Many startups are cash-poor which makes finding the money to pay for a place on an incubator program a problem, which is why handing over equity is more common. Would you still be able to meet your growth goals if you sought advice from other means, which would allow you to maintain control of your equity — for example from a mentor or consultant?
But what are accelerators and incubators, and is either right to help you grow your startup? Startup Incubators An incubator normally supports new ventures during the ideas stage.
Startup Accelerators As the name suggests, accelerators help startups to accelerate their growth. What are the Pros and Cons of Accelerators and Incubators? Access to investment — either directly as part of an accelerator program, or by introducing you to a network of potential investors. Weaknesses Highly over-subscribed — few startups make it into accelerator or incubator programs.
Mixed quality — these days it seems like accelerators are popping up on every corner. Accelerating admixtures can be used to increase either the rate of stiffening or setting of the concrete or the rate of hardening and early strength gain to allow earlier formwork striking and demoulding. Most accelerators achieve one rather than both of these functions.
Hardening accelerators are most effective at low temperature. Accelerators can be used with superplasticisers where early age strength is required, especially at lower temperatures. In the UK the prime use of set accelerators is to control the setting time of floor slabs in cold weather as extended setting time delays finishing and power-trowelling. They are also used to reduce the risk of damage to concrete by freezing when concreting in cold weather and to allow the earlier removal of formwork.
Combinations of different accelerators can be used. Tests should be conducted to determine which combinations work best with the materials being used.
Photo credit Trinic. Accelerators can also pose challenges for precasters, such as long-term strength gain and shrinkage. These are easily dealt with as long as the precaster is aware of the challenge and the solution. Osborne said many admixture producers also include components that help offset shrinkage, which is a concern for precasters. Expansive agents and surface tension-reducing components can be included in accelerators. ASTM C dictates the maximum allowable amount of shrinkage and water reduction caused by the use of accelerating admixtures.
Precasters should also be aware of how much time will elapse between mixing and placing the concrete, how the concrete will be transported to the forms, ambient temperature and the mix water temperature. Some precasters use hot water to increase the rate at which the hydration reactions occur. In some cases, if approximately 30 minutes will elapse between mixing and casting, a set accelerator could make the concrete too stiff to place.
Combinations of different accelerators mixed in manufacturer-specified ratios could also be used, depending on job specifications and how all the raw materials and chemicals interact. It is important to test different products in test batches to determine which combinations work best with the materials being used.
According to Mark Celebuski, partner at Trinic, a manufacturer supplying powdered accelerating admixtures, precasters often use accelerators to offset the delaying effects of other additives. Some common additives like water-reducing admixtures or supplementary cementitious materials can decelerate the set of concrete. Using accelerators helps hydration occur at an elevated rate and increases the rate of set and strength gain. Precasters can also use accelerators to turn forms faster, which translates into greater efficiency and a reduction in total days and labor costs for production.
Thank you for your interest! Hi sara , i am a precast slab producer , glad to meet you, can you suggest me a formulation for an accelerator to minimization final setting time of concrete. Thank you for your comment, Hassan.
If you have any other questions, please contact us at Hi Sara Can you tell me how chlorides are accelerating the setting of cement? Calcium chloride salts will catalyze the hydration of the calcium silicates dicalcium silicate Ca2SiO4 and tricalcium silicate Ca3SiO5.
It does this by weakening the barrier or initial hydration products that may form on the cement surface as it comes into contact with water. Your email address will not be published. Save my name, email, and website in this browser for the next time I comment. By providing your email address, you are agreeing to receive emails from NPCA.
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