Engineering Commons^™

Evaluation Of The Chloride Ions Penetration Into Concrete Structure With The Surface Penetrants Served In Cold Marine Environment For 20 Years, Yanhua Kuang, Yuki Sakoi Associate Professor, Naoto Takashima Postgraduate, Minoru Aba Professor, Yoichi Tsukinaga Professor,

International Conference on Durability of Concrete Structures

The intrusion of chloride ions in concrete served in the marine environment is the leading cause of corrosion of steel bars. This paper examined the result of a long-term survey on the actual structure (the Tomakomai breakwater) treated with a set of penetrants partly. The survey was conducted twice, in the 12th and 20th years after construction.

The results showed that the penetrants could effectively reduce the penetration of chloride ions into concrete. After using the penetrants, the calculated surface chloride ion concentration was decreased by 5.04%/72.18% (the 12th year/the 20th year). As the service years increase, surface chloride ion …

Will Blended-Cement Systems With Similar Chloride Penetration Potentials Resist Similarly To Corrosion?, William Wilson, Vincent Labattaglia, Arezki Tagnit-Hamou, Luca Sorelli

International Conference on Durability of Concrete Structures

The capacity of concrete to prevent chloride ions penetration represents a key durability factor for steelreinforced structures exposed to de-icing salts and/or marine environments. Although blended-cement systems are commonly characterized with accelerated chloride penetration tests developed for Portlandcement concrete (e.g. the ASTM C1202 method), their microstructures and pore solutions are very different. This study aims to illustrate how the full potential of blended-cement systems to resist chloride ingress (and thus, chloride-induced corrosion) may not be justly disclosed by these accelerated tests using electrical current, even when tested after three months of curing. A Portland-cement-only mortar and five binary blended-cement mortars …

An Investigation On Moisture And Water Absorption In Cement Paste With Electrical Resistance Method, Manami Mizoguchi, Tatsuya Kitagawa, Totsawat Daungwilailuk, Yuko Ogawa, Kenji Kawai

International Conference on Durability of Concrete Structures

Moisture in concrete is one of main factors related to degradation and deterioration of concrete structure, and there are various moisture transport phenomena in concrete such as drying and absorbing. There are a lot of previous studies on the drying process of concrete to clarify the mechanisms of creep as well as shrinkage. However, few studies have been reported on the process of water absorption and moisture absorption although carbonation and chloride attack are strongly related to moisture and water absorbing. It is necessary to investigate moisture transfer in concrete in detail. This study investigated the moisture transfer in moisture …

Influence Of Pore Structure On Relative Chloride Diffusion Coefficient In Unsaturated Cementitious Materials, Yong Zhang, Guang Ye

International Conference on Durability of Concrete Structures

Chloride-induced corrosion of reinforcement in concrete structures is a serious issue in engineering practice. This paper investigates the influence of pore structure on the relative chloride diffusion coefficient Drc in unsaturated cementitious materials. The effects of various pore features, including porosity, pore size, and pore connectivity, on the continuity of water-filled pores in unsaturated porous systems are analyzed based on the Kelvin law and water desorption process. In the experimental program, different cementitious materials (OPC, slag, fly ash, and limestone powder) were used to prepare paste and mortar samples. The Drc of the mortar samples (one year old) at various …

Characterization Of Vibration Effects On The Internal Structure And Strength Of Regular And High Strength Recycled Concrete, Jovanca Smith, Rekha Rampit, R. Parey

International Conference on Durability of Concrete Structures

There is a need for more in depth understanding of the consolidation effect of concrete on its durability, especially in tropical climates. During placement of fresh concrete in molds vibration is required to prevent quality problems such as honeycombs and desegregation. Nevertheless, precise monitoring of concrete vibration time has been avoided by construction professionals. This results in concrete durability reduction of appropriately designed concrete due to variation in aggregate settlement, air void content and change in water to cement ratio. In this study, the effects of vibration time on concrete strength, aggregate segregation, and physical properties were experimentally investigated on …

Durability Of Cement-Based Materials In Drinking Water Storage, Matthias Schwotzer, Andreas Gerdes

International Conference on Durability of Concrete Structures

In order to provide a hygienic storage drinking water reservoirs have been coated with mineral mortar linings in all epochs of European history. However, modern cement-based materials often show in this special operational environment an inadequate durability. Even though drinking water is commonly not considered particularly harmful to cementitious systems, the chemical degradation of mortar linings in drinking water storage systems can occur very fast compared to other common deterioration reactions. This results in cost intensive repair measures and thus high life-cycle costs as well associated with an ecological burden. Furthermore, an insufficient understanding of degradation mechanisms and their underlying …

