Skyscrapers are beautiful landmarks that shift the skyline of every city to different direction. Developers go big distances to build one. It needs really detailed planning and years of preparation before you can even start. One of the biggest problems is how to get concrete everywhere it needs to be. Let's have a look at boom concrete pump (boom) which does this incredibly difficult job with finesse.
Booms play an irreplaceable role in building huge structures. Whether we talk about football stadiums, multi-storey car parks or skyscrapers, booms are used from the early start of the construction almost till its end.
Their first use is pouring the concrete into mat slab foundation of a structure. I am not sure how Ancient civilizations did it without bumps but they are nowadays here to help us greatly. Pumping needs great preparations beforehand. Everything needs to be on its place. The most important is formwork. Another use is to pump the concrete into multiple storeys above ground.
When building this type of a huge structure, as skyscraper definitely is, developers need high quality formwork and they need loads of it. They need formwork suitable for columns and storeys – metal beam slab, modular slab, flying formwork etc.
Next thing is that they need to reach the bedrock and fix the foundation to it. This is one of the most difficult jobs. Skyscrapers need to be fixed really well because they weigh thousands of tons and are sometimes situated in seismic zones where the possibility of an earthquake is quite high. Groundwater causes serious trouble and it needs to be dealt with it drastically. Developers can´t proceed any further unless all the groundwater is away. They dig trenches around the foundation and try to clog any holes with bentonite (clay).
The volume of ready mixed concrete also plays an important role. Foundation construction of Wilshire Grand (Los Angeles, the USA) is one example of great amount of concrete needed for the mat slab foundation. Pouring took unbelievable 26 straight hours and 2,120 trucks delivered 21,200 cubic yards of ready mix concrete that was poured into formwork.
There are multiple concrete pumping systems, sizes and manufacturers. One of the most famous brands used at constructions is Putzmeister and they manufacture piston or peristaltic pumps widely used in the construction industry. Piston pumps use systems based on valves (trunk or “S” type).
Peristaltic pumps operate with lower pressure (up to 30 bar) and are fully dependable on their suction performance whereas piston pumps work with quite high pressure and therefore are able to get the concrete to great heights. First mentioned are used for pouring concrete mostly into foundation – spraying it on mat slabs.
Piston pumps, using high pressure and hose systems of very thin diameter (125-150mm), move big volumes of concrete into great heights in short time. The boom operators have to make sure that the concrete flow rate doesn't drop. And it is very important to keep the whole system clean after the delivery because if the concrete starts to settle or cure it can damage the pistons or the delivery line.