THE EFFECT OF THE ENVIRONMENT ON BOND RESISTANCE BETWEEN CONCRETE AND STEEL REINFORCEMENT


THE EFFECT OF THE ENVIRONMENT ON BOND RESISTANCE BETWEEN CONCRETE AND STEEL REINFORCEMENT

CHAPTER ONE INTRODUCTION

1.1       BACKGROUND OF RESEARCH  

Reinforced concrete design is based on the assumption that concrete and steel reinforcement combines to create a new, composite material. Generally, the concrete is designed to carry the compressive loads while the reinforcing bar is designed to carry the tensile loads. There must be bond between the reinforcing bar and the concrete if it is to carry the tensile load and maintain equilibrium. However, bond between concrete and reinforcing bar is been affected by corrosion, a leading cause of structural failure. Reinforcing bar corrosion is a major concern in the world of concrete structures. It develops high pressure within the concrete causing the cracking and spilling of the concrete cover and the exposure of the reinforcing bar to further corrosion activity.

The Bond clause of the BS 8110 –1:1997 code is simply based on the compressive strength of concrete, a factor that could be expected to increase useable bond capacity. All other factors known to affect bonds were not taken into consideration. The ACI 318 (2002) code took various factors like concrete cover, diameter of bar, lap length, transverse reinforcement, spacing, transverse steel strength and the cylinder strength into consideration but the environment was not considered. The Eurocode EN 1992–1–1: 2004 (E) took various factors affecting bond into consideration including the environment and a factor of 0.7 of the normal bond strength was recommended in aggressive environment.

A developing country like Nigeria can adopt any code of practice but local specifications must be written to complement the adopted code. The lifespan and failure of structures especially reinforced structures has been of great concern to professionals and researchers in and out of the construction industry and over time, there has been a list of other factors that supposedly reduces the lifespan of structures or even possible failures. The environments where the reinforced structures are built affect the bond between concrete and steel reinforcement which in turn accelerates the performance loss of reinforced structures especially when reinforced concrete structures are located in aggressive environments, where they are exposed to corrosive fumes, seawater spray, abrasive actions, adverse weather conditions, etc. hence an attempt to study the effect of the environment on the bond between concrete and steel is desirable and worthwhile.

Not much work has been done on the effect of the environment on bond between concrete and steel reinforcement. This investigation is an attempt to generate data that can be used in developing local specification on the bond between concrete and steel reinforcement in aggressive environments like coastal and industrial, to be able to justify the use or otherwise of the recommended reduction factor of 0.7 in the Eurocode or to be able to recommend appropriate reduction factor in severe environments.

1.2       AIMS AND OBJECTIVES

The aim is to determine the effect of the environment on bond resistance between concrete and steel reinforcement. The objectives are to:

        i.            Generate data on the bond between concrete and steel reinforcement exposed to different environments (Normal, Coastal, and Industrial); and

      ii.            Compare the effect of each environment on the bond between the concrete and steel reinforcement.

1.3       SCOPE OF RESEARCH

Seventy-five (75) RILEM push-in specimens were cast. Twenty-five (25) specimens each were cast in the Normal, Coastal and Industrial environments, using 16mm high yield diameter bars in 160mm cube moulds. Three (3) control cubes were also cast to monitor the strength of concrete cast in each environment. All the materials used were exposed to the respective environment for fourteen (14) days. The RILEM specimens cast were cured in their respective environment for twenty-eight (28) days, and afterwards push-in tests were conducted to determine their bond resistances.

1.4       SIGNIFICANCE OF RESEARCH

The results of this present study would enhance the writing of local specifications for bonds in different environments.

 

.

THE EFFECT OF THE ENVIRONMENT ON BOND RESISTANCE BETWEEN CONCRETE AND STEEL REINFORCEMENT



TYPE IN YOUR TOPIC AND CLICK SEARCH.






