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Effect of Boron Active Belite Cement on the Compressive Strength of Concrete Exposed to High Temperatures
Abdulkadir Cüneyt Aydın,
Ülviye Gülsüm Haşiloğlu Aras,
Türkay Kotan,
Ali Öz
Issue:
Volume 3, Issue 3, June 2018
Pages:
47-52
Received:
31 May 2018
Accepted:
21 June 2018
Published:
16 July 2018
Abstract: The boron active belite (BAB) cement is a cement type different from Portland cement due to the presence of B2O3 at 3-4%, low hydration temperature, low early strength and high final strength. In this study, concretes with three similar gradations were produced using BAB, CEM I 42.5 and CEM II 32.5 cements. Prepared cylindrical (Ø100/200 mm) concrete samples were exposed to high temperatures of 200, 400 and 600°C at the end of 7th, 28th and 90th days of standard water curing periods. Then, the compressive strength, ultrasonic pulse velocity and Schmidt hammer strength properties of the concretes were investigated to determine their resistance to high temperatures. As a result, the compressive strength values of concrete with BAB cement were found to be higher in the final period than in concrete with normal Portland cement. Therefore, it can be said that the concretes produced with BAB cement is more durable against elevated temperatures from concretes produced with normal Portland cement. Moreover, the observed strength differences in concretes with BAB cement, were discussed in the light of current information in the literature.
Abstract: The boron active belite (BAB) cement is a cement type different from Portland cement due to the presence of B2O3 at 3-4%, low hydration temperature, low early strength and high final strength. In this study, concretes with three similar gradations were produced using BAB, CEM I 42.5 and CEM II 32.5 cements. Prepared cylindrical (Ø100/200 mm) concre...
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Application of BIM Technology in the Drawing Deepening Stage of China Port Museum
Wang Zhanliang,
Tian Xiugang
Issue:
Volume 3, Issue 3, June 2018
Pages:
53-63
Received:
5 June 2018
Accepted:
6 July 2018
Published:
1 August 2018
Abstract: Combined with the project of China Port Museum, the Paper has mainly introduced the application of BIM technology in the stage of deepening design of complex architecture projects. Through the three-dimensional model, it can quickly find and solve the contradictions and design mistakes in the drawings, having perfected the structure system, optimized the details, improved the efficiency and accuracy of the project’s deepening design and guaranteed the correctness of the subsequent component processing and the smooth progress of site installation.
Abstract: Combined with the project of China Port Museum, the Paper has mainly introduced the application of BIM technology in the stage of deepening design of complex architecture projects. Through the three-dimensional model, it can quickly find and solve the contradictions and design mistakes in the drawings, having perfected the structure system, optimiz...
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Behavior of Axially Loaded CFRP Confined Large-Scale Capsule-Shaped RC Short Columns with Higher Cross-Sectional Aspect Ratio
Abd El Rahman Megahid Ahmed,
Omar Ahmed Farghal,
Walied Ahmed Bazar
Issue:
Volume 3, Issue 3, June 2018
Pages:
64-77
Received:
4 July 2018
Accepted:
12 July 2018
Published:
7 August 2018
Abstract: This paper aimed to experimentally and analytically investigate the behavior of reinforced concrete (RC) short capsule-shaped columns confined with carbon fiber-reinforced polymer (CFRP) sheets. The efficiency of FRP-confined strengthening system depends mainly on different encountered parameters such as the FRP confinement ratio, shape and size of cross-section, and cross sectional aspect ratio of non-circular columns. The effects of varying the aspect ratio (h/b=2, 2.5, 3 and 4), FRP confinement ratio (number of FRP layers), and FRP-wrapping configuration (full and partial system) are examined in this study. The experiment results showed that the efficiency of FRP confined system was proven to be lower with higher aspect ratio than that with the lower aspect ratio. Confinement by CFRP sheets enhances the performance of capsule-shaped RC columns subjected to axial compressive loads, and it is an efficient technique to improve the strength and ductility of capsule shaped RC columns regardless the cross sectional aspect ratio and the type of confinement. Analytical model was proposed by the authors to predict the axial load carrying capacity of short capsule-shaped reinforced concrete columns. The proposed model is compared with the existing model, showing good agreement with the experimental results and it is improved performance and gives reasonable predictions of load carrying capacity of FRP-confined columns.