Effect Of External Loading On Durability Properties Of Pre-Stressed Concrete Girders With Microcracking, Savitha Sagari Srinivasan, Raissa Douglas Ferron, Michael Rung

International Conference on Durability of Concrete Structures

Over the last fourteen years, very early in the service life of pre-stressed concrete girders, unexplained microcracks have been observed. Their presence led to concerns about the future integrity of the girders, with one of the major concerns being corrosion of pre-stressing strands. As such, a comprehensive study aimed at understanding the effects these microcracks have on the service life of the girders was initiated. Eight in-service girders, under external loads, and five rejected girders, not under external loads, were selected for the study. In this paper, we present work on the temporal evolution of the cracks during a one-year …

Influence Of Surface Retarders On Texture Profile And Durability Of Upper Layer Of Exposed Aggregate Concrete Pavement, Mariusz Dąbrowski, Miachał Antoni Glinicki, Karolina Gibas, Aneta Antolik, Kinga Dziedzic

International Conference on Durability of Concrete Structures

Exposed aggregate concrete (EAC) pavement technology is used in Poland for construction of major highways and expressways. When properly executed, it is an efficient technique to provide desired friction for skid resistance without compromising the noise limitations. Concrete mix uniformity, proper dosing of retarding agent and optimal time to brush with a mechanical broom are supposed to have a major impact on the properties of the upper pavement layer. An experimental investigation was performed on exposed aggregate concrete specimens manufactured in the laboratory in a way to simulate the industrial production of two-layer concrete slab with exposed aggregate. The texture …

Freeze-Thaw Resistance Of Concrete: Insight From Microstructural Properties, Sam Adu-Amankwah, Leon Black Dr, M Zajac, J Skoceck, M Ben Haha

International Conference on Durability of Concrete Structures

Composite cements offer low carbon alternatives to conventional CEM I. These binders also generally tend to perform better than CEM I in aggressive chemical environments. However, their freeze-thaw resistance, evident through surface scaling and internal damage is usually impaired. Postulated theories on freeze-thaw induced damage do not fully explain the origin of this weakness in composite cement concretes.

This paper systematically presents the phase assemblage changes associated with the freeze-thaw of concrete specimen made from composite cements with and without limestone. The freeze-thaw test was performed on concrete according to CIF method based on CEN/TR 15177 and the corresponding cement …

Influence Of Exposure Environments On The Durability Of Slag-Blended Cements, Joseph Onah Ukpata, P. A. M. Basheer, Leon Black

International Conference on Durability of Concrete Structures

Both chlorides and sulphates combine in seawater to affect the durability of reinforced concrete structures located in marine environments. This paper presents the results of an experimental study on slag blended cement systems, cured for 7 days, before exposure to a combined solution of sodium chloride (30 g/L) and sodium sulphate (3 g/L). Two slags of different chemical compositions, designated as slags 1 and 2 were respectively blended with Portland cement CEM I 52.5R at 30 and 70 wt.% replacement levels. Mechanical tests on mortar samples were complemented by microstructural examination and chemical characterisation on paste samples, all using a …

Fib Model Code 2020 – Durability Design And Through Life Management Of New And Existing Structures, Frank Papworth, S Matthews

International Conference on Durability of Concrete Structures

Work has recently started in fib (Fédération Internationale du Béton) on the preparation of a new fib Model Code for Concrete Structures, under the working title of Model Code 2020 (MC2020). This will be a single code dealing with both new and existing concrete structures, that is both the design of new structures and all the activities associated with the assessment, interventions and the through-life management and care of existing concrete structures. Numerous goals relating to durability and service life design have been identified, including that ideally MC2020 should incorporate:

• Better models for deterioration processes addressing issues such as …

Absorption, Porosity, Capillarity And Chloride Diffusion In Ultra High Performance Concretes, José Manuel Gandia-Romero, José Enrique Ramón-Zamora, Isabel Gasch, Manuel Valcuende, Rafael Calabuig, Victor Calvet, Pedro Serna

