Concrete Repair, Rehabilitation and Retrofitting Proceedings of the International Conference, ICCRRR-1, Cape Town, South Africa, 21-23 November 2005

Keynote papers

• Infrastructure asset preservation: Is it a façade
• Concrete repair according to the new European Standard EN 1504
• Concrete repair – a composite system: Philosophy, engineering and practice
• Design of concrete to meet durability requirements; Development towards a performance specification in South Africa
• Potential and limits of durability design
• Repairs by the thin bonded overlay technique: The RILEM TC 193-RLS and last findings about the debonding mechanism
• Bonded concrete overlays – bond strength issues
• Structural rehabilitations with Ultra-High Performance Fibre Reinforced Concretes (UHPFRC)
• Developments in rehabilitation and consolidation of historical concrete and masonry constructions
• Use of new concrete materials for durable structures

Theme 1: Concrete durability aspects Causes and mechanisms of deterioration

• Latest insights and advances in understanding the ASR
• Acid attack of self compacting concrete
• Reaction mechanisms and thermodynamic modelling of Thaumasite Sulfate Attack (TSA); experimental modelling
• Performance of concrete exposed to freezing and thawing in different saline environments
• Frost salt scaling modeling of cement paste

Innovative materials and influences of material composition

• Surface protection systems on concrete: Investigations on durability and efficiency
• Effect of rubber aggregate incorporation on the resistance of cement-based mortar to shrinkage cracking
• Pore fluid analysis of cement mortar exposed to a chloride environment
• Resistance of concrete sewer coatings to chemical and biogenic attacks
• Construction of ferrocement water storage tanks and their comparison with R.C.C. and fiberglass tanks
• Research of fresh concrete treatment against desorption by means of polymers
• Durability of polymer modified concrete in marine environment
• Calcium aluminate cements for repair applications
• Durability of concretes with ferrous dusts exposed to liquid chemically aggressive environments
• Flexural behaviours of reinforced concrete member strengthened tension zone with reactive powder composite material
• Use of accelerated tests for evaluating the effectiveness of fly ash and ternary cementitious systems to control alkali-silica reactivity in concrete
• Mechanochemical synthesis of mullite and mullite-silicon carbide from secondary mineral resources used as an aggregate for fireproof concretes
• Prognostic models for creating new composite fireproof concretes and masses from secondary mineral resources
• Conception for creating superfireproof composite concretes and masses from secondary mineral resources
• Reduced carbonation of concrete by paraffin-wax
• Outdoor exposure of polymer-impregnated concrete (PIC) permanent form in Saudi Arabia
• Sustainability of polymer-impregnated concrete panel as permanent form
• Steel fibre reinforced SCC – a durable and robust construction material
• Research of aerated self compacting concrete problems
• Carbon fibre composites for a new generation of tendons
• Use of stainless steel for durable concrete structures
• Corrosion protection of reinforcement for concrete structures
• Synergic effect against corrosion between galvanized steel rebars and hydrophobic concrete
• Corrosion of RC columns repaired and wrapped with CFRP sheets
• Selected aspects of interaction of laser radiation with concrete surfaces

Service life modelling and prediction of durability

• Practical implementation of a reliability-based concrete durability design
• A numerical model for durability predictions
• Service life prediction, re-evaluation and optimum repair strategy
• Maintenance strategy versus simplified deem-to-satisfy rules
• Software for probability-based durability analysis of concrete structures
• Models for environmental actions for reinforced concrete structures in marine and road environments
• Modeling of temperature behavior of concrete during hydration
• Design of concrete structures for durable fire resistance
• Predicting chloride content profile in concrete using a concrete mix design parameter
• Modelling moisture and salt penetration in concrete
• Effect of duration and conditions of exposure on chloride diffusion
• Durability indexes and their use in corrosion rate prediction, with influence of binder type

Theme 2: Condition assessment of concrete structures Corrosion assessment and service life aspects

