Instructor's Manual for Earthquake-Resistant Construction in Peru

These plates are in constant motion, and where they meet, one will try to move over the other, causing pressure to build up over time. This pressure will eventually cause a break deep below the surface, resulting in an earthquake. Earthquakes can be expected in areas where these plates come together. In Peru, the Pacific Plate is moving under the South American Plate, resulting in a high risk of earthquakes. The epicenter of an earthquake is the point on the earth's surface over the place where the breakage occurs. The earthquake causes vibrations to go out in all directions from the epicenter, known as waves. The forces of an earthquake can cause significant damage to buildings. When an earthquake strikes, the earth begins to move backwards and forwards along the same line. The foundations and lower part of the house move with the earth, while the roof remains stationary. As the shock waves hit the wall, different parts of the wall begin to move in opposite directions, causing damage. The damage caused by an earthquake depends on the height and weight of the walls and roof. The height and weight of the roof must be added to that of the walls. In Peru, it is recommended to build light roofs using materials such as paJa, calamina, iternit, or palm leaves. Tiles should be avoided if possible. The forces of an earthquake can also push walls into one another. If the earthquake pushes on one wall, much of the force and weight is then transferred to the walls to which that wall is attached. If the quake moves parallel to the direction of long walls, only the smaller end walls are likely to be damaged. However, if the quake moves parallel to the small end walls, much greater damage can be expected. To withstand the forces of an earthquake, it is recommended to build square or rectangular-shaped houses. An "L"-shaped or "T"-shaped house is not recommended. If the earthquake strikes the house at an angle, it will push the walls in opposite directions, causing the house to twist on its foundations. A strong house must be built in a special way. The forces of the earthquake push on walls in opposite directions, so it is essential for parallel walls to have equal weight. Otherwise, the earthquake will push more on the heavier wall, and the building will try to twist on its foundations. To balance the forces of an earthquake, it is wise not to have more openings on one side of the house than the other. To make a house strong, you must have roughly equal openings in parallel walls. For every door or window in one wall, there should be an opening of roughly equal size directly opposite in the parallel wall. To provide strength to a building, it is essential to balance the doors and windows. The force on a building increases with the weight and height of the building. To build a strong wall, it is necessary to use some method of reinforcing the wall in the corners and adding some materials inside the walls to give them additional strength. The Modern Adobe system is a new method of strengthening walls that has been developed by the Oficina de Investigación y Normalización del Ministerio de Vivienda y Construcción. This system involves using two new types of adobe blocks, which have canals on two sides. When two blocks are put together, the canals form a hole through which reinforcing rods can be passed.