international journal of pure and applied mathematics...

BEHAVIOUR AND IMPACT OF CONCRETE DECK SLAB, SHEAR CONNECTOR

AND STEEL BEAM IN COMPOSITE BRIDGE

A.Mohan1 and M.Tholkapiyan2

Department of civil engineering, Vel tech high tech Dr.Rangarajan

Dr.Sakunthalaengineering college, Chennai, India.

[email protected]

Abstract-The goal of the project was to develop a

bridge design that utilizes standard components to

assemble an adaptable bridge. In-service composite

steel girder bridges typically experience a variety of

deterioration mechanisms during their service lives,

ranging from cracking, spalls, and delimitations in the reinforced concrete deck to corrosion in the steel

girders. To date, several inspection techniques and

novel technologies have been widely implemented to

identify and measure different sources of defects

associated with bridge systems, especially within the

concrete deck. Despite successful implementation of

these evaluation methodologies, in this paper, the

impact of corrosion-induced subsurface deck

delimitation on the overall behavior and performance of

steel–concrete composite bridges is investigated using

finite element simulation and analysis. The accuracy

and validity of the modeling approaches were assessed

through a comparison to experimental data available in literature. A sensitivity study was performed to

investigate the influence of deck deterioration on the

system-level performance, load distribution behavior,

and failure characteristics of two representative

composite steel girder bridges.

Keywords: Deck slab, Shear connector, Steel Beam, Composite bridge.

1. Introduction

The composite bridge concepts cover the span range of

about 15 m to 50 m to link the traditional span lengths

of composite bridges – by that range they cover about 75 % of all span requirements for road bridges. Within

the scope of the project an extensive test program has

been performed including numerical simulations with

parameter and sensibility studies.

The test program has covered:

- Serviceability and fatigue tests with hybrid girders

- Push-out tests with dismountable shear connectors

and shear stud ∅ 25 mm

- Behavior of joints of partially- and fully prefabricated

slabs

- Fatigue tests on special joints of beams

- Plate buckling of stocky and slender webs

Furthermore software has been developed to verify

different kinds of constructions and enable a very fast

static calculation by the practical engineer.

Steel Concrete Composite (SCC) bridges are popularly

constructed throughout the World. Total shrinkage

strain in deck slab concrete of SCC bridges may be taken as 0.0003 (as per IRC-22, 1986). Reinforced

concrete slab on top of PSC girders, also come under

the purview of Composite construction.

(G.Radhakrishnan, 2009).But due to practical problems

composite construction using reinforced concrete slabs

on top of steel girders are more familiar now a day’s&

RDSO also insists Railways to go with reinforced

concrete slab on top of steel girders in ROB areas. Thus

using a reinforced concrete slab on top of steel girders

is an economical and popular form of construction for

highway & in Railway bridges. It can be used over a

wide range of span sizes.

A composite material (also called a composition material or shortened to composite) is a material made

from two or more constituent materials with

significantly different physical or chemical

properties that, when combined, produce a material

with characteristics different from the individual

components, ( IJARET, 2103). The individual

components remain separate and distinct within the finished structure. The new material may be preferred

for many reasons: common examples include materials

which are stronger, lighter, or less expensive when

compared to traditional materials.

Typical engineered composite materials include

• Composite building materials, such

as cements, concrete

• Reinforced plastics, such as fiber-reinforced

polymer

• Metal composites

• Ceramic composites (composite ceramic and

metal matrices)

Physical property

• The physical properties of composite materials are

generally not isotropic (independent of direction of

applied force) in nature, but rather are

International Journal of Pure and Applied MathematicsVolume 115 No. 7 2017, 247-255ISSN: 1311-8080 (printed version); ISSN: 1314-3395 (on-line version)url: http://www.ijpam.euSpecial Issue ijpam.eu

247

typically anisotropic (different depending on the

direction of the applied force or load). For instance,

the stiffness of a composite panel will often depend

upon the orientation of the applied forces and/or

moments. Panel stiffness is also dependent on the

design of the panel. For instance, the fiber

reinforcement and matrix used the method of panel

build, thermos set versus thermoplastic, type of

weave, and orientation of fiber axis to the primary

force. • In contrast, isotropic materials (for example,

aluminum or steel), in standard wrought forms,

typically have the same stiffness regardless of the

directional orientation of the applied forces and/or

moments.

