Envocrete Limited

Geopolymer Concrete We are pleased with the rheological properties, pot life, and setting characteristics of our Geopolymer mix at room temperature. Our system is user-friendly, with minimal alkalinity, and offers an 80% reduction in CO2 emissions compared to conventional Portland cement-based concrete. Geopolymer concrete offers several significant advantages over traditional concrete: High Durability: Geopolymer concrete is highly resistant to chemical attacks, including sulfuric acid, chlorides, and other aggressive substances. This makes it ideal for use in harsh environments such as wastewater treatment plants, marine structures, and industrial facilities. Heat Resistance: Geopolymer concrete demonstrates exceptional fire and heat resistance. It can withstand temperatures up to 800°C without significant degradation, making it suitable for fire-prone environments or buildings requiring high thermal resistance. Lower Shrinkage: Geopolymer concrete typically experiences lower shrinkage compared to traditional concrete, reducing the risk of cracking as it cures and dries. Interested in exploring Geopolymer concrete in New Zealand? Contact us today! Follow Envocrete for more updates!

In case you are interested and missed the live session last week. You can watch the video here. Thanks to the Society of Floating Solutions for hosting this event.

Please join if you are interested. It will be tomorrow, 17th October, at 4 pm SGT.

Check out the reflection of our unpolished UHPC mix with 80% slag (GGBS) replacement and 2% recycled fibre. It’s 20% lighter than conventional UHPC while achieving superior performance. Can it get any better? Follow Envocrete for more!

We are thrilled to announce that our LinkedIn community has reached 2,000 followers! Thank you for being an essential part of our journey—your support inspires us every day. We look forward to sharing more exciting insights and innovative projects with you in the future! Let’s bring back the environment to concrete with Envocrete.

A great event on the durability of floating concrete platforms by the Society of Floating Solutions Singapore (SFSS). Please follow the link to register!

Building Noah’s Ark: A 6400 Sqm Concrete Dry Dock We had a tremendous experience as part of the team that designed and built a 6400 sqm floating concrete dry dock (138 x 46 meters) for Marisco Limited. This platform is constructed with Grade 100 MPa self-leveling concrete (cube strength) and is capable of lifting ships up to 9500 tons and 180 meters in length for repairs. It is designed to support 200 tons/sqm along the centerline and 100 tons/sqm at other points. The platform can withstand wave loads of up to 10 meters and endure harsh marine environments, thanks to its low water/binder ratio (0.25) and the inclusion of undensified silica fume and Ground Granulated Blast Furnace Slag (GGBS). The use of precast concrete and a half-slab deck system was crucial in achieving a construction timeline of less than a year. While we were building this in Batam, Indonesia, many referred to it as Noah’s Ark, doubting our ability to lift it off the ground and launch it into the water due to its sheer weight of 15,000 tons. The team consisted of several key partners, including Yee Precast Design Group Ltd, GL Engineering & Construction Pte Ltd, BMT, PT Freyssinet Total Technology, PERI Formwork Scaffolding Engineering (Pty) Ltd, ECON PRECAST SYSTEM PVT. LTD., and several other companies. The platform was successfully launched on May 1, 2017, and has been serving the client ever since. Concrete is a preferred construction material for stationary floating structures in various applications, including floating ports, event centres, hotels, stadiums, energy islands, floating wind turbines, and drilling stations. If you have an exciting opportunity for collaboration, please reach out to us at Envocrete Limited.

Grade 100 MPa (14,500 psi) cube strength was used for these shell cylindrical structures, which have a height of 3.3 meters (10 feet) and a diameter of 3.3 meters (10 feet), with a wall thickness of 100 mm (4 inches). The cylinders act as columns carrying significant loads. The mix contains 10% undersified silica fume and 30% GGBS, with a water/binder ratio of 0.25. Using a central spreader cone and eight external vibrators, we successfully cast these double-layer reinforced cylinders with minimal difficulty. The design slump was 650 ± 50 mm, and the mix was very cohesive, preventing segregation when falling from a height of 3 meters under heavy external vibration. The great challenges bring great satisfaction. Follow Evnovrete for more!

Part 2: Mass Concreting with Grades 40, 85, and 105 MPa (Lessons Learned) The first picture shows Grade 85 MPa concrete after demoulding. The project involved mass concreting of cylindrical precast structures with diameters of 3.1 meters and heights of 2 meters (for Grade 40 MPa) and 1.4 meters (for Grades 85 and 105 MPa). The temperature at the start of casting was 32°C. For Grade 85 and 105 MPa, ice jackets were used during the first few hours. For Grade 40 MPa, the maximum temperature was 75.8°C, with a temperature differential of 18.5°C. For Grade 85 MPa, the maximum temperature was 77.3°C, with a core temperature differential of 14.8°C. For Grade 105 MPa, the maximum temperature was 72.3°C, with a core temperature differential of 15.4°C. Picture 2 shows the location of the thermocouple sensors in the Grade 85 MPa concrete. Pictures 3, 4, and 5 illustrate the temperature profile, the differential temperature to the surface, and the differential temperature to the side for Grade 85 MPa, respectively. The total cementitious content for Grades 85 and 105 MPa was identical. However, a lower water-to-binder ratio and a higher dosage of PCE admixture were used to achieve Grade 105 MPa. The average strength at 28 days for Grades 40, 85, and 105 MPa was 54.5 MPa, 90.5 MPa, and 104.5 MPa, respectively. The lower peak temperature for Grade 105 MPa may be attributed to the increased retardation effect of the PCE admixture at higher dosages and the extended use of ice jacketing.

Part 1: Mass Concreting with Grades 40, 85, and 105 MPa (Lessons Learned) This video showcases the casting of Grade 85 MPa concrete. We had the opportunity to lead a project involving mass concreting of cylindrical precast structures with diameters of 3.1 meters and heights of 2 meters (for Grade 40 MPa) and 1.4 meters (for Grades 85 and 105 MPa). Due to the use of a self-leveling mix, we were unable to employ our usual layering techniques for mass concreting. Instead, we implemented several measures: sheltering, casting at night, ice jacketing, insulation, and high GGBS (Ground Granulated Blast Furnace Slag) replacement. Notably, no silica fume was used in this project. Our objective was to maintain the temperature differential at 20°C and ensure a peak temperature of less than 80°C. Maintaining a peak temperature in the range of 75°C to 85°C is common for high GGBS replacements, with minimal risk of ettringite formation. We observed very interesting results, particularly when comparing Grade 85 MPa with Grade 105 MPa, which we will share in the next post along with temperature profiles from this project. Data on mass concreting of Grade 105 MPa concrete is limited. Stay tuned and follow Envocrete for more updates!