### Present Remotely

Send the link below via email or IM

• Invited audience members will follow you as you navigate and present
• People invited to a presentation do not need a Prezi account
• This link expires 10 minutes after you close the presentation

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.

# Concrete Propeties from

No description
by

## Zhongkai Hu

on 17 October 2013

Report abuse

#### Transcript of Concrete Propeties from

Concrete Properties from
Non-Destructive Test

Non-Destructive Tests
OUR PLAN
AIM
Thinking
Rebound
Hammer Test
Ultrasonic Pulse Velocity Test
Resonant Frequency Test
Step 1
Step2
Determine the uniformity of blocks by
Rebound Hammer Test
Step 3
Determine compressive strength of blocks by UPV test
Group 10
Zhongkai Hu
Sisi Du
Dan Wang
Hao Chen
Yaodong Li
Zheng Wang

What is Rebound Hammer Test?
Principles
1.Check
Uniformity
2.Determine the time for removal of formwork
3.
Time saving
, easy to record data
4.Economical
Limitation
1. Sensitive to Local Variarion
2. The angle between the hammer and the suface
3. Moisture Content
4. Temperature
Data and Calculation
What is Ultrasonic Pulse Velosity Test
The test procedure is measuring the time taken for an ultrasonic pulse to travel though a known length of concrete, from the results we can therefore calculate the Velocity by using formula
V=L/T.

The
velocity
of the longitudinal ultrasonic pulse is related to the
elastic properties of the concrete
and
compressive strength
Limitation
1.Constituent materials
2. Moisture Condition
Data and Calculation
What is Resonant Frequency Test?
principle
Resonant frequency
Dynamic Elastic Modulus
Compressive Strength
Limitations
Laboratory test on
prepared specimens
Therefore, we cannot ues this method for real structure
Data from Experiment
Estimate the likely
deformation
if a vertical compressive load of
1.5MN
is applied uniformly to the top face of each of blocks
Deformation
Young's Modulus
E
is unknown, solve for
E
?
Find E by NDT
Ultrasonic Pulse Velocity Test
Velocity
Dynamic elastic Modulus
Poisson's Ratio
Resonant Frequency Test
Dynamic elastic Modulus
Resonant
Frequency
Length
Density
HOWEVER..
Resonant frequency test can only be used for
prepared
specimens
As a result....
Elastic Modulus
Compressive
Strength
Find
k
from resonant frequency test
Determine Dynamic elastic Modulus
For Mix 1:
From the Data, n=
4609
Hz, l=
0.5
m, ρ=
2407.
4kg/m^3.
Ed=4*(
4609
Hz) 2(
0.5
m)^ 2 (
2407.4
kg/m^3)=
51140.11
Mpa

Determine Static Elastic Modulus
The ratio of static to dynamic modulus is normally between
0.8
and
0.85
Es=
0.83
Ed
Determine the Compressive Strength
During the lab, we crushed the cubes and got compressive strength
(Resonant frequency test)
Determine K accoding to lab records
k
=4.97
MIX A
MIX B
Calculate deformation
separately
1. Determine the Velocity
2.Compressive Strength
As the ultrasonic pulse velocity can be correlated empirically with strength, the further measurement for block B,C can be used to determine the compressive strength from the graph above.
Step 4
Calculations
Compressive Strength of each Mix
UPV TEST
Elastic Modulus
Deformation of each Mix
Total Deformation
Sum up
Thanks for listening !
Questions?
TEAM 10
1. contacting surface
2.direct set-up
3. Calibration
Full transcript