August 03, 2024

August 01, 2024

June 13, 2022

- Building Construction (75)
- Building Materials (73)
- Columns (2)
- Concrete Beam (3)
- Concrete Construction Techniques (4)
- Concrete Mix Design (9)
- Concrete Repair (11)
- Concrete Slab (10)
- Construction Equipment (14)
- Construction News (7)
- Design of Structures (14)
- Engineering Drawing (1)
- Estimation (2)
- Geotechnical engineering (25)
- Highway Engineering (11)
- Innovations (27)
- Material Testing (8)
- Matrix Analysis of Structures (2)
- Mechanical Engineering (3)
- Transportation Engineering (9)

- September 20234
- August 20231
- July 202312
- June 202310
- May 202311
- April 202310
- March 202318
- February 20234
- January 20238
- December 20229
- November 20229
- October 202212
- August 202217
- July 202211
- June 202215
- May 20221
- April 202213
- March 202215
- February 202214
- January 202223
- December 20216
- November 20212
- October 20217
- September 20215
- August 202118
- July 202122
- June 202115
- May 20216
- April 202110
- March 202111
- February 202132
- January 202123
- December 202011
- November 20203
- September 202019
- August 202012
- July 20204
- June 202010
- May 202012
- April 202010
- March 20206
- February 20203
- November 20192
- October 20194
- September 20193
- August 201915
- July 20199
- June 20191
- May 20193
- April 20192
- March 20193
- February 20195
- October 20182
- August 20182
- June 20183
- April 20187
- March 201813
- February 20189
- January 20184
- December 20171
- October 20172
- September 201711
- August 20176
- July 201713
- June 20177
- May 20176
- April 20171
- March 20172
- January 20171

Anonymous
June 07, 2017

The concrete compressive strength test result of cubes from a random sampling of a mix although exhibit variations, when they are plotted on a histogram are found to follow a bell-shaped curve, which is termed as the Normal or Gaussian Distribution Curve.

The results are said to follow a normal distribution as shown in the figure-1, given that they are equally placed above the mean value. The normal distribution curve can be used to ascertain the variation of concrete strength from the mean. The area beneath the curve shows the total number of test results.

The proportion of results less than the specified value is represented by the area under the curve to the left – hand side of the vertical line drawn through the specified value.

A normal distribution curve can be defined by two parameters, namely the mean strength and the standard deviation.

Fig.2 |

The figure-2 shows the frequency density versus compressive strength distribution curves of concrete mixes A and B. The curves are symmetrical about the mean value. The Mix B Indicates better quality control than that is obtained from the Mix A, even though both the mixes have the same average strength.

The measure of Variability of Concrete Strength

The terms and the parameters required for the measurement of the variability is mentioned one by one

It is defined as the arithmetic mean of the set of actual test results. The average or the mean x for a set of ‘n’ observation x_{1}, x_{2}, ……x_{n }is expressed as,

It is defined as the difference between the largest and the smallest value from the set of observations.

The root mean square (rms) deviation of the consignment from the mean x is termed as the standard deviation and is defined numerically as

The square of standard deviation is called as the variance, i.e. Variance,

The standard variation increases with the increase in the variability.

March 02, 2022

January 19, 2022

March 22, 2024

July 17, 2021

July 02, 2020

August 11, 2021

September 10, 2017

March 02, 2022

Created By SoraTemplates | Distributed By Gooyaabi Templates

Close Menu

## 0 Comments

Commenting Spam Links Are Against Policies