• Structural assessment methodology for residual life calculation of corroding concrete structures
• A rapid technique for detecting corrosion of steel in reinforced concrete
• Determination of corrosion related values for reinforced concrete structures
• Durability based design of RC structures in Persian Gulf region using DuraPGulf model
• Remaining service-life predictions: Experiences of Dutch investigations
• Influence of unsteady external environment on corrosion rate in reinforced concrete
• Assessment of reinforcement corrosion in a concrete highway tunnel
• Deterioration rate of concrete bridges in South Africa
• NDE/NDT and measurement techniques
• RILEM TC 189-NEC (Non-destructive evaluation of the concrete cover): Objective and status quo
• Non-destructive techniques for the condition assessment of railway bridges
• Monitoring the moisture distribution in concrete structures
• Nondestructive evaluation of concrete cover layer adequacy for corrosion protection
• Application of X-ray tomography for the verification of damage mechanisms in concrete
• Study of the assessment of defects in tunnel using an infrared thermographic technique
• Impact-echo techniques for non-destructive inspection of concrete structures
• Sensitivity of a non-destructive vacuum test method to characterize concrete permeability
• Air permeability measurements for the assessment of the in situ permeability of cover concrete
• Applicability of single-chamber vacuum cell for the evaluation of the air-permeability of concrete walls
• Effect of aging related to the freeze/thaw and deicing salt resistance of concretes
• A novel method to measure moisture profiles in concrete structures
• In situ moisture state of coastal concrete bridges
• Non-destructive evaluation of fire affected RC structure
• Bearing test methods for determining the residual load carrying capacity of rigid concrete pavement constructions before rehabilitation
• Chloride and sulphate content in concrete with Laser-Induced Breakdown Spectroscopy (LIBS)
• Assessment of foundation slabs with US-echo in the re-use process
• Consultant activity leading to improved technical prescriptions (NDT)
• Sample size of rebound method for the determination of concrete strength
• Shearography – a novel non-destructive testing technique for concrete strength appraisal
• Galvanostatic pulse corrosion measurements on a recent thermal swimming pool containing seawater
• Monitoring cementitious materials during setting and hardening with an ultrasonic shear wave reflection method
• Digital image analysis of cracks in concrete of different grades

Materials and structural assessments

• Evaluation of repair systems – basic principles
• Finite element analysis of RC beams retrofitted with steel plates
• Material and structural assessment of fire damage to the concrete deck of a motorway bridge
• The problem of evaluation of a three storey RC building for restoration, strengthening and vertical extension
• Simplified equation for the dynamic rigidity of RC beams
• Structural evaluation and rehabilitation of concrete arches in the Progreso pier
• Effects of strength degradations on seismic performance of RC buildings
• Seismic performance and damage level of RC buildings in urban area close to epicenter
• Experiments on flexural strengthened RC beams by CFRP sheets
• Creep and temperature effects on RC lining support slabs in multi flue chimneys

Case studies and surveys

• Rehabilitation of a grain concrete silo constructed by slip form method
• Rehabilitation of five major bridges on the Garden Route in South Africa
• Rehabilitation of hydraulic structures in tropical climates: A case study
• Repair of piles in Port of Dar es Salaam
• Initial survey of concrete structures in Swedish harbours – a case study in the Port of Trelleborg
• Damage assessment of a RC bridge structure showing damages at the prestressing steel
• Damage assessment of a RC tunnel structure showing delaminations
• Condition assessment of concrete bridges in Sweden
• Condition assessment of a turbo-generator foundation concrete structure
• High rise concrete façade defects: Causes and remedies
• Structural diagnosis and repair of fire damaged industrial structure
• The bridges of Timisoara – struggling throughout the time
• Repair and widening of the Carlisle Bridge
• Type of effects and extent of corrosive attack on cooling towers, rehabilitation and their service life

Theme 3: Concrete repair, rehabilitation and retrofitting - Design procedures and specifications

