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  • 1
    In: MATEC Web of Conferences, EDP Sciences, Vol. 258 ( 2019), p. 05007-
    Abstract: The use of high strength reinforcing bars has becoming an interesting and cost-efficient option in construction industry recently. However, their use is limited due to their low deformability which might induce a brittle collapse in the structures. Also, longer development length is needed to transfer stress from reinforcing bars to the surrounding concrete. This paper focuses on investigating the influence of fibrous concrete and high-strength reinforcing bars on the behavior of structural elements. Five half-scaled specimens of interior joints using plain or fibrous concrete, reinforced with conventional 420 MPa or high strength reinforcing bar of 520 Mpa were experimentally tested. The two specimens of plain concrete, reinforced longitudinally with 16 mm and 19 mm reinforcing bars are defined as control specimens. The other test specimens were casted with Polypropylene fiber reinforced concrete (PFRC) with 16 mm and 19 mm longitudinal reinforcing bar. Loading protocol of all test specimens is defined according to ACI 374.2. The structure behavior, such as dissipated energy, bond between reinforcing bars and surrounding concrete, and stiffness degradation of the four specimens were evaluated and compared. The results obtained shows that the use of fiber increase the dissipated energy up to 27.5 % compared to specimens with plain concrete. Moreover, the peak strength of PFRC specimens was slightly increased (3% - 7%) compared to that of specimens with plain concrete. Moreover, there is an increase in peak-to-peak stiffness at elastic range loading with the addition of fiber, while no significant difference after the yields of longitudinal reinforcing bars.
    Type of Medium: Online Resource
    ISSN: 2261-236X
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2019
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  • 2
    In: MATEC Web of Conferences, EDP Sciences, Vol. 258 ( 2019), p. 02011-
    Abstract: This paper discusses the optimum seismic performance estimation analysis of the integrated multiple steel pipes bridge pier connected by shear panel damper (SPD). The optimization result to be expected to result in an easier structural design for the practical engineer. In this study, 405 different structural configurations with 35 and more variations of SPD thickness to be analyzed by non-linear static cyclic in order to quantify its energy dissipation. The optimum energy dissipation to be assumed as analogous with best objective seismic perfor- mance in order avoiding time consumption of numerical analysis. Furthermore, the SPD’s thickness related optimum energy dissipation of each structural configuration was successfully predicted by multi-parameter es- timation analysis with the artificial neural network (ANN) method. As the result, the R -value and the average error value of the estimated optimum SPD’s thickness compared with analytical result were 0.988 and 2.38%, respectively. With the estimated empirical equation result, the practical engineer could determine the structural configuration in the optimum seismic performance easily.
    Type of Medium: Online Resource
    ISSN: 2261-236X
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2019
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  • 3
    In: MATEC Web of Conferences, EDP Sciences, Vol. 258 ( 2019), p. 03008-
    Abstract: In order to establish objective criteria for road traffic accident (RTA) hotspots, this paper examines the application of three different hotspot analysis methods to both identify and rank the RTA hotspots. The three methods selected are the network Kernel Density Estimation (KDE+) method, the Getis-Ord GI* method, and a recently proposed risk-based method that accounts for RTA frequency, severity and socioeconomic costs - STAA method. The study road, Jalan Tutong, is a major dual-carriageway connecting major residential and commercial areas from the west of Brunei-Muara district and beyond to the capital, Bandar Seri Begawan. The RTA data consists of cases reported to the police during a 5-year period from 2012 to 2016. The RTA data were digitised and prepared, before being imported into ESRI ArcGIS 10.2 software for analysis using each of these methods. The outcomes, particularly the location, extent and priority of the RTA hotspots, are subsequently compared to results from road safety audits, in order to determine the relative merits and drawbacks of each method. The findings from the comparative study would be useful to recommend the most suitable method to identify and rank the RTA hotspots for the study road.
