The strength and durability against acidic attack of fly ash concrete containing superplasticizers | |
| Author | Sumon Kaingkaew |
| Call Number | AIT Thesis no.ST-94-27 |
| Subject(s) | Fly ash Concrete--Testing |
| Note | A th1esis submitted in pa1tial fulfillment of the requirements for the degree of Master of Engineering, School of Civil Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | This experimental investigation deals with the durability of concrete subjected to 5 % solution of sulphuric acid and 5 % solution of hydrochloric acid. Different concrete mixes were prepared by using different fly ash replacements and different types of superplasticizer. Fly ash was obtained from the Mae Moh lignite power plant. Control concrete used for comparison was made by using ordinary Portland cement. The prope1ties of concrete subj1~cted to acids which were investigated were compressive strength, flexural strength, loss in weight, modulus of elasticity and scaling resistance by visual inspection. Cementitious materials of 450 Kg. per cubic metre was used and kept constant for all mixt::s. The percentages of fly ash replacement used in this study were 20 %, 35 % and 50 %. Two types of superplasticizer, namely melamine base superplasticizer and naphthalene base superplasticizer were used and the dosage of both superplasticizers was 1.65 % by weight of cementitious materials. Test results indicated that fly-ash concrete without using superplaticizer resulted in low early strength. If superplasticizer is used, the low early strength of fly-ash concrete can be significantly improved. For long-te1m strength, concrete having fly ash showed compressive strength higher than that of normal concrete. If superplasticizer is added, the long-term strength can be further improved. For both types of superplasticizer, the use of 20 % and 35 % fly ash replacement resulted in the highest gain in early and long-term strength respectively. Concrete containing naphthalene base superplasticizer resulted in strength approximately 10 % higher than concrete containing melamine base superplasticizer at all ages. With regard to acid attack, the weight loss of concrete without superplasticizer was found to decrease with increasing fly ash replacement. For fly-ash concrete containing superplasticizers, the weight loss of concrete was found to be slightly lower than fly-ash concrete without superplasticzer. The improvement was more significant for long exposure time than sho1t exposure time. The attack caused by sulphuric acid on concrete was found to be more severe than that caused by hydrochloric acid. |
| Year | 1994 |
| Type | Thesis |
| School | School of Civil Engineering |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Structural Engineering (STE) /Former Name = Structural Engineering and Construction (ST) |
| Chairperson(s) | Pichai Nimityongskul |
| Examination Committee(s) | Karasudhi, Pisidhi ;Aoyagi, Yukio ; Somnuk Tangte1msirikul |
| Scholarship Donor(s) | The Royal Thai Government |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1994 |