• Manual REHABCON on concrete repair and rehabilitation
• Manual on rehabilitation of concrete structures: REHABILITAR Network XV.F from the Iberoamerican Program for Science and Technology (CYTED)
• Evaluation of best repair option through the repair index method, RIM
• A client’s perspective on the implementation of rehabilitation procedures and durability specifications for structures on national roads in South Africa
• Securing a maintenance-free service life for concrete-silos

Repair methods and techniques

• Integrated protection system for chloride deteriorated concrete structures
• Rehabilitation of spherical bridge bearings on Foreshore Freeways Bridges, Cape Town
• 10 years experience with repair of a coastal concrete bridge
• Microbial ureolytic calcium carbonate precipitation for remediation of concrete surfaces
• Primers for the reinforcement as a repair method of concrete in columns of buildings exposed at a tropical marine environment. Influence of adjacent zones
• Injection into cracks in concrete made with reactive aggregates
• Cathodic protection of the historic rail bridge over the Silvermine River
• Cathodic protection of reinforced concrete – a system with woven carbon mesh
• The use of penetrating corrosion inhibitors as a treatment for structures corroding due to chloride ingress
• Concrete repair strategies including surface-applied corrosion inhibitors
• Performance of an organic corrosion inhibitor in concrete affected by both chloride and carbonation-induced corrosion
• Significance of the concentration of chloride in the repair of concrete highway structures using surface applied corrosion inhibitors
• Repair of the Pungwe Bridge in Mozambique
• Repair and rehabilitation of a prestressed deck bridge (case study)
• Shotcrete for rehabilitation of fire affected building
• Rehabilitation of 50 bridges in and around Port Elizabeth on the N2
• Use of two-stage (pre-placed aggregate) concrete in construction and repair of concrete structures
• Repair of historical concrete structures and monuments

Repair materials and systems

• Investigations on durability behaviour of concrete repair systems exposed to outdoor weathering
• Rehabilitation of concrete pavements with geotextiles and steel meshes
• Effect of admixtures on the fresh and hardened properties of modern rendering systems
• Behavior of cement-based patch repair materials in plain and reinforced concrete members
• Ultrasound monitoring of setting and hardening of shotcrete including alkali-rich or alkali-free accelerators
• The effect of silica fume and polymer on properties of repair concrete in simulated conditions of the Persian Gulf
• Effectiveness of surface coatings on limiting the ingress of chlorides into the barrier wall of the Confederation Bridge
• Flexible polymer-cement repair materials and their applications
• Properties of polymer-modified mortars with hydrocalumite for intelligent repair materials
• Aqueous polymers for the construction industry
• Rapid polymer concrete repairs using available fillers
• Polymers in concrete for repair: Where have we been and where are we going?
• Development of repair materials based on calcium sulfo-aluminate cement
• Modification of mortars and concrete by polymer dispersions based on saccharides
• Repair mortar colour matching by colourimetric method
• Modification of epoxy repair materials with waste fillers
• Characterization of the durability and service life evaluation of repair mortars for concrete elements
• Development of genetically engineered biosealant for crack remediation

Bonded concrete overlays

• Roadmap for improvement of crack resistance of repair materials
• On the compatibility measure in the repair systems
• Rehabilitation strategies and material performance of SCC used for the repair of the Jarry/Querbes underpass in Montreal
• Two different techniques for the evaluation of concrete surface roughness
• Relationship between surface characteristics and superficial cohesion of concrete
• Effect of surface preparation techniques on the cohesion of superficial concrete: Comparison of jack-hammering and water jetting
• Innovative non-destructive assessment of adherence failure of the top layer in an industrial floor
• Effects of repeated loading on the shear connection between old and new concrete
• Development of test method for cracking tendency of repair materials
• Crack development in bonded concrete overlays subjected to differential shrinkage: A parameter study
• Efficient testing of fibers with the Baenziger Block
• Survey on Swedish practice for bonded overlays and patch repair
• Bridge renewal under traffic load
• Microstructure, chloride migration and corrosion near the transition zone between substrate and repair concrete

