Experimental Analysis of Fracture and Damage Mechanics of Pre-Stressed Concrete Sleepers B70: Part B- Analysis

نویسندگان

  • Fereydoon Rezaie Associate Professor, Department of Civil Engineering, Bu-Ali Sina University, Hamedan, Iran
چکیده مقاله:

Initial cracks occur in high strength concrete sleepers for various reasons, such as shrinkage and wrong curing and long lifetime of over 50 years of sleepers. These cracks may lead to complete failure of the structure. In order to more accurately design the sleepers, fracture mechanics (not strength of materials) should be incorporated. In order to achieve this purpose, it is important to forecast crack growth and residual strength reduction rate. In this study, based on the principles of nonlinear fracture mechanics (NLFM) in concrete material, fracture behavior of pre-stressed concrete sleepers was investigated. Sleepers with the lengths of initiation crack of 5 mm with 10 mm step increasing to 45 mm were tested. Five specimens in each group were loaded under three-point bending test, in order to calculate Ic K , crack growth, and load-displacement diagram. The results showed that by increasing the crack-to-depth ratio, initial toughness, crack stability, and crack unstable toughness, the crack instability expansion begins. By increasing the crack-to-depth ratio, both initial and unstable toughness values increased linearly versus LEFM theory. Damage begins with an initial crack like in flexural damage and then continues with bifurcation of the crack. The influence of shear damage in sleeper's crack growing leads it to the ultimate damage.

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

experimental analysis of fracture and damage mechanics of pre-stressed concrete sleepers b70: part b- analysis

initial cracks occur in high strength concrete sleepers for various reasons, such as shrinkage and wrong curing and long lifetime of over 50 years of sleepers. these cracks may lead to complete failure of the structure. in order to more accurately design the sleepers, fracture mechanics (not strength of materials) should be incorporated. in order to achieve this purpose, it is important to fore...

متن کامل

Part A- Experimental: Experimental Analysis of Crack Propagation in Pre-stressed Concrete Sleepers by Fracture Mechanics

This study investigates propagation of mode I crack in B70 pre-stressed concrete sleepers by fracture mechanics approach. A new experimental analysis is done for notched B70 pre-stressed concrete sleepers with Replica test and image analysis. A scanning electron microscope test (SEM) and an image analysis are applied for the Replica test in order to determine crack length and crack mouth openin...

متن کامل

part a- experimental: experimental analysis of crack propagation in pre-stressed concrete sleepers by fracture mechanics

this study investigates propagation of mode i crack in b70 pre-stressed concrete sleepers by fracture mechanics approach. a new experimental analysis is done for notched b70 pre-stressed concrete sleepers with replica test and image analysis. a scanning electron microscope test (sem) and an image analysis are applied for the replica test in order to determine crack length and crack mouth openin...

متن کامل

Cracks Analysis in Zavin Concrete Dam Using Fracture Mechanics Approach

Most of the existing concrete dams are subjected to cracking. These cracks are caused by various factors such as construction practices, curing, loads and volume change of mass concrete which reduce the efficiency, failure or instability of concrete dams. Using fracture mechanics as a new method to estimate stability and durability of concrete dams is recommended in scientific publications in w...

متن کامل

langauge needs analysis of undergraduate business management and economics students

the aim of conducting this study was to investigate the foreign language learning needs of undergraduate economics students and business management students in faculties of social sciences of alzahra and azad naragh university. in the study, which was designed on the basis of a qualitative-quantitative basis using interviews and questionnaires, 146 female undergraduate business management as we...

15 صفحه اول

‏‎a phonological contrastive analysis of kurdish and english‎‏

deposite the different criticisms on contrastive analysis it has been proved that the results of it(when processed)can be usuful in a tefl environment,specially at the level of phonology.this study is an attempt to compare and contrast the sound systems of kurdish and english for pedagogical aims. the consonants,vowels,stress and intonation of the twolanguages are described by the same model-ta...

15 صفحه اول

منابع من

با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ذخیره در منابع من قبلا به منابع من ذحیره شده

{@ msg_add @}


عنوان ژورنال

دوره 5  شماره 1

صفحات  17- 29

تاریخ انتشار 2017-07-01

با دنبال کردن یک ژورنال هنگامی که شماره جدید این ژورنال منتشر می شود به شما از طریق ایمیل اطلاع داده می شود.

میزبانی شده توسط پلتفرم ابری doprax.com

copyright © 2015-2023