Kutch Navnirman Abhiyan
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Design of a seismic-resistant Rural Primary School
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Documentation March 15, 2001

Anusandhan has been working on design proposal for a Rural Primary School along with seismic safety features using local materials and local skills. The fundamental ideas are as follows.

1. Seismic Resistant
2. Cost Effective
3. Use of local material as much as possible
4. Low maintenance - Repairs/ Maintenance/ Modification etc. posible
locally
5. Aesthetic and merges with rural milieu

The school should provide an environment that is beneficial for children physically, mentally and spiritually. The designed environment has to offer opportunities for various teaching and learning processes as per modern pedagogy and philosophy of education. In context of rural school, following guidelines form the basis of proposed design.

Design Concept

1. In rural tribal societies, the child is exposed to the natural elements and materials at a very early age. He is comfortable being outdoors rather than indoors. Even the house interiors is seldom used during the daytime. A school is probably the one of the first built environment that he is supposed to be in during the day. Therefore it is important that the school is friendly, comfortable and welcoming physically and psychologically. This will be help in reducing the number of dropouts. That's why, the class rooms should have a feeling of openness rather than that of confinement. It is with this thought semi-covered spaces are proposed to be designed instead of totally closed and confined rooms for the initial formative period of young children. The teaching spaces grow more formal in later stages of education and for grown up students after finishing primary education, totally covered space may be provided.

2. The starting point as in all the projects must be a realistic assessment of educational requirements & of cost and affordability. The purpose of a primary school classroom is to protect learners and teachers from excessive rain, sun, wind and dust. And a semi covered space with all pedagogical consideration which gets good lighting, has cross ventilation and overhangs to protect the opening from the rain is appropriate enough. With limited and scarce resources, It is possible to make larger and more variety of teaching - learning spaces in such a way rather than just two confined small spaces. Design has to provide spaces that are comfortable in local climatic conditions. Tropical climate of Kachchh is to be considered. It has to be cool during summers, warm in winters and something that protects from monsoon rains. Therefore, the building is proposed to be built around a courtyard which besides being a good place for interaction also acts as a climatic element in harsh tropics. Mangalore tile roof, the traditional method of draining roof water, is also a climatically appropriate choice.

3. Building should require low maintenance as these are public buildings with scarce funds. Actually it is one of the most important factor for a good building and if possible, the money saved from cost effective designs and technologies should be used for creating a maintenance fund by involving village community. Participatory process, thus, assumes great significance to generate the feeling of ownership amongst people.

4. The building requirements grow along with people and the village. Hence, the building design is intended to grow with the time. The present requirements, the minimum, are built in such a way that future expansion of building takes place in a way so as to complement the existing building. Over a period of time more class rooms might be added. Hence the plan provides for systematic growth pattern. Effort is to evolve a pattern which can grow and be complete at each stage of growth. The space which is complete by itself becomes part of a larger whole and then of a still larger whole. Design should take care of the way additions can be made without disturbing the existing structure.

5. For education of children, functionally it may be the best to provide a variety of learning spaces. But in conventional, so much money is spent on building classrooms that nothing is left for other types teaching learning spaces, in form of courts, open plinths or verandahs, chabutara under trees or a grove.

Class Room Design

1. Pedagogy - The class rooms are designed for various pedagogical needs of teaching and learning processes. Pedagogical needs require two important design features.

(a) A lot of display and storage spaces within the class rooms to allow usage of charts, maps, models and other teaching aids.

(b) Possibility of using the space in various ways to seat the children so as to accommodate various activities of performance, story-telling and group works, etc. The proposed plan for the class room is designed for such an environment where there are lots of learning opportunities with lots of potential of flexibility.

2. As for protection against pilferage of educational items and school property, lockable cup-boards are provided and a small room which is totally secured is provided to be used as store or a teacher room.

3. The reduction in cost is achieved by breaking free from closed - door classrooms and bringing in some innovative semi-covered space as classroom. During interventions for DPEP, it was felt that if a lockable almirah is provided along with a fully secured store then a semi-covered classroom can be more appropriate option. Hence, class rooms proposed are semi-open eliminating doors and windows and reducing wall volumes. This saving enabled us to emphasis open space designs.

4. The combination of semi-open classrooms and courtyards also makes it easier for multiple class teaching as entire space can be visually overseen and supervised by one teacher from other space. And not only in the present case of our school but more often than not, single teacher has to do multi-grade teaching. With all these ideas, it is still not an imposition by the designers on the community to have such class rooms, There fore, it is always open to the community, the teachers and children to make it as they feel like it i.e. keep it semi-covered or close it up. It can easily be closed at any later date as and when needed. Compound Wall Next point after appropriate class rooms is surrounding the space with a 'compound' (with a wall/fence). This is extremely important to allow to create a variety of external spaces some open, some shaded, some partly enclosed, other may be paired with shade trees or may be with consolidated earth covered by shade trees. And all these spaces while being open need to be protected to create a sense of safety and protection. The teaching space needs to be surrounded also to allow appropriate maintenance with least effort and energy besides protecting from stray cattle. In the proposed design it is achieved by surrounding the court by classrooms so that only a small length of wall is sufficient to enclose the open space. Since the building itself acts as the boundary wall of open space enclosed, external boundary of the site needs to be protected by only vegetative hedge of cactus and bamboo, to avoid any encroachment etc.

Proposed Structural System

The proposed structural system is based on following fundamental ideas.

1. Cost effective
2. Low maintenance
3. Use of Local Material and skills as much as possible
4. Aesthetics and merges with rural milieu.