• The relationship between forces/moments and

strains/curvatures for an isotropic material can be described with the following material

properties: Young's Modulus, the shear

Modulus and the Poisson's ratio, in relatively

simple mathematical relationships. For the

anisotropic material, it requires the mathematics of

a second order tensor and up to 21 material

property constants. For the special case of

orthogonal isotropy, there are three different

material property constants for each of Young's

Modulus, Shear Modulus and Poisson's ratio—a

total of 9 constants to describe the relationship

between forces/moments and strains/curvatures.

• Techniques that take advantage of the anisotropic properties of the materials include mortise and

tension joints (in natural composites such as wood)

and Pi Joints in synthetic composites.

1.1. Important terms

Composite Members

Structural members comprising prefabricated structural

units of steel, prestressed concrete, or reinforced

concrete and cast-in-situ concrete connected together in

such a manner that they act monolithically. (IJARET,

2103)

Shear Connectors

Structural elements, such as anchors, studs, channels

and spirals, intended to transmit the horizontal shear

between the prefabricated member and the cast-G-situ

concrete and also to prevent vertical preparation at the

inter-face.

Composite Action

For the purpose of design, if the prefabricated unit is

adequately supported before placing of the in-situ

concrete, it shall be designed to sustain self-load only. If the load of the formwork, constructional live load

and the in-situ concrete is carried directly by the

prefabricated unit without adequate props, this

additional load shall also be accounted for in addition

to self-load. The composite section shall be designed

for all the loads imposed on the member taking note of

the fact that the composite action of the member is

effective only for the loads imposed after the composite

action has started to function. ( Vikash Khatri, Pramod

Kumar Singh, 2012)

Figure 1. Principles of composite construction

Equivalent Section

For prefabricated units in prestressed concrete or

reinforced concrete, consideration shall be given to the

different module of elasticity of the concrete of the

precast and of the in-situ portions.( Vikash Khatri,

Pramod Kumar Singh, 2012)

For prefabricated units in steel, the effective gross area

of concrete slab shall be converted into the

corresponding equivalent area of steel. This shall be

done by dividing the effective area of the concrete slab

by the modular ratio.

Modulus of Elasticity

The values of module of elasticity of steel and concrete

shall be taken in accordance with requirements of the

relevant Indian Standard codes. The modular ratio shall

be also calculated on the. Basis of these modules of

elasticity except where otherwise laid down in the

relevant design codes.

Castellation’s

Protrusions or recesses on the top surface of the

prefabricated concrete units to provide the necessary

monolithic action between the cast-in-situ concrete and

prefabricated units.

1.2. Beam and slab construction (Composite

Bridges)

International Journal of Pure and Applied Mathematics Special Issue

248

The form of construction considered in this publication

is the beam and slab type, where a reinforced concrete

deck slab sits on top of several I-section steel girders,

side-by-side, and acts compositely with them in

bending. It is one of the most common types of recent

highway bridge in construction .A typical cross section,

for a composite bridge two-lane road with footways, is

shown in Figure 1.

Figure 2. Typical cross section of a composite bridge

two-lane road with footways

Composite action is generated by shear connectors

welded on the top flanges of the steel girders. The

concrete slab is cast around the connectors. This effectively creates a series of parallel T-beams, side by

side. The traffic runs on a non-structural wearing

course on top of the slab (there is a waterproofing

membrane between). The load of the traffic is

distributed by bending action of the reinforced concrete

deck slab, either transversely to the longitudinal beams

or, in some cases, by longitudinal bending to cross-

beams and thence transversely to a pair of longitudinal

main beams. The steel girders can be of rolled section,

for fairly short spans, or can be fabricated from plate.

Figure 3. Composite steel girder bridge at Vysarpadi

(Under construction)

Greater spans can be achieved if the bridge is lightly

loaded a farm access bridge or a foot bridge, for

example. In both the latter cases, where the beam is

shallow relative to the span, considerations of

deflection and/or oscillations may control the design.

Very little fabrication is necessary with Universal

Beams, usually only the fitting of stiffeners over

support bearings and the attachment of bracing.( Julio

F. Avalos & Karl E , project 66) Beams can be curved in elevation (camber) by specialist companies using

heavy rolling equipment. For highway bridges where

spans exceed the limits dictated by the maximum size

of Universal Beams, girders must be fabricated from

plates. Even for smaller spans, plate girders maybe

more suitable, because thicker webs and flanges can be

provided. Also, Universal Beams of 762mm serial size

and above can often be more economically replaced by

a similar plate girder. The use of plate girders gives

scope to vary the girder sections to suit the loads

carried at different positions along the bridge. A wide

variety of different forms in elevation and section has developed.

