Thermal stress cracking prediction in a thick slab in an underground powerhouse | |
| Author | Lee, Chin-chun |
| Call Number | AIT Thesis no. ST-93-8 |
| Subject(s) | Thermal stresses Concrete slabs Concrete--Cracking |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Civil Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | The current interest of civil engineers in predicting the occmTence of thermal stress cracks is the author's concern in this study . For most civil engineers, the fact that thermal stress cracks will take place in massive concrete without any special preventive procedure is a common sense. However, the quantification of the prediction of the risk of thermal stress cracking has not been made until the Subcommittee on Thermal Stress in Massive Concrete of Japan Concrete Institute (JCI) developed a package (call MCTC) for estimating the risk of thermal stress cracking in a massive concrete. In this study, the author utilized the package as a tool to predict whether a thick slab (t=95 cm) in an underground powerhouse will suffer thermal stress cracks or not, and compared the analyzed results with the real situation in the field. In order to find out the procedure for preventing the thermal stress- induced cracks to take place on a similar slab to the one in this study in future, the author tried several combinations by changing the type of cement, the unit cement content, the concrete placing temperature, the air temperature and lessening the restraint of slab with sidewalls. Despite the limitation of the capacity of two dimension analysis for MCTC , the author develop a series of program to overcome the difficulty of transfen-ing 2-D to simplified 3-D. Finally, it was confomed that thermal stress played a primary role in causing cracks for this slab. Through employing MCTC, the solution for preventing the occurrence of thermal stress cracking was obtained. From this study, the author achieved the following keynotes: 1. Definition of massive concrete becomes clearer. 2. It has been successfully to predict whether or not thermal stress crack will take place in a thick slab by application of MCTC. 3. To set up a series of procedures by which engineers can adopt some appropriate treatments has been put into practice. |
| Year | 1993 |
| 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) | Aoyagi, Yukio |
| Examination Committee(s) | Karasudhi, Pisidhi ;Pichai Nimityongskul |
| Scholarship Donor(s) | Ministry of Economic Affairs, R.O.C |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1993 |