Structural Concrete, Vol. 12, no. 1, March 2011

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International code harmonization: the role of the Asian Concrete Model Code

Tamon Ueda, Hokkaido University, Japan

Many national codes in Asia are heavily influenced by those from either Europe or the USA. The climatic, technological and economic conditions together with the material properties in Asia are, however, quite different from those in Europe and the USA, and even different among Asian countries. Thus, many Asian countries need their own national codes with suitable concepts and technologies. At the same time, many construction projects in Asia are carried out in multi-national environments in which various national codes are applied, meaning that international code harmonization is necessary. In order to work for the global issue, such as the construction of a sustainable world, Asia, as the largest economic zone in the 21st century, should take on a leading role. For this purpose, international code harmonization with the new direction of life cycle man- agement (LCM) would provide an efficient way.

The International Committee on Concrete Model Code for Asia (ICCMC) was established in 1994 as the first international body in Asia. The ICCMC issued the Asian Concrete Model Code (ACMC) in 2001, the first international structural code in Asia. The ACMC is an umbrella code with a performance-based concept and a multi-level document structure, which makes it suitable for the considerable diversity in Asia. It is also the first international code covering maintenance and repair, which makes the ACMC ready to adopt the LCM concept. The ACMC has been a model for various national codes. The main features of the ACMC, i.e. the performance-based concept, durability design concept, seismic design concept and the inclusion of maintenance/repair, are shared with JSCE Standard Specifications in Japan. The ICCMC has been working together with ISO/TC71 towards international code harmonization.

Structural Concrete, Vol. 12, no. 1, March 2011

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Life cycle assessments of concrete structures - a step towards environmental savings

Petr Hajek, Czech Technical University in Prague, Czech Republic
Ctislav Fiala, Czech Technical University in Prague, Czech Republic
Magdalena Kynclova, Czech Technical University in Prague, Czech Republic


Considering the volume of concrete produced and the number of concrete structures built, the problem of the associated environmental impact forms a significant part of the entire global problem of sustainable development. Utilization of environmentally optimized concrete structures thus creates a potential for increasing the quality of construction and consequently a reduction of the environmental impact. A life cycle assessment (LCA) is a complex, multi-parametric assessment of the environmental impact of the structure over its whole life cycle. It covers, in one assessment process, all the essential environmental issues, including CO2 emissions, energy consumption, water consumption, waste generation, etc. In the case of concrete, selected criteria should support the design and construction of high-quality and at the same time environmentally friendly concrete structures. The principal problem is to collect relevant environmental input data for specific concrete types plus transport and production processes which can be used in the LCA procedure.

Structural Concrete, Vol. 12, no. 1, March 2011

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Structural systems for protection against extreme events

Klaas van Breugel, Delft University of Technology, The Netherlands


Typical for extreme events is their multidisciplinary nature, and, consequently, solutions for protection against extreme events should mirror their inherent characteristics. This article discusses different types of hazards and extreme events in order to illustrate the complexity and scale of the problem. Concepts for judging hazards and associated risks are dealt with. Some features of the traditional risk concept are discussed, followed by a proposal for an extended risk concept, to be applied when dealing with extreme hazards. The emphasis will be on aspects that are typical of "low-probability/high-consequence risks", particularly industrial risks. The potential role of structural (concrete) protective systems for mitigating the consequences of industrial accidents is emphasized. Throughout this article, the role of structural designers and their possible contribution to the debate on adequate protection against extreme events is addressed.

Structural Concrete Contents for Volume 9 (2008)

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No. 1, March
No. 2, June
No. 3, September
No. 4, December

No. 1, March 2008 - Contents

  1. Editorial
    P.G. Gambarova
  2. Recent development in fire design of concrete structures
    N.P. Høj
    Abstract     Article
  3. Concrete spalling assessment methodologies and polypropylene fibre toxicity analysis in tunnel fires
    G.A. Khoury
    Abstract     Article
  4. Today's concretes exposed to fire-test results and sectional analysis
    P. Bamonte, P.G. Gambarova and A. Meda
    Abstract     Article
  5. Non-linear and plastic analysis of RC beams subjected to fire
    P. Riva and J.-M. Franssen
    Abstract     Article
  6. Flexural response of reinforced concrete beams exposed to fire
    V. Kodur and M. Dwaikat
    Abstract     Article
  7. Mass transport through concrete walls subjected to high temperature and gas pressure
    A. Laghcha, G. Debicki and B. Masson
    Abstract     Article