Abstract: This paper aimed to experimentally and analytically investigate the behavior of reinforced concrete (RC) short capsule-shaped columns confined with carbon fiber-reinforced polymer (CFRP) sheets. The efficiency of FRP-confined strengthening system depends mainly on different encountered parameters such as the FRP confinement ratio, shape and size of...
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Effect of Curing Methods on the Compressive Strength of Kenaf Stabilised ‘Green’ Lateritic Mortar
Temitope Oyeniran,
Olayinka Omotosho,
Babatunde Olanrewaju
Issue:
Volume 3, Issue 3, June 2018
Pages:
78-82
Received:
13 April 2018
Accepted:
7 May 2018
Published:
16 August 2018
Abstract: The study considered the effects of curing methods on the compressive strength of kenaf stabilised lateritic mortar at 1:5 and 1:10 cement-aggregate mix ratio. Composition of the mortar for each of the cement mix ratios was also substituted with kenaf fibres at 0, 0.5, 1.0, 1.5, 2.0 and 2.5% by weight. The effects of these factors on compressive strength of the green mortar revealed that at 1:5 cement mix, the values obtained from 28 days compressive strength of water cured samples revealed that, the kenaf replacement level should not exceed 1.0% while for air curing it should not exceed 1.5% in order to satisfy the ASTM C279 standard for O type mortar. However at 28 days the compressive strength of the samples at 1:10 cement mix did not meet the ASTM C279 standard for O and N type mortar thus indicating that binder strength was inadequate. In general the failure in kenaf fibrous mortar samples was observed to have been slow and gradual, compared to the instantaneous nature of failure observed in the pure cement-aggregate samples.
Abstract: The study considered the effects of curing methods on the compressive strength of kenaf stabilised lateritic mortar at 1:5 and 1:10 cement-aggregate mix ratio. Composition of the mortar for each of the cement mix ratios was also substituted with kenaf fibres at 0, 0.5, 1.0, 1.5, 2.0 and 2.5% by weight. The effects of these factors on compressive st...
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The Theory of Zero Incident Safety Management
Yin Wang,
Fletcher Griffis
Issue:
Volume 3, Issue 3, June 2018
Pages:
83-98
Received:
20 June 2018
Accepted:
7 July 2018
Published:
16 August 2018
Abstract: Despite the dramatic improvements in construction safety made over the past few decades, the construction industry as a whole is still nowhere near reaching the Zero Injury goal, let alone the Zero Incident goal. The purpose of this paper is to provide an approach to continue improvements of safety performance in order to reach the Zero Incident goal. Since the concept of "Zero Injury" emerged in the 1990s, increasing numbers of owners and contractors have achieved the Zero Injury goal on construction projects. The key to these achievements is the Nine Zero Injury Principles established by Construction Industry Institute (CII). However, the research on which the Nine Zero Injury Principles relied is questionnaire survey rather than theoretical analysis. Without theoretical analysis supporting the research, the conclusions are often challenged, making the concept of Zero Injury difficult to promote throughout the industry. Thus, there exists the need to develop the theory of Zero Incident Safety Management (ZISM) and re-define the concept of "Zero Incident" to provide theoretical insight into the practical application of ZISM techniques and make Zero Incident more acceptable. Drawing on previous theories of construction accident causation and prevention, a new update accident causation theory was developed. This research then identified the management factors that can eliminate the corresponding accident causation factors. Developing the theory of ZISM can not only helps construction leaders deeply understand and accept the concept of Zero Incident, but also guide how to make Zero Incident come true. To facilitate the most rapid implementation of the Nine Principles, a ZISM standard benchmark tool with leading metrics was created. This tool can be easily used to assess the extent of implementation of safety program in construction projects.
Abstract: Despite the dramatic improvements in construction safety made over the past few decades, the construction industry as a whole is still nowhere near reaching the Zero Injury goal, let alone the Zero Incident goal. The purpose of this paper is to provide an approach to continue improvements of safety performance in order to reach the Zero Incident go...
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