Concrete is a unique construction material whereby it can be mixed at a central batching plant and subsequently transported and placed at the final required on-site location which may be a considerable distance away. Concrete utilised in hot weather conditions, such as Brunei Darussalam, require additional consideration due to the higher surrounding temperature. A study was done to investigate the effects of different mixing times using different mixing methods on concrete exposed to hot weather conditions. Concrete consistence, or workability, was found to be reducing with respect to time, regardless of mixing method, and incorporation of superplasticisers. Continuous Mixing led to slightly lower slump loss as compared to Intermittent Mixing of the concrete. Maximum concrete compressive strengths were found at different optimal times of mixing, and is dependent on the concrete components and additions utilised. Subsequent to these optimal times, the compressive strengths gradually decreased. In addition, for mixes incorporating superplasticisers, prior to the maximum compressive strengths at the optimal times, there was a reduction in the compressive strengths. Continuous Mixing yielded higher compressive strengths than Intermittent Mixing, although the differences were minor. The differences were even less when superplasticisers were utilised.

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