    Type of Medium: Online Resource
    ISSN: 2261-236X
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2019
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  • 4
    In: MATEC Web of Conferences, EDP Sciences, Vol. 258 ( 2019), p. 01009-
    Abstract: Fly ash-based geopolymer mortar normally achieves expected properties by heat curing. This becomes one of the obstacles for in-situ applications. The development of high calcium fly ash-based geopolymer mortar, suitable for ambient curing, will gain the applicability of such a material in civil structures. This article reports the results of an experimental study on mortar workability and the increasing of compressive strength of class C fly ash-based geopolymer mortar created in ambient curing condition. The main synthesis parameters such as alkali to the cementitious mass ratio varied from 30% to 40% by an increment of 5% and absolute volume of paste to absolute volume of voids of the aggregate ratio varied from 1 to 2 by an increment of 0.25. These parameters were designed to figure out their individual effects on mortar workability and the mechanical properties for the production of geopolymer mortar. The results suggested that the workability of mortar generally increased by using alkali to the cementitious mass ratio. The compressive strength of 60 MPa and the direct tensile strength of 2.8 MPa, the ratio of alkali to the cementitious mass of 0.35 and absolute volume of paste to absolute volume of voids of the aggregate ratio was 1.5; it was obtained at ambient temperature after 28 days of age. The results will be useful for developing the knowledge for the use of class C fly ash in producing geopolymer concrete, which is currently in progress. Hopefully, this contribution of research will improve the applications of such new binding material in the future.
    Type of Medium: Online Resource
    ISSN: 2261-236X
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2019
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  • 5
    In: MATEC Web of Conferences, EDP Sciences, Vol. 258 ( 2019), p. 05021-
    Abstract: In cold and snowy regions, frost damage happened in an RC bridge deck slab leads to horizontally layered cracks, which results in the disintegration of cover concrete. Since this deterioration mode occurs inside an RC slab, it is usually difficult to detect them. It is possible that the slab performances have already decreased when the deteriorations appear on the exterior surface. As a preliminary step towards the establishment of a method for evaluating the structural performance of such a damaged RC slab, the purpose of this paper is to investigate the relationship between deteriorations and structural behaviors and to study the effect of an epoxy injection repair. For simplification, RC beams are prepared with artificial cracks that simulate deteriorations and these were made by the use of expansive agent. These beams are tested in flexure. Since the damage is volumetric, image analysis is useful to capture the two-dimensional deformations. It is shown that with different deterioration depths that is a part of the compression side of the beam or full of the height, there are differences about the deformation behaviors, the repair effects and the distributions of maximum and minimum principal strain.
    Type of Medium: Online Resource
    ISSN: 2261-236X
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2019
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  • 6
    In: MATEC Web of Conferences, EDP Sciences, Vol. 258 ( 2019), p. 01013-
    Abstract: The applicability of bio-based materials for concrete repair has been studied. This technique employs yeast, glucose and calcium acetate mixed in Tris buffer solution. The microbial metabolic process leads to precipitation of calcium carbonate. First, this study investigated the applicability of bio-based repair materials to small-scale concrete specimens. On this research, water permeability test was carried out to evaluate the effectiveness of the selected mixtures for sealing cracks in the concrete specimens. As the result of permeability tests carried out using specimens with crack width of 0.6 mm, water leakage through crack was observed to be negligible after 216 hours by continuous pouring method using bio-based repair materials. Also, this study showed the initial flow rate for the specimens with the same crack width does not influence crack sealing time. Furthermore, the precipitation of the calcium carbonate from the bio-based materials was analyzed by Fourier-Transformed Infra-Red spectroscopy (FT-IR) and then examined by X-ray Diffraction (XRD) for mineral identification formed through the microbial metabolic process.
    Type of Medium: Online Resource
    ISSN: 2261-236X
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2019
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  • 7
    In: MATEC Web of Conferences, EDP Sciences, Vol. 258 ( 2019), p. 01015-
    Abstract: This study was conducted to investigate the effectiveness of concrete using sawdust to partially replace the river sand which could reduce both environmental problems and construction cost. In this study, sawdust concrete has been produced where the river sand is replaced with sawdust by 5%, 10% and 15% of the total sand volume. Both wet concrete and hardened concrete (cubes specimens) were tested through material testing and cube testing to obtain the most optimum sawdust concrete design. In addition, specimens have also been tested in environmental laboratory to identify the extent of hazardous use of sawdust to consumer health. This is because the dust used is the waste taken from the unknown root of the level of cleanliness. The result shows that the most optimum design for producing sawdust concrete is that with 10% replacement of river sand. The result is based on the compressive strength obtained. The results of environmental study also show that this sawdust concrete is free from any harmful to health contaminants.
