03-02-2017, 02:30 PM
Modern low- or zero-energy warehouses have solutions to reduce energy consumption in warehouse buildings and storage processes. The chapter describes solutions dedicated to energy consumption in storage, as well as the author's own ideas for adapting other solutions to storage systems.Location of a warehouse
The approximate location of a proposed warehouse for grain storage has already been decided. However, determining your exact location is an issue for engineers. If a large warehouse is planned, it is always prudent to involve local Civil Engineers at this stage.
Several factors should be considered in selecting an appropriate site. In the first place we must study the topography of the area. It is preferable to erect the store on level ground, ideally slightly raised over the surrounding area, which is well drained and not prone to flooding. Low locations should be avoided. If it is difficult to find a level area, then the less wavy or inclined area should be selected and the site should be oriented along contour lines to minimize the amount of leveling and filling that is to be made.
So it is important to determine the characteristics of the soil: its capacity of load, resistance to the compaction and characteristics of drainage. Never build on black cotton floors, as they are weak and do not have enough capacity to support the floor, even for small stores. The warehouse and accesses to it will have to be protected from running water by an effective drainage system, and the room must be able to accommodate such a system.
To facilitate access and movement of stocks, the store should be located as close as possible to a main road. It is also important to ensure that approaches to the store will allow the vehicles easy movement and maneuverability around it. This means that, in addition to the area to be occupied by the warehouse, there should be plenty of useful space around it. Also, looking to the future, there should be sufficient space for the construction of additional warehouses and utility buildings.
In tropical countries it is very important that the long warehouse shafts are oriented east-west as close as possible. In this way, the side walls are less exposed to the sun and variations in temperature inside are minimized. If the warehouse can not be oriented to the east, some benefit can be derived from locating it in the direction of the prevailing wind. The interior can be effectively cooled by opening all doors and windows at appropriate times.
Finally, considering that the grain in the warehouse will probably be fumigated with lethal gas for humans (see Chapter 8) from time to time, it is important that the site chosen is at a safe distance from housing houses, shopping centers And other areas of work.
Standard warehouse design (for information on fumigable warehouses, see Annex 4)
All stores consist of a floor, walls, a roof and one or more entrances. However, they can vary considerably in the detailed composition and construction of these basic components; And they can include others, such as fans, windows, artificial lighting, etc. The various combinations of possible characteristics have to be considered very carefully, together with other factors relating to location, intended use, etc., when planning the construction of a warehouse.
Primary importance should be attached to ensuring that the quality of the product to be stored will not be affected by physical factors such as humidity and heat. Whenever possible and practical, the store design should incorporate features that protect its contents from rodent and bird attacks, and facilitate the use of insecticides.
The warehouse should also be easy to clean and maintain (there is no point in using components that are not easily replaceable or repairable); And it must provide good working conditions.
(I) Foundations and Floor
Unstable clay soils and areas that have been filled should be avoided whenever possible, as they involve the risk of sinking. In all cases, it is necessary to excavate to a point where the soil pressure is 150 kN / m2 or better.
The soil should be able to support the weight of the grain that will be stacked on it, and also must be impermeable to groundwater. For these reasons, the floor must consist of a reinforced concrete slab placed on a well compacted hard core, with a moisture barrier sandwiched between the two. This moisture barrier should consist of a layer of asphalt, bitumen or a polyethylene film.
The reinforced concrete slab must be made with expansion joints, to avoid cracks (which hampers storage hygiene). It should be covered with a cement cover a few centimeters thick, which becomes smooth and hardened (to prevent the formation of dust). Ideally, the concrete slab should be placed after the roof is completed: to prevent the direct sun from drying too fast, and possibly causing it to crack.
The floor level should be high enough above ground level to ensure that water does not enter the store, even after the highest rainfall that can be expected. Consideration could be given to erecting the warehouse on a raised platform about 1.2 meters above ground level to facilitate the loading and unloading of vehicles; But this alternative is expensive and can add 40% to the cost of construction.
(Ii) Walls
Most modern warehouses are built with a structure, usually of reinforced concrete. The support pillars are connected to each other by lower struts, which are fixed to the floor slab, and by the upper struts that firmly hold the frame. It is essential that all joints are secure and accurate, and that the reinforcing rods are well covered with concrete. The warehouse walls are built between the supporting pillars.
If the support posts are thicker than the walls, it is important that the additional thickness is on the exterior of the building so that the internal surfaces of the walls are smooth and free of projections. This facilitates cleaning of the store, and prevents interference with other operations as well.
