| Author | Theradej Litsomboon |
| Call Number | AIT Thesis no.ST-08-06 |
| Subject(s) | Lightweight concrete
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| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. ST-08-06 |
| Abstract | The purpose of this research is to determine how feasible the use of different lightweight materials and bottom ash are as coarse and fine aggregates when materials in concrete are replaced with and without fly ash. The lightweight materials were composed of 6 types, namely pumice, Siriwan lightweight aggregate, polypropylene (PP) and high¬density polyethylene (HDP), anthracite coal and MTEC lightweight aggregate. The crushed limestone concrete was used to determine and perform the testing of properties as a reference control mix concrete. The experimental program was divided into two parts. First part dealt with a preliminary study of determining the types of appropriate lightweight materials to replace the crushed lime stone. The second part was the main testing which was performed to study the effect of fly ash and superplasticiser and the possibility of using bottom ash as a fine lightweight aggregate. The tests for physical and mechanical properties of lightweight aggregate concretes (L WAC) were conducted namely, workability, compressive strength, apparent density, abrasion resistance and absorption. Test results showed that MTEC LA had achieved both low density and high compressive strength. Although pumice, Siriwan LA and polypropylene had disadvantages in compressive strength, the criteria for low-density concrete were satisfied. While the unit weight of lightweight concrete made out of HDP was rather high, their compressive strength and the strength to density ratio were higher compared with the others. The compressive strength of L WAC increased with an increase in density but, depending on the type of aggregate. The replacement of normal weight sand with bottom ash resulted in a decrease both in density of concrete by 180-225 kg/m³ and 28-day compressive strength of concrete by 16-26%. Moreover, the use of bottom ash to replace sand in concrete increased the demand for mixing water to obtain the require workability due to its porosity and shape. The type and absorption of lightweight aggregates (LA) influenced predominantly the water absorption of L W AC. Total replacement of natural sand by bottom ash increased the absorption of the concrete by 63-90%. With regard to abrasion resistance, the abrasion resistance of L W AC was mainly dependent on the compressive strength of concrete: the higher the strength, the higher the abrasion resistance of L WAC. However, high water absorption of concrete caused a reduction in the abrasion resistance. In addition, the use of bottom ash as a fine aggregate resulted in a lower abrasion resistance of L W AC due to its porosity. |
| Year | 2008 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. ST-08-06 |
| Type | Thesis |
| School | School of Engineering and Technology |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Structural Engineering (STE) /Former Name = Structural Engineering and Construction (ST) |
| Chairperson(s) | Worsak Kanok-Nukulchai |
| Examination Committee(s) | Pichai Nimityongskul;Thanakorn Pheeraphan |
| Scholarship Donor(s) | Thailand (HM King) |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2008 |