International Conference on Durability of Concrete Structures

Concrete durability performance can be assessed by a number of parameters, among which permeability properties are key. In this experimental work, the permeability to water and the diffusion of chlorides in Ultra High Performance Concrete (UHPC) are studied. To this end, three types of concrete were made: two Ultra High Performance (one with fibers and one without fibers) and a Conventional Concrete (CC) of w/c ratio equal to 0.5. The compressive strength of Ultra High Performance Concretes was 130 MPa, and that of conventional concrete was 50 MPa. All of them were cured at a temperature of 20°C and RH …

Performance Of Concrete Made With A Calcined Clay – Limestone-Portland Cement Exposed To Natural Conditions, Fernando Martirena, Ernesto Díaz, Dayran Rocha, Hamed Maraghechi, Karen Louise Scrivener

International Conference on Durability of Concrete Structures

This work presents the results of an investigation carried out to assess durability of concrete made with a calcined clay- limestone-Portland cement with 47% of clinker, hereafter named LC3, produced during an industrial trial in 2013. LC3 was used to cast concrete blocks and later expose them at a natural location at the northern coast of Cuba. Reference concrete was cast with Cuban Portland cement having 88% of clinker. Throughout three years (2015, 2016, 2017) concrete cores were systematically taken and the specimens were subjected to a testing program that included Formation factor, chloride profiling, surface resistivity, air permeability and …

Enhancement Of Durability Characteristics Of Geopolymer Concrete With Manufactured Sand, Abdul Aleem, T Shanmuga Priya

International Conference on Durability of Concrete Structures

Geopolymer Concrete is the concrete made without using any quantity of cement. Instead the waste material from the thermal power station called fly ash is used as the binding material. This fly ash reacts with alkaline solution like sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) and forms a gel which binds the fine and coarse aggregates. Similarly another artificial material called manufactured sand (M-Sand) is also used as the fine aggregate against the normal river sand. The durability of Geopolymer Concrete with M-sand was studied by casting cubes of size 100 x 100 x 100 mm. The cube specimens were …

Impact Of Water Content On The Performance Of Alkali-Activated Slag Concretes, Susan A. Bernal, John L. Provis, Jannie S.J. Van Deventer

International Conference on Durability of Concrete Structures

In this study, we report the effect of varying the water/binder (w/b) ratio on the performance of sodium silicate activated concretes. Compressive strength development and water transport properties of these concretes were assessed, along with their resistance to carbonation. The results demonstrate that varying the water content within a reasonable range induced negligible changes in the compressive strengths of these concretes, when a constant paste content was used. A direct correlation between the w/b ratio and the amount of permeable voids in the concretes was not identified. The carbonation behaviour of these concretes changes prominently depending on the CO2 concentration …

Improving The Laboratory Design Of Asphalt Mixtures To Enhance Asphalt Pavement Durability, Ali Hekmatfar

Open Access Dissertations

Most departments of transportation, including Indiana’s, currently use the Superpave mixture design method to design asphalt mixtures. This method specifies that the optimum asphalt content for a given gradation be selected at 4 percent air voids. During construction, these mixtures are typically compacted to 7-8 percent air voids. If mixtures were designed to be more compactable in the field they could be compacted to the same density as the laboratory mixture design, which would increase pavement durability by decreasing the in-place air voids. The objective of this research was to enhance the asphalt mixture design method in order to increase …

Progress In Durability Study Of Frp Materials, Zeng-Zhu Zhu, Ying-Wu Zhou, Li-Li Sui, Feng Xing, Jia Du

International Conference on Durability of Concrete Structures

During the past decades, FRP strengthened RC structures have attracted worldwide interest in both application and research. Nowadays, as more and more infrastructures are being suffered from severe corrosions due to harsh and extreme environments, the durability of FRP strengthened RC structures has generally emerged as the most important issue in research. Thus, the paper presents the latest progress in durability study of the FRP materials through an in-depth review and analysis on existing extensive investigations. The time-dependent performances of two types of FRP materials of carbon FRP (CFRP) and glass FRP (GFRP) under severe environments of humidity, high temperature, …

Research On Concrete Durability Improving For Existing Island-Building And Its Application, Mao Jianghong, Zhu Yaofeng, Xu Fangyuan, Jin Weiliang, Xu Yidong, Chen Xu

International Conference on Durability of Concrete Structures

China’s coastal cities contain a large number of islands with abundant human activities, in which buildings are in a typical marine corrosion environment and the corrosion of reinforced concrete structures is very prominent. This paper makes research work on two aspects: (1) the durability assessment and durability improvement after a thorough investigation of the architecture of Xiangtan County, Ningbo city, on an island and (2) the application research of the bidirectional electromigration rehabilitation (BIEM) technology to enhance the durability of existing island building life. This paper designs a set of BIEM equipment based on solar power supply and develops a …