Figure 4. Composite steel girder bridge at Vysarpadi

(Under construction)

Figure 5. Composite Construction of Bridge no 1449A

–between Samayanllur & Sholavandan in Madurai

District

1.3. Advantages of Composite Steel Girder

Advantageous properties of both steel and concrete are effectively utilized in a composite structure. The

advantages can be fully utilized as summarized below:

1. Faster construction for maximum utilization of rolled

and/or fabricated components (structural steel

members) and hence quick return of the invested

capital.

2. Advantages based on life-cycle-cost analysis instead

of initial cost only.

3. Quality assurance of the steel material along with

availability of proper paint system suiting to different

corrosive environment.

4. Ability to cover large column free area in buildings

and longer span for bridges/flyovers. This leads to more

usable space.


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5. Reinforced cement concrete (RCC) slab is in

compression and steel joist is in tension. Hence, most

effective utilization of the materials can be achieved.

6. Better seismic resistance i.e. best suited to resist

repeated earthquake loadings, which require a high

amount of ductility and hysteretic energy of the

material/structural frame.

7. Composite sections have higher stiffness than the

corresponding steel sections (in a steel structure) and

thus bending stresses as well as deflection are lesser. 8. Keeping span and loading unaltered, a lower

structural steel section (having lesser depth and weight)

can be provided in composite construction, compared

to the section required for non-composite construction.

9. Reduced beam depth reduces the story height and

consequently the cost of cladding in a building and

lowers the cost of embankment in a flyover (due to lower height of embankment).

10. Reduced depth allows provision of lower cost for

fire proofing of beam’s exposed faces.

11. Cost of formwork is lower compared to RCC

construction.

12. Cost of handling and transportation is minimized

for using major part of the structure fabricated in the

workshop.

13.Easy structural repair/modification/maintenance.

14. Structural steel component has considerable scrap

value at the end of useful life.

15. Reductions in overall weight of structure and

thereby reduction in foundation costs. 16. More use of a material i.e. steel, which is durable,

fully recyclable on replacement and environment

friendly.

1.4. Some of the guidelines available for Composite

(Steel) Construction

I. These girders are welded type.

ii. End diaphragm girders should be provided along the

alignment of the bearing so that the entire span at one

end can be lifted with help of synchronous jacks for

attending bearings etc.

Cross bracing should be provided square to the girder

alignment. iii. All field joints of cross bracings and end

diaphragms are planned with High Strength Friction

Grip Bolts.

iv. Stud type/ flexible shear connectors are provided.

Rigid shear connectors of structural steel section

welded on top flange should not be provided.

v. Provision of Abutment/pier at railway boundary is

not mandatory. Standard span should be planned over

the railway track. Adjacent spans can also be of

required standard span.

1.2. Super Structure

1.2.1. Static System

This Design comprises single and continues composite

bridges with different levels of prefabrication for the

concrete slab. The concrete slab consists out of a solid

slab or a partially- as well as fully prefabricated deck

elements. For the main girders rolled and welded)

sections (including LP plate sections) can be used. The

amount of the main girders is depending on the

required road width or -class. Solid slabs need a

complete formwork before concreting the bridge deck.

By using fully prefabricated slabs the openings for the shear connectors in the elements (pockets or covered

channel) and the joints between the elements have to be

filled with mortar. By pre-stressing the fully

prefabricated elements before grouting the joints

between the elements can be closed up to a minimum.

Partially prefabricated elements are the formwork

during casting and shall also be used later as a part of the total slab height. The distance between the main

girders can be determined by varying the slab thickness

and the used slab technique (e.g. partially prefabricated

slab, slab = 10 + 20 = 30 cm

Max birder Distance ≈ 3.00 m). An appealing design of the

superstructure can be reached by a slenderness of about

L / h = 25

(L = span length, h = total construction height).

