| We are increasingly seeing the effects of building | | | | The floor surface can be made of concrete or steel. |
| collapse due to earthquakes in regions such as Haiti | | | | International Casino Car Park, Chiromo road |
| and collapse due to poor workmanship such as the | | | | roundabout. |
| recent building collapses in Kiambu. With rapid | | | | A good example of this in Kenya is the Car Pak at |
| urbanization, more high-rise buildings are coming up in | | | | the International Casino hotel next to the Chiromo |
| major towns creating perfect recipes for disaster as | | | | road roundabout near Westlands. |
| people get trapped underneath tons and tons of | | | | This car park has a concrete surface suspended and |
| concrete in case the building unfortunately collapses | | | | supported by steel I beams and columns as shown |
| -either due to an earthquake or poor workmanship. | | | | below. |
| There are solutions to avoid this kind of disaster by | | | | The car park is very strong-it has supported the |
| having flexible steel grid supported buildings with | | | | weight of cars for very man years and it has not a |
| light-weight sandwich panel wall infill. | | | | slight sign of failure. |
| Several major towns in Kenya such as Nakuru sit | | | | This means that if used to support a building where |
| right in the middle of the Rift Valley which is a | | | | the loading is mainly human and furniture e.g. offices |
| seismically unstable region and earthquakes are not | | | | and residential buildings, the PEB system will work |
| known to give notice before they strike. | | | | excellently since if it can support the heavy load of |
| Measures should be taken to ensure that there are | | | | cars, then it can support the light load of humans and |
| mechanisms in place to give early warning to avoid | | | | furniture. |
| disasters. Countries that are prone to earthquakes | | | | Earthquake Loading design. |
| such as Japan have an average of 40% of new | | | | The structural design of the PEB will depend on the |
| high-rise buildings coming up in Steel structural | | | | Live loads, Earthquake, collateral and wind loads that |
| frames-one of the world's highest-this is partly dues | | | | are specified by the consultant structural engineer in |
| to steel's ability to resist the impact of severe | | | | conjunction with the relevant Local Authority Building |
| earthquakes. Past earthquakes in USA [San | | | | approval department. |
| Francisco-1906, Long Beach-1933, and Japan [Kanto | | | | PEB subsystems |
| -1923] during the first part of this century gave | | | | The main building structure comprises of 2 |
| engineers confidence in steel as a reliable material for | | | | subsystems:-[1]a rigid steel frame including columns, |
| earthquake resistant design. During these events, | | | | rafters, beams and purlins and [2] wall and roof |
| there were typically fewer problems observed in | | | | panels. |
| steel structures as compared with concrete and | | | | The roof and walls are made of Sandwich panels. |
| masonry buildings of similar size and scale. | | | | Sandwich panels comprise of an exterior metal skin, a |
| PEB system of construction is based on the U.S.A | | | | polyurethane interior core and an interior flat skin |
| Building code. PEB system originated from U.S.A which | | | | made of metal. The core thickness is available in 35, |
| produces over 1 million PEB Structures per year. | | | | 50, 75 and 100mm.The density of the polyurethane is |
| In Kenya, we mainly rely on the British Building code | | | | 35-40Kg/m3. |
| and standards for construction. The British Standard | | | | Design Code. |
| is mainly Reinforced -Concrete based as in most | | | | The design code used is in accordance with the Steel |
| structures such as columns and beams are designed | | | | Construction Manual published by the American |
| to be concrete-based with twisted steel | | | | Institute of Steel Construction [AISC]. |
| reinforcement of between 8 mm to 20mm thickness | | | | All welding is done in accordance with the Structural |
| in the inside. This is the type of building construction | | | | Welding Code-Steel D1.1 of the American Welding |
| that you will see every day in Kenya and East Africa | | | | Society[AWS]. |
| in general. | | | | PEBs are designed using guidelines published by Metal |
| The PEB system replaces the concrete columns and | | | | Building Manufacturers Association of U.S.A which is a |
| beams with I Section steel beams and columns. With | | | | world-recognized authority on pre-engineered steel |
| the rapidly increasing price of cement for making the | | | | buildings and its guidelines are accepted as standard |
| concrete, this design is certainly more cost-effective. | | | | practice in his industry. |