Study Of Water Permeability Of Lightweight Concrete, Xiaoxiao Xu, Haibin Yang, Hongzhi Cui, Zitao Lin, Tommy Yiu Lo

International Conference on Durability of Concrete Structures

The relationship between water permeability and different levels of the tested layers from the top surface to the bottom surface of the lightweight concrete specimens is determined in this study. It is beneficial to develop the design criteria for a durable lightweight concrete. The water permeability coefficient K of the samples was determined by water permeability test using GWT. It is found that the water permeability coefficient K of the three layers in each set of samples tends to decrease as the level of the tested from the top surface increase. Larger Rebound Number and higher density in the bottom …

Surface Treatment Of Cement-Based Materials With Nanosio2, Pengkun Hou, Xin Cheng, Jueshi Qian, Surendra P. Shah

International Conference on Durability of Concrete Structures

A dense surface structure of cement-based material is favorable for its resistance to the impacts of environment. In this work, effectiveness and mechanisms of the surface treatment of cement-based materials with nanoSiO₂ of different states, that is, colloidal nanoSiO₂ (CNS) and the in situ formed nanoSiO₂ gel through the hydrolysis of its precursor of tetraethoxysilane (TEOS), by brushing and soaking techniques, were investigated. Results showed that both CNS and TEOS are capable of reducing the liquid and gaseous transport properties of hardened cement-based materials, although at a different extent. It revealed that the pozzolanic reactivity and the …

Development Of Internally Cured Concrete For Increased Service Life, John Schlitter, Ryan Henkensiefken, Javier Castro, Kambiz Raoufi, Jason Weiss, Tommy Nantung

JTRP Technical Reports

Higher strength, lower water to cement ratio (w/c) concrete has been advocated over the last two decades due to its increased strength and reduced permeability. The lower w/c of these concretes makes them susceptible to autogenous shrinkage. This autogenous shrinkage can be significant and can be a contributing factor to early age cracking. Internal curing was investigated as a potential method to improve the durability of concrete pavements and bridge decks. Prewetted lightweight aggregate was used to supply water to the hydrating cement paste. This additional water can counteract the hindered strength development, suspended hydration, autogenous shrinkage, and early age …

Implementation Of A Non-Metallic Reinforced Bridge Deck, Volume 2: Thayer Road Bridge, Robert J. Frosch, Ali Cihan Pay

JTRP Technical Reports

The primary maintenance problem with bridges in Indiana has been deterioration of the concrete deck which is often related to corrosion of the reinforcing steel. While a corrosion protection system consisting of epoxy-coated reinforcement in combination with 2-1/2 in. of Class C concrete cover has been used in Indiana, research and experience have demonstrated that this system can be compromised. As an alternative solution to the corrosion problem in reinforced concrete, fiber reinforced polymer (FRP) bars which are corrosion resistant can be provided as reinforcement. This research was divided into two phases directed towards the implementation of a nonmetallic reinforced …

Interaction Between Micro-Cracking, Cracking, And Reduced Durability Of Concrete: Developing Methods For Considering Cumulative Damage In Life-Cycle Modeling, Zhifu Yang, W. Jason Weiss, J. Olek

JTRP Technical Reports

It is becoming increasingly popular to utilize numerical simulation models to predict the long-term performance of concrete pavements and structures. The majority of these models have been developed using laboratory test data that considers concrete in an uncracked state. While uncracked concrete exists as the best case scenario, frequent cracking occurs in real structures that could have a profound impact on life cycle performance. Cracks from several sources may accumulate and interact thereby accelerating the deterioration of concrete. For example, the distributed cracking caused by freeze/thaw damage can substantially increases the rate of water absorption and reduces the load carrying …

An Investigation On Transversely Prestressed Concrete Bridge Decks, J. A. Ramirez, Jhon Paul Smith

JTRP Technical Reports

This study is concerned with the development of design specifications for the use of transverse post-tensioning in concrete bridge decks. The ultimate goal behind this proposal is to improve the durability of concrete bridge superstructures. Experimental results from previous studies are used to validate the analytical models implemented in the development of the design specifications. It is found that the required distribution of transverse post-tensioning is such that different application levels of prestressing are required in regions containing the interior and exterior (or outermost) diaphragms. It is also concluded that the magnitude of such transverse forces is a function of …