5. Repairs / Maintenance / Modifications etc. possible locally Another important criteria for choice of structural system and associated technology is to use the opportunity of this rehabilitation programme after quake to build capacity of local communities to manage themselves during future hazards. It is critical that instead of imposing alien technology, local artisans and petty contractors are trained into adapting improvements in local technologies. With these above ideas in mind following technology is proposed to be used. Walls stone/ Brick in lime-cement mortar with lime-cement plaster inside and lime-cement pointing outside.Because Stones are locally available, cost effective, thermally better. Pointing outside and plaster inside takes care of long term maintenance. This technique has been used by people of the area for years without any problems. Roofs Mangalore tiled hipped roofs with sky light and vents on steel understructure and Partially Pre-cast joints and sand stone / brick panel roofs (CBRI technology) Because

  a.. Mangalore tile roofs are local forms, cost effective, known to local people and easier to erect. Steel understructure provides long term option instead of wood and also wood is scarce and expensive.

  b.. Maintenance is quite low and doesn't have any problems of leakage, can be repaired or modified locally by artisans.

  c.. Partially pre-cast joists with panel roof are good alternative for the RCC roof. It is not only more cost effective, but also easier to construct as no form work is required, aster to erect and also better quality control is possible due to pre-casting on the round. It is also possible to train local artisans easily for this technology.

Openings

For doors and windows, it is proposed to use steel angle frame and wooden shutters Because steel frame last long and are termite proof. Wooden shutters are made of local wood as these are cost effective, locally repairable or modifiable, and safe. Floor Finish IPS for Interiors and Brick paving in outdoor spaces Because The are cost effective and allow playing with colours, textures and patterns for evoking children's interest. These finishes besides other advantages are also easy to maintain without any long term liability.

Seismic Strengthening

1. To strengthen the stone walls, through stones to be used. At least one in every 9 sq. ft. If stone of sufficient size are not available, dumbbell shaped pre-cast RCC bond elements.

2. Seismic bands to be provided at plinth level, lintel level and roof level that bind all the walls in a box like way. It increases the strength of the buildings significantly.

3. The corners to be strengthened by using corner stones and by providing reinforcement in the corners. The corner reinforcement should be tied with seismic bands and the roof.

4. Hipped roofs (four-way slope) are better than gable end roofs (two-way slope). But appropriate ways of using gable end roofs can improve the performance.

5. Roof to be tied down under-structure well to the walls. Wall plate to be provided to anchor the roof on the walls. Roofing tiles to be secured properly on the under-structure.

6. In case of flat roof, partially pre-cast joists and panels to be used in conjunction with RCC diaphragm. And anchor the roof to the walls.

7. Bracing or corbelled support to be provided to projections.

8. Parapet walls to be strengthened by making them smaller, by providing pilasters and by making an RCC coping on top.

Suggested Precautions for Cyclone

1. Use of 'wind breaks'. Studies show that instead of solid barriers like walls permeable barriers like belt of trees are more effective and provide greater depth of protection. Optimum porosity is around 30% to 50%.

2. Flat roofs result in negative pressures (suction). RCC roof is stable due to heavy weight but is not appropriate because of many other reasons. Inclined roofs are more appropriate.

3. Care with projections such as 'chhajjas'. They are subjected to uplift forces.

4. No long stretches of continuous walls and walls to be strengthened by adding columns or cross walls to resist the wind pressures. 5. the frames of doors and windows to be anchored properly in the walls. 6. Simple and strong bolting device for doors and window shutters. Other Alternative Features of The Design Four important ideas can be integrated in the design. 1. Roof Water Harvesting 2. Wind Tunnel for Passive Solar Cooling 3. Net and Pan Run off water harvesting on surrounding open land
4. Two pit Pour Flush Toilet

1. Roof Water Harvesting

Water being scarce resource in Gujarat, Water conservation ideas are extremely important ideas. In water scarce Kachchh district, most of rain water runs off and percolation is little. Water availability is extremely low and sometimes even after lot of trying one doesn't get water at certain locations. Therefore, roof water collection is an important idea, that needs to be considered. The calculation for quantity of water as roof water run off is done based on the following formula Total quantity - K P A (Where K is run off coefficient, P is average annual precipitation, and A is plan area ) Based on above formula, water coming from two roofs is collected in a water tank, which will be demonstrative technology to be promoted for all public private buildings. The tank is to be covered with precast joist roof and the top can be used as a chabutara in the spill out area and a small handpump can be installed to use the water. Roof water gutters are taken down and connected to water storage tank.

2. Wind tunnel for cooling

To provide cooling to the covered spaces a wind channel by making brick jali wall can be made and laid out to reach all the class rooms, the wind that enters the tunnel through vines and bamboo trellis cools down as it passes through the ground and near the water storage tank then it passes into the room to cool it. The opening of wind tunnels are designed in spill out area near the water storage tanks approximately at the distance of minimum of 10 mtrs. from the built space.

3. Net and Pan run off water harvesting

Net and pan is basically a horticulture concept which uses the surface water run off in a very effective way. The channels are dug in a grid like manner across the natural slope of the land in such a way that site gets divided in small squares and each square leads water to flow into channels. At the junction of these channels a small ditch in shape of pan is made to plant the trees. By doing this all the surface water of the sloping land flows towards the trees planted and irrigates the vegetation. This is specifically good for areas with less percolation. On the upper part of the ridge trees which require lesser water are planted and at the bottom the ones requiring more water.

4. Toilets

The toilets proposed here are UNICEF promoted designs for better sanitation. The WC is connected to 2 soak pits and while one pit is being used the valve to other is closed. The toilet is flushed clean by pouring water manually so that only rationalized quantity of water is used. The urinals should be attached to another separate soak pit. The female urinal should be designed by taking need of young girl children of school going age. The soak pit is made out of jali wall in 9" thick walls and is covered with the pre-cast joists and panel roof.