Welcome to AMIE Study - AMIE India Students Forum

AMIE Study - AMIE India Students Forum

collapse collapse

* Shoutbox

Refresh History
  • devjangde: Dear Sir/Madam please me out for my membership Number and  reference number.  I lost both of this . Is there any way to find out?
    October 08, 2018, 09:32:50 AM
  • devjangde: Dear Sir/Madam,
    October 08, 2018, 09:30:46 AM
  • Srijib: Can someone have any notes for the subject society and environment
    October 07, 2018, 07:37:52 PM
  • muleredd: can someone have previous year question papers for Sec B Mining Engineering ?
    October 07, 2018, 01:52:05 PM
  • Pahadi57: Will I send the printed copy of the winter application form after online form filling successfully.... Pls advice
    October 05, 2018, 05:54:03 PM
  • SANUKARMAKAR1: Section A society and environment and computing and informatics not required .
    October 04, 2018, 03:19:43 PM
  • pravendrapmmb: Where to get books for section B Electrical Engineering
    October 02, 2018, 10:23:23 PM
  • rodricksarthur: Sum 2018 results, Mining Engineering Sec B, MN435 result is not declared. Any one of you, know why?
    September 28, 2018, 08:59:53 AM
  • divakara.sd: Dear sir/Madam I am Divakar, Study under IEI in M and M branch. Recently I am registered for section B I quired the study notes and Questions papares for fallowing subject.  IC402- ENGINEERING MANAGEMENT MM403- METALLURGICAL THERMODYANAMIC AND KENETICS MM404-EXTRACTIVE METALLURGY MM405-MECHANICAL BEHAVIOUR OF MATERIALS MM406-PHYSICAL METALLURGY MM407-METALLURGICAL DESIGN MM432-WELDING AND ALLIED PROCESS MM433-ADVANCED PHYSICAL METALLURGY MM434-FOUNDRY ENGINEERING   Thanks and regards Mr.Divakar State-Karnataka District-Bellary Place-Emmiganure Pin code-538113 Phone number-9743956204
    September 24, 2018, 11:48:09 PM
  • Anu Mangalore: Section b mechanical notes required
    September 21, 2018, 09:37:37 PM
  • AjeetIOCL: can u tell me ,my AMIE registration is of 2010 which has expired in 2016 ,I have Re-registered again in 2018 by re-registration process .is my date of election will be changed or remain same.is this degree of AMIE will be Valid? because Supreme Court has decided not to consider AMIE degree after May 2013
    September 20, 2018, 08:59:06 PM
  • jooly: is data structure in CS is tough?do we need to learn C program thouroughly for it?
    September 11, 2018, 09:33:03 AM
  • Manish100ni: I got AAAD grade in section A , i am pass or fail ??
    August 19, 2018, 05:02:34 AM
  • [email protected]: Can anyone tell if Saudi Engineers Council accept  AMiE or not?
    July 18, 2018, 11:38:24 AM
  • Khadeejath Shamna: Can we send section b registration form and examination form together?  When can we register for section b winter exam 2018?
    July 09, 2018, 03:46:15 PM
  • GCPATIL: How to change mobile number and email address
    July 09, 2018, 01:33:10 AM
  • Sanoj.kaushik: Hi everyone, It is informed that civil lab experiments at Manav Rachna Institute would be started in mid july. So, kindly informed to other friends.
    June 15, 2018, 05:33:15 PM
  • ramajit: yes. i also need help for project work. any format or ref available. pls send me email [email protected]
    June 12, 2018, 10:22:21 AM
  • JYOTI VERMA: mail me on [email protected]
    June 10, 2018, 09:33:12 PM
  • JYOTI VERMA: i wqnt to know about mechanical project work topiics.please send me it on my mail if any one have
    June 10, 2018, 09:32:34 PM

* Search


* User Info

 
 
Welcome, Guest. Please login or register.
Did you miss your activation email?