After completion of the slab all main girders are

connected in-between by the concrete slab. To

guarantee the stability of the main girders against

torsional-flexural buckling the girders shall be lateral

stiffened by using cross girders in the main axes of the piers and abutments only. These cross girders can be

designed in steel or in concrete. The bearings can be

placed under the cross girders or directly under the

webs of the main girder. Additional torsional stiffeners

can be applied to obtain a knuckle support in the

moment zero point. One main aspect of this design is

the erection of the bridge without cost-intensive temporary supports or propping’s. Furthermore the

casting sequences have to be considered for continues

bridges. The following Table 2-1 shows the

construction sequences for an in-situ casted solid slab

or a fully pre-fabricated slab (example for a two-span

bridge).( IJARET, 2103)

The steel girders are acting as simple beams during the first construction situation and are laterally supported

by the cross girders in the main axes. The dead load of

the steel girders is carried by these simple beams only

(System 1). After welding the hinge continues steel

beams are obtained which have to carry the partially- or

fully prefabricated deck elements as well as the solid

slab in the second construction situation (System 2). By

using fully prefabricated elements or a solid slab this

continues steel beams have to carry the dead load of the

solid slab or the fresh concrete and construction loads

only (System 2). By using partially prefabricated slabs

in the construction situation 3 a partial composite

action can be achieved by grouting the joints and pockets in the elements. The supplement fresh concrete


250

and the construction loads are carried after the setting

of the mortar by the partial composite cross section

(System 3). The partially prefabricated elements are

now acting as one shell (e.g. for wind loads). The static

utilization of the partial composite action provides a

very economic and optimized construction. The last

construction situation (System 4) is the continues and

finished composite cross section considering the

cracked concrete in the area of the hogging moment

(simplification). On this static system infrequent (e.g. finished permanent loads like caps and guard-rails) and

frequent (e.g. traffic) loads are applied under

considering the time dependent behavior of the cross

sections (creep- and shrinkage effects). The relevant

forces for each construction phase are multiplied by

safety- and combination factors and summed up. With

the load combinations and the estimated cross sections the following checks for the ultimate limit state and the

serviceability state are performed:

Ultimate limit state (ULS) of the steel girder (System 1

and 2):

- Ultimate resistance against positive bending

- Ultimate resistance against negative bending

- Ultimate resistance against positive / negative bending

taking interaction of shear in account

- Ultimate resistance against shear

- Ultimate resistance against torsional-flexural buckling

Ultimate limit state (ULS) of the composite beam

(System 3 and 4):

- Ultimate resistance against positive bending - Ultimate resistance against negative bending

- Ultimate resistance against shear

- Ultimate resistance against negative bending taking

interaction of shear in account

- Bonding strength of the shear connectors, number of

shear connectors

- Ultimate resistance against torsional-flexural buckling Serviceability limit state (SLS) of the composite beam

(System 3 and 4):

- stress analysis

- Crack width limitation and check of minimum

reinforcement

- Deflection check to complete the design of a

structure, the following items has to be carried out, but is not considered in the design guide:

- Distribution of the shear connectors

- shear resistance of the concrete chord

- Check of the contour area of the shear connector

- fatigue design

- Vibration behavior of the structure could be checked

potentially (especially for slender structures using HSS

and HSC

1.2.2. Steel construction

The main girders should be prefabricated and painted

with protection against corrosion in the workshop before arriving on site. By using welded plates for the

girders the required cross sections can be suited very

well to the stress distribution.(FHAW,2013).A cost

optimized steel construction can be reached by using

hybrid girders with lower strength steel for the web and

higher strength steel for the flanges. The number of

different cross sections of welded plate girder in

longitudinal direction should be minimized to obtain a

small number of joints and different plate thickness. In

the frame of the ECSC-Project hybrid girders have

been tested under fatigue loads. A further decrease of weight can be achieved by using LP-plates with a

variable thickness in longitudinal direction; these LP-

plates are rolled by a few mills only. The main girders

are connected on support or in span by using welded as

well as bolted connections and temporary cams. In the

area of welded connections the corrosion protection has

to be removed before the welding procedure and has to be completed after finishing the welding activities. The

usual steel grades for composite bridges are S235, S355

or S460. By using special steel, e.g. HISTAR from

Profile ARBED, a reduction of steel strength according

to the steel thickness can be precluded.

2. Behaviour Of Bridge Structures

2.1. An Overview

Steel-concrete composite bridges provide an efficient

and cost-effective form of bridge construction. By

utilizing the tensile strength of steel in the main girder

and the compressive strength of concrete in the slab,

the bending resistance of the combined materials is

greatly increased and larger spans are made possible.