RESEARCHWAP.NET
Researchwap.net is an online repository for free project topics and research materials, articles and custom writing of research works. We’re an online resource centre that provides a vast database for students to access numerous research project topics and materials. Researchwap.net guides and assist Postgraduate, Undergraduate and Final Year Students with well researched and quality project topics, topic ideas, research guides and project materials. We’re reliable and trustworthy, and we really understand what is called “time factor”, that is why we’ve simplified the process so that students can get their research projects ready on time. Our platform provides more educational services, such as hiring a writer, research analysis, and software for computer science research and we also seriously adhere to a timely delivery.

TESTIMONIES FROM OUR CLIENTS


Please feel free to carefully review some written and captured responses from our satisfied clients.

  • "Exceptionally outstanding. Highly recommend for all who wish to have effective and excellent project defence. Easily Accessable, Affordable, Effective and effective."

    Debby Henry George, Massachusetts Institute of Technology (MIT), Cambridge, USA.
  • "I saw this website on facebook page and I did not even bother since I was in a hurry to complete my project. But I am totally amazed that when I visited the website and saw the topic I was looking for and I decided to give a try and now I have received it within an hour after ordering the material. Am grateful guys!"

    Hilary Yusuf, United States International University Africa, Nairobi, Kenya.
  • "Researchwap.net is a website I recommend to all student and researchers within and outside the country. The web owners are doing great job and I appreciate them for that. Once again, thank you very much "researchwap.net" and God bless you and your business! ."

    Debby Henry George, Massachusetts Institute of Technology (MIT), Cambridge, USA.
  • "Great User Experience, Nice flows and Superb functionalities.The app is indeed a great tech innovation for greasing the wheels of final year, research and other pedagogical related project works. A trial would definitely convince you."

    Lamilare Valentine, Kwame Nkrumah University, Kumasi, Ghana.
  • "I love what you guys are doing, your material guided me well through my research. Thank you for helping me achieve academic success."

    Sampson, University of Nigeria, Nsukka.
  • "researchwap.com is God-sent! I got good grades in my seminar and project with the help of your service, thank you soooooo much."

    Cynthia, Akwa Ibom State University .
  • "Sorry, it was in my spam folder all along, I should have looked it up properly first. Please keep up the good work, your team is quite commited. Am grateful...I will certainly refer my friends too."

    Elizabeth, Obafemi Awolowo University
  • "Am happy the defense went well, thanks to your articles. I may not be able to express how grateful I am for all your assistance, but on my honour, I owe you guys a good number of referrals. Thank you once again."

    Ali Olanrewaju, Lagos State University.
  • "My Dear Researchwap, initially I never believed one can actually do honest business transactions with Nigerians online until i stumbled into your website. You have broken a new legacy of record as far as am concerned. Keep up the good work!"

    Willie Ekereobong, University of Port Harcourt.
  • "WOW, SO IT'S TRUE??!! I can't believe I got this quality work for just 3k...I thought it was scam ooo. I wouldn't mind if it goes for over 5k, its worth it. Thank you!"

    Theressa, Igbinedion University.
  • "I did not see my project topic on your website so I decided to call your customer care number, the attention I got was epic! I got help from the beginning to the end of my project in just 3 days, they even taught me how to defend my project and I got a 'B' at the end. Thank you so much researchwap.com, infact, I owe my graduating well today to you guys...."

    Joseph, Abia state Polytechnic.
  • "My friend told me about ResearchWap website, I doubted her until I saw her receive her full project in less than 15 miniutes, I tried mine too and got it same, right now, am telling everyone in my school about researchwap.com, no one has to suffer any more writing their project. Thank you for making life easy for me and my fellow students... Keep up the good work"

    Christiana, Landmark University .
  • "I wish I knew you guys when I wrote my first degree project, it took so much time and effort then. Now, with just a click of a button, I got my complete project in less than 15 minutes. You guys are too amazing!."

    Musa, Federal University of Technology Minna
  • "I was scared at first when I saw your website but I decided to risk my last 3k and surprisingly I got my complete project in my email box instantly. This is so nice!!!."

    Ali Obafemi, Ibrahim Badamasi Babangida University, Niger State.
  • To contribute to our success story, send us a feedback or please kindly call 2348037664978.
    Then your comment and contact will be published here also with your consent.

    Thank you for choosing researchwap.com.