Evaluation of concrete structures of Bangladesh


INTRODUCTION
PROJECT DESCRIPTION
TIME FRAME
METHODOLOGY
CONCLUSIONS

INTRODUCTION

In the Asian region, the fragility of a structure, which is based on the defect of design criteria, inadequate construction management and maintenance management, etc., becomes to be a big problem.This study was undertaken by the Bangladesh Network office for Urban Safety (BNUS), Bangladesh University of Engineering and Technology and was supported by the International Centre for Urban Safety Engineering (ICUS), The University of Tokyo. The report presents the information of all the buildings including findings of reinforcement detailing of 14 RC buildings and Microtremor analysis of 17 RC and 29 Masonry buildings.

top
PROJECT DESCRIPTION

The aim of this project is to detect the earthquake vulnerability of BUET building by means of determining the location of the reinforcement and their spacing and Microtremor observation. So there are mainly two parts of the study. They are

  • Microtremor measurement
  • Detection of reinforcement
 

 

 

 

 

 

 

 

top
TIME FRAME

The study has been completed in two phases:

Phase 1: Survey and NDT of the buildings.

Duration: From June 15 to June 19, 2006; 5 days.

Phase 2: Data analysis

Duration: From June 20, 2006 to February 10, 2007

top
METHODOLOGY In order to identify correct dynamic properties, the most accurate approach is the direct measurement approach because the properties are derived from actual dynamic response of existing buildings. In recent years, several direct measurement techniques for determining the dynamic properties of structures have been developed. These techniques can be categorized into three basic methods
  • forced vibration method,
  • free vibration method, and
  • ambient vibration method.

    In this study ambient vibration method was used. Microtremor was used to assess soil characteristics

    		  
    Placing of sensor at the top of the building with proper direction   Inspection of building to make a decision for suitable placement of velocity sensor

top
CONCLUSIONS

In this study, the dynamic properties of low and medium-rise reinforced concrete buildings with various heights within BUET campus were investigated. The controlled human excitation was applied to amplify the ambient vibration responses in order to improve the accuracy of the identification of dynamic properties.

  • Amidst twenty nine masonry buildings natural period of eight buildings are not close to that of soil, so they are out of danger of resonance
  • Amidst seventeen RCC frame structure buildings natural period of four buildings are not close to that of soil, so they are out of danger of resonance
  • Some co-relation has been established for buildings in Bangladesh

top
BACK