River Bridges are steel/concrete composite deck slab bridges. Combining the advantages of steel and

concrete, they can be constructed to a low structural

height that could never be realized with steel bridges

and PC bridges. They are simple in structure, consisting

mainly of shape steel, and outperform other types of

bridges in terms of the on workability.

River Bridges can be constructed with effective spans

ranging from about 10 to 40 meters and skew angles of

45 degrees or more and can be adapted to changes in

structural height according to their longitudinal

alignment. They are now compatible with continuous

girders, expanding their range of applications...

2.2. Features

2.2.1. Low structural height

From among all structural types, River Bridges can

achieve the lowest structural height.

2.2.2. Rapid construction

The construction weight of River Bridges is far lighter

than that of concrete-based bridges, so heavy


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equipment can be downsized. In addition, formwork

and scaffolding are no longer necessary as the bottom

panels function as deck slab formwork, resulting in the

reduction of the construction work period.

2.2.3. Minimization of LCC

The RC deck slabs, which are of a highly durable structure, are almost maintenance-free and also

contribute to the minimization of life cycle costs.

2.2.4. Design ability

River Bridges can offer not only a slender appearance

thanks to their low structural height but also impressive

landscaping design.

2.3. Features Of The Structure

2.3.1. Low structural height

The core feature of River Bridge is their low structural

height. The effective span-structural height ratio is 1/30

to 1/42, and the height of girder ends can be reduced to a minimal 30 cm.

When the gap between the estimated high water level

and the planned road height in an urban area is

inadequate, as is often the case, River Bridges can offer

a sufficient geometric line road form. The extension of

the access road can also be shortened by reducing the

structural height so that it will be easier to secure the

necessary surrounding land.

Figure 6. Relationship between structural height and

connected road

2.3.2. Deck slabs with high durability

The results of moving wheel load driving tests prove

that the RC deck slabs of River Bridges are equal to

composite deck slabs in fatigue durability. River

Bridges can serve for 100 years thanks to the fatigue durability of these deck slabs and of the steel

members.( Vaghefi K, Ahlborn T, Harris D, 2014)

2.3.3. Weight of steel materials

The core feature of River Bridges is their low structural

height. The effective span-structural height ratio is 1/30

to 1/42, and the height of girder ends can be reduced to

up to about 30 cm.

2.3.4. DFT is used for the main girders

Shear connectors play the important role of letting the

steel panels and concrete behave together in a

composite structure. River Bridges (KCSB) use DFT as shear connectors for the main girders. DFT (Deformed

Flange T-shape) is the T-shaped steel produced by

cutting half H-shaped steel (Deformed Flange H-shape)

with projected lines, which are formed on the external

surface of the flange at the stage of rolling. The height

of the main girders can be adjusted via the height of the

extended web.

3. Details Of The Structure

Figure 7. Cross section of structure

3.1. New technology (Hyper Bridge)

Hyper Bridges are composite rigid-frame bridges made

up of a River Bridge with steel-concrete composite

structure bridge piers (REED method bridge piers)

rigidly connected there.

Figure 8. Hyper bridge

• Reduced construction work period: Since the

bridge piers (REED method bridge piers) and the joints

are prefabricated, construction work can be performed

rapidly.


252

• Lower structural height: The structural height

can be minimized by the superstructure design (River

Bridges).

• Improved earthquake resistance: The rigid-

frame structure gives Hyper Bridges higher earthquake resistance.

• Reduced maintenance costs: Maintenance costs

are reduced as the supports do not require maintenance.

• Better landscape: A superstructure with fewer

concave and convex portions presents a better

landscape.

Figure 9. Landscape Of Hyper Bridge

3.2. Basic Concept Of Composite Bridge Design

3.2.1. Applicable standard

The basic concept of design conforms to Specifications

for Highway Bridges Parts I to V (March 2002). The

“Design and Construction Work Guidelines for

Composite Deck Slab Bridges (draft): Composite Deck

Slab Bridge Research Center” applies to matters related to composite deck slab bridges.

3.2.2. Analysis method

In principle, design section force is calculated by

analyzing the grids formed by the main girders

consisting of bottom slabs for which the effective width

is taken into account, projected T-shaped steels (DFT)

and the extended webs. Simplified analysis can also be

applied to road bridges, such as right bridges or

pedestrian bridges.

