow rapid lowering when necessary to retard or stop the concrete flow.

so as to prevent water fr om entering the tube and shall be entirely sealed at all times. The tremie tube shall be kept full at all times.

flow shall be induced by slightly raising the discharge-end and yet always keeping it in the concrete that is being deposited.

The surface of the concrete shall be k ept as nearly horizontal as practicable at all times.

mass free of voids. It shall not be disturbed after being deposited.

the forms shall be watertight.

the concrete inspected, and all laitance or other unsatisfactory material shall be removed from the surfaces.

stream and free of air pockets. The conc rete in the pipeline shall be ejected in such a manner that there will be no contamination or segregation of the concrete.

pressure head on concrete, and the free fall distance shall not exceed 5 feet (1.5 m) at discharge.

shall be performed at the final discharge point.

density. Consolidation shall be accomplished by mechanical vibration during and immediately after being placed as described in this Subsection.

not more than 18 inc hes (450 mm) thick.

preceding layer has taken an initial set.

Concrete Construction

- 488 - (2) The vibration frequenc y shall be greater than 4,000 impulses per minute.

concrete throughout a radi us of 18 inches (450 mm).

vibrators to properly consolidate each batch immediately after it is placed in the forms.

the speed of the vibrators.

the concrete around the reinforcement and embedded fixtures and into the corners and angles of the forms.

concrete slowly. Contact with reinforcement shall be avoided.

formation shall be avoided.

not farther apart than twic e the radius over which the vibration is visibly effective.

reinforcement to sections or layers of concrete which have hardened to the degree that the concrete ceases to be plastic under vibration.

mortar splashed on the reinforcement steel and the surfaces of forms shall be removed.

concrete.

concrete-steel bond at and near the su rface of the concrete while cleaning the reinforcement steel.

concrete shall be cleaned of laitance and other objectionable material to a sufficient depth to expose sound concrete.

the concrete adjacent to the forms shall be smoothed with a trowel.

joint, as in the sloped top surface of a wingwall, an insert shall be placed in the form to block out the wedge layer so that the placed concrete thickness is never less than 6 inches (150 mm). .03

- 489 - b. Limitations:

preceding pour is complete if the concrete compressive strength of the preceding pour has reached 2,000 psi (14 MPa).

substructure forms have been stripped and the concrete inspected for defects. The load of the superstructure shall not be allowed to bear on the substructure until its concrete has attained a compressive strength of 2,000 psi (14 MPa).

slab bridges until the falsework supporting the roadway slab has been released.

replaced, as directed by the Engi neer, at no additional cost to the Department.

concrete when the ambient tem perature is less than 40°F (5°C):

50°F (10°C) immediately after being placed.

enclose and protect the structure in su ch a way that the concrete and air surrounding it shall be maintained at a temperature between 50°F (10°C) and 100°F (38°C) for the first 72 hours after the concrete has been placed, and at a temperature between 40°F (5 °C) and 100°F (38°C) for the next 48 hours. The temperatur e of the air surrounding the concrete shall be gradually reduced to the outside air temp erature at a rate not faster than 5°F/h (2.8°C/h).

units is prohibited. A shield shall be provided on heating equipment involving combustion so that no exposed metal will be in contact with the source of heat.

concrete at the temperatures indica ted in Paragraph 14.a.(2) of this Subsection.

be adjusted to assure that the temperature of the concrete will not exceed 100°F (38°C) due to the heat of hydration.

control the temperature of the concrete below the maximum value specified. If loosening of the forms is necessary, prior approval of the Engineer must be obtained before the forms can be loosened.

Concrete Construction

- 490 - (5) When forms are to be removed after the specified 5 day period, the fall of the concrete temperature shall not be at a rate faster than 5°F (2.8°C) in any 1 hour.

thermocouple placed inside the fresh c oncrete to measure the concrete temperature. If a digital thermometer is not available, the Contractor shall provide four galvanized steel conduit tubes 1 inch (25 mm) in diameter and 12 inches (300 mm) long for each app lication of insulated forms. These tubes shall be provided with satisfactory rubber stoppers. The tubes shall be placed in the concrete as directed by the Engineer and shall be used to take the concrete's temperature. After curi ng is completed, the tubes shall be removed and the remaining holes shall be grouted.

thermometer with a thermocouple for the Department's use.

bridge deck concrete when the temperature will be less than 40 ⁰F during the 10-day wet curing period.

