Quality Control Laboratories
Batch plants equipped with the state of arts laboratories to control and monitor the quality of raw materials as well as the design of concrete admixtures in order to ensure that the concrete is exceeding the required specifications.
Dar CONCRETE is committed to provide the highest quality levels to our customers, Our batch plants are well equipped with Quality Control laboratories that have the latest testing equipment to conduct quality tests on fresh and Hardened concrete as well as acceptance and rejection tests on raw materials, including cement and aggregates with highest accuracy and consistency standards.
The accurate control in the production process is consistent with the quality control management system that we have in our batch plants. As the overall quality control system in batch plants aim to identify and correct most of the errors before the delivery of concrete to sites.
DAR CONCRETE is committed to perform periodic calibration of equipment and scales used in the production of concrete and tests are conducted according to the special calibration schedules in order to verify the stability of quality in batch plants and tests are in conformity with the standard specifications.
DAR CONCRETE quality assurance program is applied to verify that the concrete produced is in conformity with the highest quality standards and there is a consistency of performance of the concrete mix, Aside from the date of production or delivery site.
DAR CONCRETE produce and sell concrete in accordance with the quality standards specification and technical requirements of clients. Our goal is to build a strong and extensive relationships with our customers and to maximize the benefit and profitability for all parties in the long term. Therefore, the Company is:
- Selecting carefully the raw materials through conducting the necessary tests for each concrete component to confirm the quality and conformity with the standard specifications and its suitability for use in concrete mixtures in order to achieve the highest levels of quality and durability of the design mix and the meet the requirements of the customer.
- The concrete mix is designed accurately in accordance with the required specifications by the client or consultant and concrete test are performed to achieve the optimal performance.
- The company is committed to using the control program in f the central mixers by the computer to achieve the highest levels of accuracy in the concrete mix through controlling the content of aggregates, cement, additives time of mixing.
Quality control laboratories include the equipment hereunder:
- Automatic Compression Testing Machine 2000 KN ELE.
- Standard ASTM sieves.
- Drying Oven.
- Air Entrained pressure meter.
- Precision balances.
- Cube molds 15*15*15 cm for concrete test.
- Cube molds 5*5*5 cm for cement test.
- Slump cone set.
- Curing tanks.
- Flakiness and Elongation index Gauge.
- Unit weight measure 10 lit.
- Digital Thermometers
- Lab Mixers.
Raw materials used in concrete production:
- DAR CONCRETE choose the best raw material used in the concrete production delivered from an accredited local authorities and international companies.
- The company's quality assurance team ensure the source of material such as quarries, crushers, factories, and ensure to get the manufacturing test certificates.
- According to the quality control plan, Quality Assurance team perform a visual examination and to revise the received invoices, as well as samples and for each raw material received in batch plants.
- The usual tests are conducted on all materials that are received.
- Aggregates are stored in appropriate containers, according to their sizes.
- Cement is stored in water proof silos, according to the cement type.
- Additives are stored in water proof containers according to its type. And these containers are supplied by the additives supplier in accordance with the standard specifications of these materials.
- Ground water tank is completely isolated and other tank made of iron provided with the cooling unit to keep the water temperature at the desired degree of mixing.
The Timing for Calibration Tests:
No. |
Test |
Dar Concrete |
External |
Frequency |
Frequency |
||
1 |
Batching Plant Calibration |
Once a month |
Once a year |
2 |
Crushing Machine Calibration |
NA |
Once a year |
Material Tests Schedule Aggregate |
|||
1 |
Sieve analysis of fine and coarse aggregate |
Twice a week |
Once in three months |
2 |
Materials finer than sieve no. 200 |
Twice a week |
Once in three months |
3 |
Specific gravity of fine and coarse aggregate. |
Once a week |
Once in three months |
4 |
Absorption of fine and coarse aggregate. |
Once a week |
Once in three months |
5 |
Unit weight of fine and coarse aggregate. |
Once a week |
Once in three months |
6 |
Resistance to abrasion of coarse aggregate by use of Los Angeles machine |
NA |
Once in three months |
7 |
Clay lumps and friable particles in aggregate |
NA |
Once in three months |
8 |
Soundness of aggregate by use of sodium or magnesium sulphate |
NA |
Once in three months |
9 |
Sulphate content |
NA |
Once in three months |
10 |
Chloride content |
NA |
Once in three months |
Cement |
|
|||||
|
|
|||||
Compressive strength of Hydraulic cement |
NA |
Once in three months |
||||
Fineness of Portland cement |
NA |
Once in three months |
||||
Autoclave expansion of Portland cement ( Soundness ) |
NA |
Once in three months |
||||
Time of setting of hydraulic cement |
NA |
Once in three months |
|
|||
The Timing for Calibration Tests:
No. |
Test |
Dar Concrete |
External |
Frequency |
Frequency |
||
1 |
Batching Plant Calibration |
Once a month |
Once a year |
2 |
Crushing Machine Calibration |
NA |
Once a year |