Development of High Strength Pervious Concrete Using Slag as the Aggregate

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簡歷

基本資料

Project title

Code/計畫編號

NSC99-2221-E019-034

Translated Name/計畫中文名

含爐渣之高強度透水混凝土研發

Project Coordinator/計畫主持人

Jiang-Jhy Chang

Funding Organization/主管機關

National Science and Technology Council

Co-Investigator(s)/共同執行人

葉為忠

Department/Unit

Department of Harbor and River Engineering

Website

https://www.grb.gov.tw/search/planDetail?id=2110428

Year

2010

Start date/計畫起

01-08-2010

Expected Completion/計畫迄

31-07-2011

Co-Investigator(s)

Wei-Chung Yeih

Bugetid/研究經費

573千元

ResearchField/研究領域

土木水利工程

"Liver cancers are fatal to our health. Detecting liver cancers is crucial for curing the diseases. Blood-testing, CT scan images, MRI images, and Ultrasound images are useful methodologies for detecting liver cancers. However, blood-testing can only be used to survey the functionalities of our livers. It can not be utilized to locate cancer cells or estimate the size of cancer tissues. CT and MRI images can offer high-resolution portrays of our livers. They are very useful for surgical assessment and planning. Nonetheless, the high-dose X-ray radiation used in CT scan may cause cancers in the future. This method should not be employed unless it is un-avoidable. MRI-imaging is very expensive. Taking MRI images requires a lot of efforts too. Doctors can not perform MRI scanning too often. They can not take MRI images in their clinical examination procedures unless they have a team of engineers to help them. Compared with other medical imaging methods, ultrasound-imaging is easy to conduct and less expensive. Unlike CT scan, it is un-intrusive and causes very little side-effects. Doctors can take ultrasonic images if the medical procedures require the revealing of some special organs and tissues. Thus ultrasound imaging is widely used for detecting liver cancers and tracing the results of treatments or surgeries. One major problem reduce the usefulness of ultrasound imaging, the speckle noises in ultrasound images. Speckles are created by the constructive and destructive interferences of sound beams. They come with ultrasound images. They block insight data such that it is difficult to obtain clear displays of our internal organs and tissues. In this research, we propose a structure-based approach to post-process ultrasound images. At first, we create a set of hierarchical data set. Then the diffuse tensor field of the data is computed at each level of data. The eigen-vectors and eigen-values of the tensor field are used to detect the underlying structure in each region. Then based on the shapes and sizes of the structures, adaptive filters are used to enhance features and suppress noises. The structure information obtained in all levels are combined to form the full description and profile of the entire 3D ultrasound data volume. We do not intend to reconstruct the geometries of livers. Instead, advanced volume rendering methods will be employed to display the fine details of livers. Beside cancer cells, we will pay more attention to the linear structures, for example, blood veins since they are vital for surgical planning. The major goals of the research include: 1. Design and test a 3D structure analysis procedure for 3D ultrasonic data sets. 2. Improve current filtering methods such that more linear structures and cancer cells are preserved while speckles are reduced. 3. Create a post-processing system to help doctors" "Because of the development of human civilization, earth of urban zone is largely covered by impermeable pavements which make the interchange of heat and water between air and earth is blocked and consequently it results in the so-called heat island effect. In addition, the impermeable pavement cannot have flood control capability as the permeable pavement does. Due to the abovementioned reasons, the development of permeable pavement becomes an important topic worldwide. However, it is well known that the strength of permeable pavement is not high enough due to its higher porosity. Due to that, the permeable pavement nowadays is used for low-transportation road pavement, park and parking lot. If we can enhance the strength of permeable pavement, it is then able to be used for highway pavement and airport runway. Besides of the permeable pavement, the high strength pervious concrete can also be used for concrete members that require strength and permeability at the same time such as the slope protection, river bank and so on. In the previous design concept of pervious concrete, the path of water is through the paste and the aggregate is used as filler. Therefore, the paste/void volume ratio is controlled as 70%~90% such that the permeability coefficient can exceed 1.0×10-2 cm /sec. In this study, we propose a different concept: using the porous slag as the aggregate. This idea can extend the path of water to aggregate as well such that one can use higher paste/void volume ratio and the strength of concrete can be enhanced. In addition, the pozzolan reaction between the hydration products and slag aggregate should increase strength. Also, the paste will penetrate into the aggregate and after it is harden the interlock effect will contribute to the increment of strength. However, it is well known that the slag should not be used to make concrete due to its expansive property. This problem is trickily avoided in pervious concrete because the designed unfilled voids will allow the expansion of aggregates. To make the high strength pervious concrete, the alkali-activated slag paste is used to replace the ordinary Portland cement paste sine the strength of the alkali-activated slag paste is known to be higher than the cement paste. According to these, we propose a two-year research proposal to develop the high strength pervious concrete. It is expected that the research results can be applied to any concrete members requiring strength as well as permeability. The goals of two years are listed in the followings: (1) The first year: to use the cement paste as the binder and slag as the aggregate to make higher strength pervious concrete; (2) The second year: to use the alkali-activated slag paste as the binder and slag as the aggregate to make high strength pervious concrete. It is expected that the results of this research can be applied in various engineering projects where the high strength pervious concrete is required."

Keyword(s)

透水混凝土
爐渣
鹼活化爐石漿體
pervious concrete
slag
alkali-activated slag paste

DSpace CRIS

Development of High Strength Pervious Concrete Using Slag as the Aggregate

基本資料

Description