50⁰F immediately after being placed.

enclose and protect the structure in su ch a way that the concrete shall be maintained at a temperature between 50 ⁰F and 100 ⁰F for the first 72 hours after the concrete has been placed, and at a temperature of between 40 ⁰F and 100⁰F for the next 168 hours.

concrete temperature shall not be at a rate faster than 5 ⁰F/hour.

of concrete during cold weather, and permission given by the Engineer to place concrete during such time will in no way relieve the Contractor of the responsibility for satisfactory results. Any concrete showing damage from cold weather placement or curing shall be rejected.

shall be provided for all, except horizontal, joints.

surfaces. They shall be made only where located in the contract or indicated in the placing diagram unless otherwise provided in these Specifications and approved by the Engineer.

has hardened, the forms shall be retightened and the concrete surface shall be thoroughly cleaned of foreign matter and laitance.

to joint. The face edges of all joints shall be carefully finished true to line and elevation. .03

- 491 - e. Open Joints:

bearing seats shall be constructed acco rding to the details shown in the contract.

chipping or breaking the corners of the concrete.

material shall be placed in correct position as the concrete on one side of the joint is placed. When the form is removed, the concrete on the other side shall be placed.

joints shall be accurately shaped at the shop to conform to the sections of the concrete floor.

when placing the concrete.

decks, in accordance with the requirements of this Section.

surface finish.

irregular projections shall be removed from all surfaces.

honeycomb spots, broken corners or edges, and other defects shall be thoroughly cleaned, saturated with water, and then pointed and trued. The mortar shall be made from cement an d fine aggregate mixed in the same proportions as the concrete class being finished.

Subsection.

work shall be left carefully tooled and free of all mortar and concrete.

clean and true edges.

acceptable alternate to a rubbed finish. Concrete cast against steel forms or smooth, hard form liners, such as mas onite, metal, or fiberglass, may be given a "grout-cleaned" surface finish.

shall be float-finished.

Concrete Construction

- 492 - g. Rubbed Finish:

place at least 12 hours, exclusive of time when the temperature is below 40°F (5°C), before they are removed to allow a rubbed surface finish. Forms must remain in place as described in Section 704.03 paragraph 7 on all other formed surfaces of the structure.

rubbed surface finish, the concrete shall be kept wet while exposed.

and the wet-cure resumed until a 72-hour wet-cure period is complete.

water.

to set.

carborundum stone using a small quantity of mortar on its face. The mortar shall be composed of cement and fine sand mixed in the proportions used in the concrete being finished.

and irregularities have been removed, all voids are filled, and a uniform surface has been obtained.

carborundum stone and water. This rubbing shall be continued until the entire surface has a smooth te xture and uniform color.

dried, it shall be rubbed with burlap to remove loose powder and shall be left free from all unsound patches, paste, powder, and objectionable marks.

remove laitance and scale and to reveal partly obscured air bubble holes. Uneven form joints shall be ground smooth.

application of grout composed of 1 par t cement to 1.5 parts fine sand with sufficient water to produce a thick paint consistency.

be scoured with a cork float or other suitable material. This floating shall completely fill all holes and other irregularities in the surface.

from the holes, a float of sponge rubber or burlap shall be used to remove excess grout.

vigorously rubbed with dry burlap to completely remove any dried grout. No visible film of dry grout shall remain. .03

- 493 - (6) Grout cleaning shall be done when the air temperature is at least 40°F (5°C) and rising. All cleaning on an area shall be completed the same day it is started.

