Developing Taiwan''s Concrete Creep Prediction Formulae Based on the Establishment and Application of Database

• Main Authors: Ting-Kai Liu, 劉庭愷
• Other Authors: Jenn-Chuan Chern
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/f4357r

碩士 === 國立臺灣大學 === 土木工程學研究所 === 105 === Tests and researches on the creep and shrinkage of concrete have been developed over several decades at various places around the world. Northwestern University (NU) of the USA has established a concrete deformation database which incorporates data from around the world, while the Japan Society of Civil Engineers has established their own such database with date from Japan. National Taiwan University (NTU) began collecting data from Taiwan and established a first-version database in 2001. Continuing the early work done at NTU, this study follows the framework and formula of the NU database in establishing the Taiwan Creep and Shrinkage Database, the purpose of which is in collecting and integrating up-to-date local data on shrinkage and creep. Some distinct local characteristics of concrete in Taiwan have been discovered after a comparison between international and Taiwan-only data. The local concrete produced is generally made with a high amount of cement, low water-to-cement ratio, as well as low elastic modulus of sandstone aggregate. This study takes the Model B4 creep prediction model as a base for the development of a local prediction model for Taiwan. Modifications to the model, where necessary, primarily concern the underestimation of the concrete elastic modulus due to local aggregate, large deformation due to high paste amount, and the influence of low elastic modulus of aggregate to drying creep. Due to the lack of data for slag and fly ash concrete creep in the Taiwan database, suggestions for further experiments are proposed to promote the formulation of prediction formulae. Rather than traditional methods, this study uses new tools for database establishment and analysis, and combines them in a new procedure. The new procedure involves MySQL, a Database Management System, for database establishment, and Python, a programming language, for programing of analysis models and post-processing tasks. Results show that this new database processing procedure is much more efficient than traditional procedures. This is, first, due to the greater efficiency of MySQL and Python over traditional Database Management Systems and programming languages. Second, SQL (the database programming language behind MySQL) is highly portable, which facilitates integration between MySQL and Python. Third, professional packages in Python allow one to proceed with many steps of analysis and post-processing automatically. It is foreseen that this study will help to incorporate the Taiwan database into the world concrete deformation database and will help to establish an effective platform based on MySQL and Python. This, in turn, is expected to promote the development of a new era of cloud calculation and user-friendly web systems for deformation prediction.