The walls may be made of blocks of breeze, or of bricks of stabilized earth of 15 to 20 cm of thickness, and must be made smooth by both sides. They should be painted white, on the inside for easy detection of insect pests, and on the outside to help keep the store as fresh as possible. Alternatively, the walls may be made of a lightweight material such as asbestos cement, galvanized sheet metal or aluminum sheet. However, walls of this type are easily damaged, have poor insulating properties, and are sometimes prone to erosion.
A vapor-proof barrier must be built into the base of the walls to prevent moisture from rising and causing damage to the storage structure and contents. In addition, a strip of concrete about 1 meter wide should be placed around the outside of the store to prevent rain from eroding the base of the walls below the wet course.
(Iii) Roof
The internal pillars supporting the roof frames should be avoided because, as noted above, they may interfere with pest control and other stock management procedures. Instead, roof frames must be designed in such a way that the weight of the roof is transferred to the support columns (in framed buildings), or to the walls if the store is small.
Modern engineering techniques allow very large "free crossbar" ceilings (ie ceilings without internal support pillars) to be constructed. However, such roofs are very expensive and are rarely used in building warehouses. A steel portal frame should be used if the section should be greater than 15 meters. Warehouses below this width may have reinforced concrete roof frames.
Wooden or bamboo roof frames are only suitable for warehouses of no more than 4 or 5 meters wide. The wood used must be well dried and treated with a preservative.
The roof covering may be galvanized steel or aluminum sheet, or cement asbestos; The latter being more fragile but with better insulating properties. Tiles are not recommended, especially for large warehouses.
The roof should protrude from the pediments by 0.7 to 1.0 meters, and the eaves by at least 1 meter. This ensures that rainwater falls off the walls; And it avoids the need for gutters and drainage channels, which can be blocked or help rodents enter the warehouse. The overhang also helps keep the walls cool and protects the ventilation openings from rain.
(Iv) Ventilation
Ventilation openings are necessary to allow air renewal and reduce the temperature in the warehouse, also allow some light to enter. If these openings
Localized too low can be the source of numerous problems: entry of water, rodents, thieves, etc. These problems are avoided when fans are placed under the eaves. They should be installed outdoors with anti-bird grills (20 mm mesh) and inside (10 cm behind the racks) with 1 mm mesh (removable for cleaning) that will deter most insects.
The approximate location of a proposed warehouse for grain storage has already been decided. However, determining your exact location is an issue for engineers. If a large warehouse is planned, it is always prudent to involve local Civil Engineers at this stage.
Several factors should be considered in selecting an appropriate site. In the first place we must study the topography of the area. It is preferable to erect the store on level ground, ideally slightly raised over the surrounding area, which is well drained and not prone to flooding. Low locations should be avoided. If it is difficult to find a level area, then the less wavy or inclined area should be selected and the site should be oriented along contour lines to minimize the amount of leveling and filling that is to be made.
So it is important to determine the characteristics of the soil: its capacity of load, resistance to the compaction and characteristics of drainage. Never build on black cotton floors, as they are weak and do not have enough capacity to support the floor, even for small stores. The warehouse and accesses to it will have to be protected from running water by an effective drainage system, and the room must be able to accommodate such a system.
To facilitate access and movement of stocks, the store should be located as close as possible to a main road. It is also important to ensure that approaches to the store will allow the vehicles easy movement and maneuverability around it. This means that, in addition to the area to be occupied by the warehouse, there should be plenty of useful space around it. Also, looking to the future, there should be sufficient space for the construction of additional warehouses and utility buildings.
In tropical countries it is very important that the long warehouse shafts are oriented east-west as close as possible. In this way, the side walls are less exposed to the sun and variations in temperature inside are minimized. If the warehouse can not be oriented to the east, some benefit can be derived from locating it in the direction of the prevailing wind. The interior can be effectively cooled by opening all doors and windows at appropriate times.
Finally, considering that the grain in the warehouse will probably be fumigated with lethal gas for humans (see Chapter 8) from time to time, it is important that the site chosen is at a safe distance from housing houses, shopping centers And other areas of work.
Standard warehouse design (for information on fumigable warehouses, see Annex 4)
All stores consist of a floor, walls, a roof and one or more entrances. However, they can vary considerably in the detailed composition and construction of these basic components; And they can include others, such as fans, windows, artificial lighting, etc. The various combinations of possible characteristics have to be considered very carefully, together with other factors relating to location, intended use, etc., when planning the construction of a warehouse.
