General Purpose (GP)
The following links are to PDF files:
Weekly Report
Cement Certificate (Type GP)
Golden Bay Cement's Type GP cement is a premium Portland cement which is used in commercial, industrial and residential construction in New Zealand.
Type GP is a light coloured cement which has earned a reputation for quality and consistency in New Zealand construction circles.
Type GP cement is manufactured under carefully monitored conditions at Golden Bay Cement's Portland plant, near Whangarei. In addition to being the cement normally specified for general construction, Type GP's characteristics have enabled it to be used in a variety of applications which normally call for specialised cements.
Golden Bay Cement's Portland Plant manufactures a range of cements conforming to NZS 3122:1995 and other relevant Standards.
SUPPLY
Type GP cement is available in multi-walled paper sacks from Golden Bay Cement stockists and in bulk from the company's Customer Service Centres.
SPECIFICATION
Type GP cement exceeds the minimum specifications given in NZS3122:1995. Manufacture of all Golden Bay Cement products is monitored by the company's IANZ accredited laboratories.
Type GP cement conforms to the requirements of NZS3122:1995 for use with aggreates of low alkali reactivity.
Type GP cement is manufactured by grinding Portland cement clinker and gypsum, and may contain up to 5% mineral cement extender.
APPLICATIONS
Type GP cement is ideal for use in structural concrete, mortars, renders, grouts and cement based products, and can also be used as a general binder for applications such as soil
stabilisation.
Supplementary cementitious materials:
Type GP is compatible with Flyash, Silica Fume, and Ground Granulated Blast Furnace Slag conforming to the relevant sections of NZS 3122:1995 Flyash in bulk is available from Golden Bay Cement.
Admixtures for concrete:
Type GP is compatible with concrete admixtures complying with NZS 3122:1995 In hostile environments professional advice is essential to ensure all requirements are met to produce the desired durable product.
TYPICAL PROPERTIES
Type GP is the cementtraditionally used in construction and industry. It is specified when the special properties of Low Heat of Hydration (temperature rise), High Sulfate Resistance or High Early Strength are not required.
Typical Properties
| Type GP | ||
| Specific Surface Area | m2/kg | 320 - 340 |
| Sulphate Content | % | 2.1 - 2.2 |
| Loss on Ignition | % | 2.0 - 4.0 |
| Sodium Equivalent | % | less than 0.60 |
| Components (nominal) | ||
| Portland clinker | % | 91 |
| Gypsum | % | 4 |
| Mineral Additions * | % | 5 |
| Cement Improver | CBA 1115 | - |
* Mineral additions can be Limestone, Huntly Fly-ash or a combination.
|
Typical Chemical Properties | ||||
| Units | Portland clinker | Limestone | GP cement | |
| SiO2 | % | 22.8 | 4.5 | - |
| Al2O3 | % | 4.2 | 0.5 | - |
| Fe2O3 | % | 2.3 | 0.6 | - |
| CaO | % | 64.8 | 51.8 | - |
| MgO | % | 1.0 | 0.8 | - |
| Na2O | % | 0.19 | 0.08 | - |
| K2O | % | 0.49 | 0.13 | - |
| Free lime (CaO) | % | 1.3 | - | - |
| Hypothetical Compounds | ||||
| Lime Saturation Factor | % | 97.0 | - | - |
| C3S | % | 68 | - | - |
| C2S | % | 14 | - | - |
| C3A | % | 7 | - | - |
| C4AF | % | 7 | - | - |
|
Typical Physical Properties | |||
| Units | GP cement | NZS 3122:1995 | |
|
Setting time |
|||
| Initial | min | 105 | 45 min |
| Final | hr/min | 3.00 | 10.0 max |
| Soundness | mm | 1.2 | 5.0 max |
| SO3 | % | 2.2 | 3.5 max |
| Compressive Strength (ISO-CEN mortar) | |||
| 3 days | MPa | 31.3 | - |
| 7 days | MPa | 45.0 | 25.0 min |
| 28 days | MPa | 63.2 | 40.0 min |
| Mortar Drying Shrinkage | |||
| 7 days | microstrain | 440 | - |
| 14 days | microstrain | 580 | - |
| 21 days | microstrain | 600 | - |
| 28 days | microstrain | 620 | 750 max |
|
Max Temp rise |
°C | - | - |
Concrete results based on Standard Golden Bay Cement laboratory mix using commercial aggregates, admixtures and a manufactured sand. W/C=.066