3.2.3. Steel/Concrete composite structure

The pre-composition dead load is resisted by the cross

section of steel, and the post-composition dead load and

the live load are resisted by the composite cross

section. Compared with stud dowels, etc. for ordinary

composite girders, the steel/concrete composite

structure is inexpensive and lower in structural height,

as its integration depends on the adhesive force of

projections of DFT and concrete.

3.2.4. Two types of structure: solid type and hollow

type

The solid type is the standard structure for bridges with

an effective span of up to about 20 meters, whereas the

hollow type is for those with a longer span.

• Polystyrene foam is generally used for

embedded formwork.

• Hollow type bridges require coating on deck

slab reinforcing bars and the internal surface of the

hollow area.

Figure 10. Solid type bridge structure

Figure 11. Hollow type bridge structure

3.2.5. Shape of the steel girders

The standard shape of the steel girders is described

below.

• The DFT members are placed straight and

parallel to one another at equal intervals.

• The steel girders are level with one another in the

direction perpendicular to the center line of the

structure, and the cross fall of the road surface is leveled and adjusted with concrete.

3.2.6. Expansive concrete

To prevent cracking attributable to drying shrinkage,

expansive concrete is used.

3.3.7. Steel material requiring minimum

maintenance

For the purpose of saving labor required for future

maintenance, weather-resistant steel (bare type,

stabilizing-treated type, etc.) is used for the bottom and

side panels. Coating on plain steel is also available for


253

bridges in urban areas and bridges that need to be

colored. (Beaton JL, Stratfull RF, 1973)

4. Conclusion

The global analysis of the bridge structure was

performed using a space frame model. The foundations were represented by springs at the underside of pile-cap

level, with stiffness’s determined from the geotechnical

pile group analyses taking into account the ground

conditions. Dynamic response spectral analysis was

used to assess the effect of earthquake loading on the

bridge structure and foundations. The design spectra for

the three limit states (serviceability, ultimate, and

structural integrity) were applied to the dynamic

analysis model.

Each limit state analysis was performed in three

excitation directions, using the vertical spectra, and the

horizontal spectra for both the longitudinal and

transverse directions. This determined the interaction

between the frequencies of ground motion and the

natural frequencies of the structure. The total mass

included in the analysis was all permanent vertical

loads and one third of type HA traffic loading on one

lane in each direction. The CQC (Complete Quadratic

Combination) was used for combination of the effects

from different modes. While the CQC method is reasonable for single action

effects (one excitation direction only), it is difficult to

apply to multiple action effects arising from different

excitation directions that interact with each other. For

the combination of excitation directions a 100:40:40

combination rule was used, with 100% contribution the

primary direction and a 40% combination from the other two directions. Each direction was taken in turn

as the primary direction, and all results were enveloped

to determine the worst load effects.

In cases where liquefaction of the soil was assumed to

have occurred, the foundation spring stiffness’s were

modified based on updated results from the

geotechnical pile group analyses. The spectral analyses

were then re-run for these cases to ensure any changes

in modal response due to liquefaction were taken into

account.

References

1) (SSE/Bridges/MDU) Southern Railway Civil

Engg News Digest April l2012.

2) “Quality control in fabrication of composite

girders”,G.Radhakrishnan(SSE/Bridges/MDU)

Southern Railway Civil Engg News digest September

2012.

3) “Comparative study of prestressed steel-concrete

composite bridge of different span length and girder

spacing”, Vikash Khatri, Pramod Kumar Singh and P.

R. Maiti International Journal of Modern Engineering

Research Vol.2, Issue 5, Sept-Oct 2012.

4) “Influence of skew angle on continuous

composite girder bridge”, Gholamreza Nourish &

Zahed Ahmadi. American Society of Civil Engineers.

5) Research in Engineering & Technology

(IJARET), Volume 4, Issue 5, 2013,

6) Federal Highway Administration (FHWA). National bridge inventory database. Washington, D.C:

Federal Highway Administration; 2013.

7) Vaghefi K, Ahlborn T, Harris D, Brooks C.

Combined imaging technologies for concrete bridge

deck condition assessment. J Perform Constr Facil

2014:04014102.

8) Beaton JL, Stratfull RF. Environmental influence

on the corrosion of reinforcing steel in concrete bridge

substructures. Sacramento, CA: California Department

of Highways; 1973.

9) Bažant ZP. Physical model for steel corrosion in

concrete sea structures — theory and application. J

Struct Div 1979;105(6):1137–66.


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