Design Of Durable Concrete Railroad Crossings, Anthony J. Lamanna, Charles F. Scholer

JTRP Technical Reports

Existing precast concrete railroad crossings in the state of Indiana are experiencing too short a life expectancy. This study proposes methods that can be used to produce durable concrete railroad crossings with satisfactory rideability, durability, and longevity. Thirty-two precast concrete railroad crossings were visited in central and northern Indiana. Failures were determined to belong to three major categories: structural capacity causes, environmental causes, and material property causes. A concrete mix was evaluated at three different polyolefin fiber contents and without fibers. Beams were tested in flexure, and modulus of rupture and first crack deflection were recorded for each beam. Cylinders …

Performance-Related Specifications For Concrete Bridge Superstructures, Volume 1: Performance Parameters And Related Procedure For Concrete Bridge Superstructures, J. A. Ramirez, Jhon Paul Smith

JTRP Technical Reports

In Volume 1 of the final report, the identification of performance levels and parameters, and the development of acceptance criteria, have been addressed. Emphasis has been placed on the development of a methodology for a Performance Related Specification, PRS, for concrete bridge superstructures. The implementation of the methodology, presented in the form of a user-friendly computer program, is project specific. It requires the mean and standard deviation (or definition of a probability distribution) of the input parameters for the performance predictive models. This is done for both the as-designed condition and the as-built condition of the structure. The contractor is …

Performance-Related Specifications For Concrete Bridge Superstructures, Volume 4: Bond Of Epoxy-Coated Bars With Thicker Coatings, J. A. Ramirez, Michael K. Appelhans

JTRP Technical Reports

In Volume 4 of the final report, the results of an evaluation of the bond performance of epoxy-coated bars with a coating thickness up to 18 mils are presented. The experimental work on the bond performance of epoxy-coated bars with thickness up to 18 mils indicates that the current AASHTO requirements for development length of epoxy-coated bars up to #8 could be safely extended to coating thickness of up to 18 mils. Thus, no change to the bond specifications is recommended in order to implement the use of bars with diameters up to a #8 with epoxy-coating thickness up to …

Performance-Related Specifications For Concrete Bridge Superstructures, Volume 3: Nonmetallic Reinforcement, Robert J. Frosch, Christopher P. Mosley, Ahmet Koray Tureyen

JTRP Technical Reports

In Volume 3 of the final report, research work conducted to investigate the behavior of fiber reinforced polymer (FRP) reinforcement is summarized. This study focused on the behavior of FRP reinforced concrete structures with an emphasis on bond and shear. For the bond investigation, three series of beam splice tests were performed on specimens reinforced with steel, glass FRP, and aramid FRP to determine the effect of the different types of reinforcement on bond, cracking, and deflections. The test results indicate that the use of FRP reinforcement leads to lower bond strengths and, therefore, require longer development lengths. The specimen …

Development And Evaluation Of Cement-Based Materials For Repair Of Corrosion-Damaged Reinforced Concrete Slabs, Rongtang Liu, J. Olek

JTRP Technical Reports

In this study, the results of an extensive laboratory investigation conducted to evaluate the properties of concrete mixes used as patching materials to repair reinforced concrete slabs damaged by corrosion are reported. Seven special concrete mixes containing various combinations of chemical or mineral admixtures were developed and used as a patching material to improve the durability of the repaired slabs. Physical and mechanical properties of these mixes, such as compressive strength, static modulus of elasticity, dynamic modulus of elasticity, and shrinkage were evaluated. Durability-related parameters investigated included resistance of concrete to penetration of chloride ions and freeze-thaw resistance. The results …

Performance Of Bridge Decks And Girders With Lightweight Aggregate Concrete, V. 2 Of 2, J. A. Ramirez, J. Olek, Eric Joseph Rolle, Brian Joseph Malone

JTRP Technical Reports

Structural lightweight concrete is a very versatile material and Haydite and Minergy lightweight aggregates can be utilized in the mixture development of concrete for use in girders and decks in bridges. More widespread use of lightweight aggregates (LWA) would result in savings in construction cost due to considerable dead load reduction.

The materials phase of this research study evaluated the fresh concrete properties (slump, unit weight, and air content), the mechanical properties of hardened concrete (compressive strength, tensile strength, flexural strength, static and dynamic modulus of elasticity, Poisson’s Ratio, and temperature development), and durability related parameters (air void distribution, freeze-that …