    Type of Medium: Online Resource
    ISSN: 2261-236X
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2019
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  • 8
    In: MATEC Web of Conferences, EDP Sciences, Vol. 258 ( 2019), p. 01019-
    Abstract: A series of experimental programs was undertaken to investigate mechanical behaviour of bagasse ash stabilized organic soil. Preliminary experiment was done to verify the chemical and physical characteristics of bagasse ash and organic soil. The following experiment was then performed to study the improvement of unconfined compression strength of bagasse ash stabilized organic soil. In this research, three different organic soils and four different bagasse ashes were used. The soil was mixed with 10, 20 and 30% bagasse ash, then a set of unconfined compression tests were performed. In general, the results indicate that the unconfined compression strength of stabilized soil improve proportional to the percentage of bagasse ash. And, the quick lime content (CaO), ratio between quick lime and silica (CaO/SiO 2 ), and ratio between quick lime and the sum of silica and alumina {CaO/(SiO 2 +Al 2 O 3 )} were the fundamental factors affecting the improvement of bagasse ash stabilized soil unconfined compression strength. The significant improvement occurs on 0.25 〈 (CaO/SiO 2 ) 〈 1.00, and 0.20 〈 (CaO/(SiO 2 +Al 3 O 3 ) 〈 0.67. In contrast, organic content decreased unconfined compression, and maximum dry density (MDD) of stabilized soil. The addition of bagasse to the organic soil, however, does not significantly improve the unconfined compression strength, then addition of 6, 8, and 10% calcium carbide residue (CCR) was performed to the bagasse ash stbilized organic soil to get better engineering performance of stabilized soil. For 9% CCR, q u improve from 93 to 208 kPa.
    Type of Medium: Online Resource
    ISSN: 2261-236X
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2019
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  • 9
    In: MATEC Web of Conferences, EDP Sciences, Vol. 258 ( 2019), p. 01024-
    Abstract: In construction, concrete durability is an important material globally used in engineering, material of which can be applied in the fields of specialized marine construction. The ingress of chloride into concrete causes deterioration in the concrete due to the reinforcement corrosion. Adding bacteria into concrete can improve material properties and increase durability with mechanism resist chloride ingressed in the concrete . Ingress of Chloride into the concrete of bacteria is particularly suited for applications of chloride ion penetration in concrete. The objective of the research is to determine the effect of adding bacteria into the concrete properties. The bacteria used in this research is locally isolated and enriched to the suite with the concrete environment. The type of the bacteria used is identified as Sulphate Reduction Bacteria (SRB). The SRB added into the concrete mix with concentrations of 3%, 5% and 7%. Whereas, concentration of bacteria water of cement is 0.5. The mechanical properties test conducted with 28th, 56th, 90th, 180th and 360th day of curing period. The test was using cyclic wetting and drying to study the exposure to chloride condition, such as compressive strength, tensile strength and flexural test. Cubes in the size of 150 mm × 150 mm × 150 mm were prepared for compressive strength test and cylinder 150 mm × 300 mm were prepared for the tensile strength test. The flexural strength test was on the prism in the size of 100 mm × 100 mm × 500 mm. The result of compressive strength test shows, that gave significant strength of 66.3 MPa on the 360th day. The tensile strength and flexural strength have a similar trend as compressive strength results, where both results were optimum . The tensile strength test shows that 4.52 MPa tends to control 3.96 MPa. The result of flexural strength test was 8.23 MPa for compared to control of 5.99 MPa. The overall results of the bacteria indicate promising outcome and further study on chloride condition capability is encouraging.
    Type of Medium: Online Resource
    ISSN: 2261-236X
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2019
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  • 10
    In: MATEC Web of Conferences, EDP Sciences, Vol. 258 ( 2019), p. 02002-
    Abstract: The purpose of this study is to obtain the optimum geometric design and cross section member element of steel arch bridges. It is necessary because the geometric design of the steel truss arch bridges have the direct impact to the steel section used in the structures. Therefore, steel section have the impact to the economic value of the bridge design due to the structure weight. There are many important variables have to considered in the bridge design. Rise to span ratio variable is the major variable in the arch bridge geometric design. Arch bridge structures rely on the axial force capacity of the main arch, whereas shear forces and bending moments as secondary consideration. The optimization process is done by collecting the axial force, shear force and bending moment data of each steel arch bridge numeric model, and scaling its value from 0 to 1 to compare the data of every span in the same field, in order to achieve the optimum rise to span ratio. Rise to span ratio data of steel arch bridges in China and Japan used as the comparison with the result of this study, due to their brief history and rich experiences on arch bridge engineering innovation, and also have the large of amount of steel arch bridges. The results of this study give the optimum value of rise to span ratio between 1/4 to 1/7. It has good correlation with the rise to span ratio data of steel arch bridges in China and Japan i.e. 1/4 - 1/6 and 1/5 - 1/7 respectively.
    Type of Medium: Online Resource
    ISSN: 2261-236X
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2019
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