* Board Stats

  • stats Total Members: 48702
  • stats Total Posts: 27337
  • stats Total Topics: 6606
  • stats Total Categories: 6
  • stats Total Boards: 31
  • stats Most Online: 626

Author Topic: notes on concrete  (Read 1393 times)

Description:
September 22, 2011, 12:42:33 PM
  • Super Member
  • Registered User
  • *
  • Posts: 36
    • View Profile
Advertisement
Consolidation Of Concrete

The term consolidation of concrete is used to mean the compaction between aggregate and aggregate; between aggregate and reinforcement; and between aggregate and forms.
The main aim of consolidation of concrete is to eliminate air bubbles and thus to give maximum density to the concrete. An intimate contact between concrete and reinforcement is ensured by proper consolidation.
The difference between voids and pores may be noted. The voids are the gaps between two individual particles. The pores represent the opening within the individual particles. The process of consolidation of concrete can be carried out either with hand or with the help of vibrators.
Hand consolidation: For unimportant works, the consolidation of concrete is carried out by hand methods which include ramming, tamping, spading and slicing with suitable tools.
The hand methods require use of a fairly wet concrete. It should however be remembered that wherever feasible, the hand compaction should be preferred because the use of vibrator my lead to the segregation of the aggregates. As a matter of fact, the concrete mixes which can be hand-compacted should not be compacted by the use of vibrators.
Vibrators: These are the mechanical devices which are used to compact concrete in the formwork. The advantages of vibrators over hand methods are as follows:

(1) It is possible by means of vibrators to make a harsh and stiff concrete mix, with a slump of about 40 mm or less, workable.

(2) The quality of concrete can be improved by use of vibrators as less water will be required or in other way, economy can be achieved by adopting a leaner mix when vibrators are used.

(3) The use of vibrators results in the reduction of consolidation time. Hence the vibrators are used where the rapid progress of work is of great importance.



The poker vibrates while it is being inserted. The internal vibrators should be inserted and withdrawn slowly and they should be operated continuously while they are being withdrawn. Otherwise holes will be formed inside the concrete. The vibrator can be placed vertically or at a slight inclination not exceeding 100 to the vertical with the view to avoid flow of concrete due to vibration int

These vibrators require more power because of loss of some power in vibrating the rigid shutters. They are also heavy and hence they cannot be clamped at as many points as possible for uniform compaction of concrete. The compaction by these vibrators is found to be effective only upto a distance of about 450 mm from the face of the formwork.

(4) Vibrating tables: These are in the form of a rigidly built steel platform mounted on flexible springs and they are found to be very electromagnetic action or electric motors. They are found to be very effective in compacting stiff and harsh concrete mixes and hence they are invariably used in the preparation of precast structural products in factories and test specimens in laboratories.
The tables are vibrated either mechanically or by placing the springs under the supports of tables. The frequency of vibration varies from 3000 to 7200 vibration per minute. The two parameters of vibrations are frequency and time and they are related as follows:
« Last Edit: January 01, 1970, 04:00:00 AM by Guest »


Prayrona
Pranati Roy (Banerjee)
Jr. Civil engineer
E-mail : [email protected]
Airport
kolkata-136
 

Related Topics

  Subject / Started by Replies Last post
1 Replies
489 Views
Last post June 30, 2009, 08:25:20 PM
by praveen
0 Replies
512 Views
Last post January 22, 2010, 02:06:20 PM
by salman8506
0 Replies
523 Views
Last post June 08, 2010, 02:14:44 PM
by mvr.rana
6 Replies
1622 Views
Last post March 13, 2012, 07:08:01 PM
by sandipcg
5 Replies
2184 Views
Last post October 11, 2012, 01:34:03 PM
by mahavirbarta
1 Replies
2237 Views
Last post July 16, 2016, 09:15:04 AM
by SatishPatil
0 Replies
3124 Views
Last post February 28, 2018, 01:45:27 PM
by parthiban1189

* Search

* Subscribe to Forum

Enter your email address:

Advertisement

* Recent Posts

Re: making whatsapp group by ganesan5450
[October 12, 2018, 02:40:35 PM]


Re: making whatsapp group by AJEEBHAMSA
[October 11, 2018, 12:58:09 PM]


Re: making whatsapp group by aditya_bhushan
[October 10, 2018, 07:18:40 PM]


Re: Mining Engineering by muleredd
[October 07, 2018, 02:16:55 PM]


Solid Wood Dining Table Set by bellianawil
[October 06, 2018, 05:18:26 PM]