Portland cement added as necessary to produce the desired color.

wooden template. Sufficient excess concrete shall be maintained ahead of the strike-off so that coarse aggr egate is forced below the surface.

float to produce a reasonably smooth, fine-grained surface.

means of suitable edging tools.

rubbed finish shall be wet-cured or membrane-cured.

curing until the forms are removed.

are removed if they were in place for at least 72 hours.

shall be wet-cured.

exposed concrete be covered with a double thickness of wet burlap, which shall be kept saturated for at least 72 hours.

the exposed concrete shall be sprayed with a continuous, uniform coating of white pigmented, membrane-forming cu ring compound. The application shall be uniform and applied at a rate no less than 1 Gal/200 SF (0.2 L/m²).

joints, reinforcing steel, or surfaces which are to receive a rubbed finish. Any compounds applied to such surfaces or items shall be removed by blast cleaning.

throughout the 72-hour curing period. Any damage to the membrane during this period shall be immediately repaired.

benchmarks on structures. The benchmarks shall be installed near the right corner of abutment No. 1 on the horizontal portion of the top of the concrete barrier rail. The Contractor shall cast the benchmark into the concrete so its perimeter is flush with the finished surf ace and the top is above the surface. Recessed installations are not acceptable.

Concrete Construction

- 494 - b. The benchmark is a circular, 2 inch (50 mm) diameter, solid brass marker with a slightly domed head and a 2 inch (50 mm) long ribbed shank. The Contractor shall obtain th e benchmarks at the District Office. The Department will stamp the benchmar k with the required information.

concrete or masonry bridge or structure in the new bridge or structure, only those portions shall be removed which are so indicated in the contract. The connecting edges of the existing structure shall be cut, chipped, and trimmed to the required lines and grades without weakening or damaging that part of the structure to be retained. All ex isting reinforcing steel which is encountered shall be cleaned, straight ened, and extended into the new work as shown in the contract.

the removal operation shall be perfo rmed without damage to the girders or any portion of the structure to be retained.

to, the following:

damaging the existing reinforcing steel which projects from the top of the girder.

the top flange, damaging the flange to web weld or damaging the shear connectors that project from the top of the girder.

the Contractor shall submit to the Engineer details of the removal operations showing the methods, sequence of removal and equipment to be used.

demonstrate to the Engineer that the removal operation is acceptable by removing a 10 feet long x 4 feet wide (3 m x 1.2 m) section of the deck, over the top of a girder. If the gi rder or any other portion of the structure that is to remain in place has not been damaged, the Contractor may continue. If the Engineer determines that damage has bee n done or is likely to occur, the Contractor shall alter the removal operation.

that occurs during the trial demonstratio n shall be repaired as directed by the Engineer at no additional co st to the Department.

removal operation shall be repaired as directed by the Engineer at no additional cost to the Department.

Engineer renders it unfit to remain in place, it shall be replaced at no additional cost to the Department.

grade steel, as described in Section 709. .04

- 495 - 23. Barrier Curbs and Rails:

uniform appearance conforming to the horizontal and vertical lines shown in the contract or as directed by the Engineer, and shall be free of lumps, sags, or other irregularities.

vary more than 1/4 inch (6 mm) from the edge of a 10 foot (3 m) straightedge, and the front and back faces shall not vary more than 1/2 inch (13 mm) from the edge of a 10 foot (3 m) straightedge. Areas not conforming to the above requirements shall be removed and replaced by the Contractor at no additional cost to the Department.

faces of abutments, piers and MSE wa lls from staining caused by runoff from the weathering steel superstructu re. Acceptable methods of protection which may be used are:

abutments and the top ten fe et (three meters) of the piers and the MSE walls directly under the bridge shall be wrapped with 6 mil (0.15 mm) polyethylene to protect against staining. The polyethy lene wrap shall remain in place until after the bridge deck is poured. When the wrap is removed, concrete surfaces of abutments, piers and MSE wa lls shall be cleaned of any stains from the weathering steel.

place of the polyethylene wrap. The stai n resisting coating shall be applied to the exposed face of the abutments a nd the top ten feet (three meters) of the piers and the MSE walls directly un der the bridge. The stain resisting coating shall be applied to the concrete surfaces prior to erecting the steel superstructure.

the coating shall be in accordance with the manufacturer’s instructions. Minor appearance inconsistencies resu lting from application of stain resistant coatings hall be acceptable.

abutments, piers and MSE walls shall be cleaned of any stains from the weathering steel.