Primary importance should be attached to ensuring that the quality of the product to be stored will not be affected by physical factors such as humidity and heat. Whenever possible and practical, the store design should incorporate features that protect its contents from rodent and bird attacks, and facilitate the use of insecticides.
The warehouse should also be easy to clean and maintain (there is no point in using components that are not easily replaceable or repairable); And it must provide good working conditions.
(I) Foundations and Floor
Unstable clay soils and areas that have been filled should be avoided whenever possible, as they involve the risk of sinking. In all cases, it is necessary to excavate to a point where the soil pressure is 150 kN / m2 or better.
The soil should be able to support the weight of the grain that will be stacked on it, and also must be impermeable to groundwater. For these reasons, the floor must consist of a reinforced concrete slab placed on a well compacted hard core, with a moisture barrier sandwiched between the two. This moisture barrier should consist of a layer of asphalt, bitumen or a polyethylene film.
The reinforced concrete slab must be made with expansion joints, to avoid cracks (which hampers storage hygiene). It should be covered with a cement cover a few centimeters thick, which becomes smooth and hardened (to prevent the formation of dust). Ideally, the concrete slab should be placed after the roof is completed: to prevent the direct sun from drying too fast, and possibly causing it to crack.
The floor level should be high enough above ground level to ensure that water does not enter the store, even after the highest rainfall that can be expected. Consideration could be given to erecting the warehouse on a raised platform about 1.2 meters above ground level to facilitate the loading and unloading of vehicles; But this alternative is expensive and can add 40% to the cost of construction.
(Ii) Walls
Most modern warehouses are built with a structure, usually of reinforced concrete. The support pillars are connected to each other by lower struts, which are fixed to the floor slab, and by the upper struts that firmly hold the frame. It is essential that all joints are secure and accurate, and that the reinforcing rods are well covered with concrete. The warehouse walls are built between the supporting pillars.
If the support posts are thicker than the walls, it is important that the additional thickness is on the exterior of the building so that the internal surfaces of the walls are smooth and free of projections. This facilitates cleaning of the store, and prevents interference with other operations as well.
The walls may be made of blocks of breeze, or of bricks of stabilized earth of 15 to 20 cm of thickness, and must be made smooth by both sides. They should be painted white, on the inside for easy detection of insect pests, and on the outside to help keep the store as fresh as possible. Alternatively, the walls may be made of a lightweight material such as asbestos cement, galvanized sheet metal or aluminum sheet. However, walls of this type are easily damaged, have poor insulating properties, and are sometimes prone to erosion.
A vapor-proof barrier must be built into the base of the walls to prevent moisture from rising and causing damage to the storage structure and contents. In addition, a strip of concrete about 1 meter wide should be placed around the outside of the store to prevent rain from eroding the base of the walls below the wet course.
(Iii) Roof
The internal pillars supporting the roof frames should be avoided because, as noted above, they may interfere with pest control and other stock management procedures. Instead, roof frames must be designed in such a way that the weight of the roof is transferred to the support columns (in framed buildings), or to the walls if the store is small.
Modern engineering techniques allow very large "free crossbar" ceilings (ie ceilings without internal support pillars) to be constructed. However, such roofs are very expensive and are rarely used in building warehouses. A steel portal frame should be used if the section should be greater than 15 meters. Warehouses below this width may have reinforced concrete roof frames.
Wooden or bamboo roof frames are only suitable for warehouses of no more than 4 or 5 meters wide. The wood used must be well dried and treated with a preservative.
The roof covering may be galvanized steel or aluminum sheet, or cement asbestos; The latter being more fragile but with better insulating properties. Tiles are not recommended, especially for large warehouses.
The roof should protrude from the pediments by 0.7 to 1.0 meters, and the eaves by at least 1 meter. This ensures that rainwater falls off the walls; And it avoids the need for gutters and drainage channels, which can be blocked or help rodents enter the warehouse. The overhang also helps keep the walls cool and protects the ventilation openings from rain.
(Iv) Ventilation
Ventilation openings are necessary to allow air renewal and reduce the temperature in the warehouse, also allow some light to enter. If these openings
Localized too low can be the source of numerous problems: entry of water, rodents, thieves, etc. These problems are avoided when fans are placed under the eaves. They should be installed outdoors with anti-bird grills (20 mm mesh) and inside (10 cm behind the racks) with 1 mm mesh (removable for cleaning) that will deter most insects.