Structural repairs and strengthening

• Textile reinforced concrete with AR-glass-fibre-multifilament yarn – a new innovative compound material for concrete repair and rehabilitation
• Strengthening RC beams by external reinforcement
• Flexural strengthening of RC beams via external prestressing
• Liesbeek Parkway bridge widening
• Characterizing old reinforced-concrete structures for compliance with new standard requirements
• Bond behaviour of post-installed rebars under one-directional and reversed cyclic loading
• Partial versus full wrapping confinement systems for concrete columns
• Strengthening of concrete masts using multi-axial AR-glass structures
• Experiment on shear resistance of RC wall-frame structures strengthened with CF-grids
• Shear strength of retrofitted reinforced concrete sections
• Performance evaluation of retrofitted dry-stack block masonry structure
• A unique strengthening solution for the Agter Paarl Road Bridge
• Bond behaviour and design of post-installed rebar connections

Seismic retrofit and rehabilitation

• Seismic retrofit strategy for under-designed reinforced concrete frame systems and subassemblies using FRP composites
• Seismic assessment and repair of corrosion-damaged reinforced concrete structures in New Zealand
• Seismic rehabilitation: A case study
• Experimental tests on seismic retrofit of RC columns
• Seismic strengthening techniques for existing RC Structures
• Structural retrofitting of buildings affected by earthquake in India with intensity of 7.7 on Richter scale
• A performance assessment of a RC frame building using a record obtained at its foundation

Retrofitting techniques and FRP systems

• Alternative analytical modelling of retrofitted reinforced concrete members
• Textile structures for shear strengthening
• Some results from the experiments of flexural strengthened RC beams by CFRP sheets
• Shear-flexure interaction of RC elements strengthened with FRP sheets
• Mineral based bonding of CFRP to strengthen concrete structures
• End anchors’ effect on the behavior of CFRP strengthened beams – experimental investigation
• Interaction between FRP shear strengthening and transverse steel reinforcement in RC beams
• Debonding of externally bonded CFRP at low and high temperatures
• Behavior of square concrete columns strengthened with Carbon Fiber Reinforced Polymer (CFRP) strips
• An empirical approach for the determination of ultimate FRP strain in FRP-strengthened concrete beams
• A novel Carbon Fiber Reinforced Polymer (CFRP) system for post-strengthening
• The behaviour of RC beams retrofitted with CARDIFRC after thermal cycling

Theme 4: Performance monitoring and health assessment

• Seismic performance evaluation of prestressed bridges constructed by cantilever method using displacement based approach
• Condition assessment of bridges in South Africa: Challenges and opportunities
• The use of nanotechnology in concrete structures for durability and health monitoring
• Non-destructive assessment of repair efficiency with impact-echo and ultrasonic methods – an overview
• Wireless monitoring of concrete structures using Micro-Electro-Mechanical Sensors (MEMS)
• Non destructive bridge supervision – traffic and dynamic influences
• Damage and condition assessment of R.C. structures for rehabilitation by linear polarization (N.D.T.)
• Acoustic emission monitoring and numerical modeling of a FRP-strengthened concrete structure
• The influence of synergistic effects of cyclic freeze-thaw, deicing-salt attack and bending stress on behavior of reinforced concrete
• Embeddable reference sensors for corrosion monitoring in concrete structures
• Full scale load testing of 3 bridges in Mozambique for rehabilitation

Biography

Professor Mark G Alexander, Department of Civil Engineering, University of Cape Town, South Africa

Dr Hans-Dieter Beushausen, Department of Civil Engineering, University of Cape Town, South Africa

Dr Frank Dehn, MFPA Leipzig, Germany  

Dr Pilate Moyo, Department of Civil Engineering,University of Cape Town, South Africa