704.04Method of Measurement

computed by the Department in cubic yards (cubic meters) from dimensions shown in the contract. No field measurement is required. Pay quantities are those shown in the contract.

concrete quantity will be measured in cubic yards (cubic meters) of concrete placed within a volume bounded by vertical planes 18 inches (450 mm) outside and parallel to t he limits of the footings.

Concrete Construction

- 496 - 3. When seal course concrete is not shown in the bid proposal Schedule of Items, it shall be paid for as “extra work” when it is necessary to stop unforeseen water intrusion.

inch (645 mm2) or less in cross sectional area shall be neglected.

or cast-in-place concrete piles or pipe piles encased in the concrete.

displaced by steel reinforcement, H-pile, floor drains, or expansion joint material.

box culverts based on the cross-sectional area of the culvert's walls times the centerline length of the culvert.

constructed with either a horizontal or vertical break in barrel alignment.

be calculated by measuring the inside perimeter of the nominal box opening in feet (meters), then dropping the uni ts (feet) (meters) and multiplying the unit-less perimeter measurement times 0.05 cubic yards (0.125 cubic meters).

Square Yard (SY) [Square Meter (m 2)].

704.05Basis of Payment 1. P a y I t e m P a y U n i t

Class _____ Concrete for ________ Cubic Yards (CY) [ C u b i c M e t e r s ( m 3)] Seal Course Concrete Cubic Yards (CY) [ C u b i c M e t e r s ( m3)] Preparation of Bridge _____ Each (ea) Square Yard (SY) [Square Meter (m2)]

concrete and reinforcing steel pay items for the structure.

(225 mm), and any concrete placed in excess of 9 inches (225 mm) deep will be done at no additional cost to the Department. Seal course excavation is subsidiary to the seal course concrete.

Office and installing them shall not be measured for payment but shall be considered subsidiary to the items for which direct payment is provided.

construction. .05

- 497 - 6. Furnishing, placing, and grouting bars for rock anchors is subsidiary to the concrete bid item for the structure.

item for the structure.

average strength of all cylinders made on a specific day to determine the 28- day compressive strength of all of a group’s class of concrete poured that day. Concrete with a 28-day compre ssive strength not meeting the design compressive strength is subject to removal.

compressive strength, cores may be take n, at the discretion of the Engineer, within 45 days after the concrete was placed. The average of the cores will be used to determine the compressive strength.

strength is less than the design strength and the En gineer determines that the concrete is acceptable for use, the concrete is subject to a payment deduction. The pay deduction is shown below: 2 x (Design Compressive Strength - 28-day Compressive Strength) Design Compressive Strength = Percent Reduction Or 2 x (Design Compressive Strength - Av erage Core Compressive Strength) Design Compressive Strength = Percent Reduction

directly, but shall be subsidiary to the item “Class ____ Concrete for ____”.

- 498 - SECTION 705 -- PRECAST OR PRECAST/PRESTRESSED CONCRETE STRUCTURAL UNITS

705.01Description

the production of Precast or Prec ast/Prestressed Structural Units.

working drawings submitted in accordance with Subsection 105.02.

705.02Material Requirements

Table 705.01. Table 705.01 Material Requirements Applicable Material Section Concrete .......................................... .1002 Admixtures ....................................... .1007 Water 1005 Fine Aggregate ................................ .1033 Course Aggr egate ............................ .1033 Fly Ash 1008 Spiral Reinforcing Wire .................... .1023 Prestressed Steel Strand ................. .1026 Post-Tensioning Assembly Steel ..... .1025

Precast/Prestressed Structural Units shall be shown in the contract.

Concrete mix designs shall be proportioned in accordance with ACI Standard 318 and the following additional requirements:

for approval to the Engineer 4 weeks before beginning any concrete work. Refer to Table 705.03 for required testing for any mix design.

cement, aggregate, air-entraining admixture, and water. Concrete may also contain Class C or Class F fly ash, slag cement or Silica Fume and ASTM C 494 approved Type A, Type B, Type D, and Type F admixtures.

during the progress of the work without the prior written permission of the Engineer.

accordance with the requirements of Section 707.

authorized by the Engineer.

furnished with the approval of the Engineer. The yield and ultimate strength and other pertinent characteristics of this steel shall be submitted to the Engineer.