A high-rise building is defined as a building structure with four floors or more or one with 15 meters or more in height. Traditionally building between 75 feet and 491 feet [23m to 150m] high are recognized as high-rise buildings. At Present Ultra High Rise Buildings are being constructed with height over 300 meters. But constructing a high rise/ultra high rise neeeds detailing and precision.
Everything cannot be synchronized there are specifications that need to be evaluated for perfect synchronization. Especially, the use of concrete needs to be strategized and estimated carefully.
Discussed below are some the challenges and product segregation that ena-bles in architecting a perfect high rise building.
Concrete is an essential and main component of any construction. Main challenges when concreting at great heights:
– High -performance concrete (HPC)
– Conveying (Pumping) concrete to the required height
– Workability (Flowability) over time
High-performance concrete (HPC):
The strength of the high-performance concrete ranges from 50Mpa– 100Mpa. Requirement of HPC:
– Very low water/Cement ratio generally less than 0.3
– Considerably high cement content
– Part of cement is replaced by cementitious materials
– Use of High efficient Super-plasticizers
Challenges for Making High-Perfor-mance concrete:
– Variations in fine & coarse aggregates
– Different source of cement with varying mineralogy
– Different cementitious materials properties
– Varying climatic conditions
A robust Superplasticizers such as the Sika® ViscoCrete® technology is the aptest solution to the above challenges.
Conveying or pumping the concrete to the desired height
Because of very low water/cement ratio and high fines content, the concrete becomes very sticky, very viscous and difficult to pump. Sika® ViscoCrete® technology helps in reducing the viscosity, yield stress, giving better fresh concrete behaviour even at such a low water/ bin-der ratio so that concrete can be pumped easily to the required height.
Workability over time:
To bring the concrete from long distances or site batched concrete. The concrete should have minimum flow retention period of 2-3 hours for pumping and finishing and it should set normally. Sika® ViscoCrete® technology retention polymers help in retaining (workability) flowability for hours without any effect on the setting time of the concrete.
Technological Emancipation of Viscocrete
Sika® ViscoCrete® Admixture Technology is based on new generation PCE polymers. PCE polymers are very versatile polymers, unlike SNF polymers. PCE polymers are tailor made could be designed according to specific requirements.
– Adsorption speed
– Water reduction
– High workability
– Reduced Stickiness
– Stability / Viscosity
– Slump retention without retardation
– Less sensitive
According to above properties, polymers could be formulated to achieve desired properties. With the use of Sika® ViscoCrete® technology following properties could be well achieved:
– Better fresh concrete behavior
– Stable mix
– Less viscous & Less stickiness
– High water reduction
– Slump flow retention without retardation
– Durable concrete structure
– Better cost performance
– Sustainable concrete mix
– Easily pumpable to the desired height
The right use Product is an important element for the success of any building plan. With the right product attributes craf-ting becomes easy, especially in regards to ‘high rise building as drafting the right structure is a very complicated one. Make use of correct product segregation!
For further details:
Sika India Pvt. Ltd.
601, A Wing ,Infinity Tower, Off. Link Road, Malad (W), Mumbai- 400 064.
Ph: +91 22 40384038 Fax: +91 22 40384039