No. 2, June 2008 - Contents

  1. Editorial
    K. Sakai
    Article
  2. An experimental investigation on beam supported reinforced concrete skew slabs
    K. U. Muthu, M. U. Aswath, A. Prabhakara
    Abstract     Article
  3. A finite element formulation for concrete structures in plane stress
    G. Bertagnoli, V. I. Carbone
    Abstract     Article
  4. Strength and durability of high-volume fly ash concrete
    G. Baert, A.-M. Poppe, N. De Belie
    Abstract     Article
  5. Mechanical properties of high-volume fly ash self-compacting concrete mixtures
    P. Dinakar, K. G. Babu, M. Santhanam
    Abstract     Article

No. 3, September 2008 - Contents

  1. Editorial
    S. Helland
    Article
  2. Bond behaviour of NSM FRP strips in service
    K. Borchert, K. Zilch
    Abstract     Article
  3. Analysis and cost optimisation of prestressed concrete joists in beam-block floors
    V.C. de Castilho, M.C. Vidigal de Lima
    Abstract     Article
  4. Load carrying capacity of cracked concrete railway sleepers
    H. Thun, S. Utsi, L. Elfgren
    Abstract     Article
  5. Effect of grout proportions on strength of two-stage concrete
    H.S. Abdelgader, A.A. Elgalhud
    Abstract     Article

No. 4, December 2008 - Contents

  1. Concrete coating for marine pipelines
    M. Braestrup
    Abstract     Article
  2. Post-heating bond behaviour between lightweight fibrous concrete and steel
    R.H. Haddad, Z.G. Al-Kofahi
    Abstract     Article
  3. Engineering the construction of the Stonecutters Bridge concrete backspans
    G. Morgenthal, R. Sham, K. Yamane
    Abstract     Article
  4. Fatigue life of short-span reinforced concrete railway bridges
    M. Pimentel, E. Brühwiler, J. Figueiras
    Abstract     Article

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Structural Concrete, Vol. 11, no. 4, December 2010

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Utilisation of olive waste ash in mortar mixes

N. M. Al-Akhras, University of Dammam, Dammam, Saudi Arabia
M. Y. Abdulwahid, Koya University, Kurdistan Regional, Iraq

Huge amounts of olive waste residues are accumulated every year in olive-oil-producing countries, making an environmental impact. This study investigates the utilisation of olive waste ash in mortar mixes to reduce the environmental pollution arising from olive waste residue. Three olive waste ash levels were considered in the study: 5, 10 and 15%. The other experimental parameters investigated in the study were: replacement type (cement or sand), curing type (moist and autoclaving) and aggregate type (silica and limestone sand). The properties investigated in the study include: fresh properties (workability and setting time), mechanical properties (compressive and flexural strength) and microstructure of mortar. The mortar mixture proportions were 1: 3: 0.7 by weight for cement, sand and water, respectively. The results showed that the setting time and workability of mortar decreased with increasing the olive waste ash content. The mechanical properties of mortar increased with increasing the olive waste ash content as a partial replacement for the sand. On the other hand, the compressive and flexural strength of mortar decreased when more cement was replaced with olive waste ash. The mechanical properties of olive waste ash mortar using silica sand showed higher values compared to those using limestone sand. Scanning electron microscopy images show that the hardened matrix of mortar containing 15% olive waste ash as a partial replacement for silica sand was denser and had a more homogeneous microstructure in comparison with the reference and mortar mixes with olive waste ash as cement replacement. 

 

Structural Concrete, Vol. 11, no. 4, December 2010

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Strength properties of HPC using binary, ternary and quaternary cementitious blends

K. Chinnaraju, Anna University, Chennai, Tamilnadu, India
K. Subramanian, Coimbatore Institute of Technology, Coimbatore, Tamilnadu, India
S. R. R. Senthil Kumar, P.P.G. Institute of Technology, Saravanampatti, Coimbatore, Tamilnadu, India

Use of high-performance concrete for structural applications has grown substantially in recent years. This paper focuses on studying the effect of different supplementary cementitious materials (silica fume, fly ash, ground granulated blast furnace slag, and their combinations) on strength characteristics of high-performance concrete. An experimental test programme was conducted to study the effect of such admixtures on compressive strength at 7 days and 28 days, splitting tensile and flexural tensile strengths at 28 days for high-performance concrete. A set of 60 different concrete mixtures were cast and tested with different cement replacement levels (0, 10, 20 and 30% by weight of cement) by various combinations of fly ash and ground granulated blast furnace slag with silica fume as addition (0, 2.5, 5, 7.5, 10 and 12.5% by weight of cement) for each combination. Super plasticiser was added at different dosages to achieve a constant range of slump for desired workability with a constant water-binder (w/b) ratio. Based on the test results the influence of such admixtures on strength aspects were critically analysed and discussed. A regression analysis has been carried out to relate compressive strength to flexural and splitting tensile strengths. 

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