![Brick Masonry
B1+B2+B3
≤ 0.5L (for One Storey)
≤ 0.42L (for Two Storey)
≤ 0.33L (for Three storey)
- [600mm ≤ B4 ≥ 0.5H2)]
Horizontal distance (pier width) between two openings
should not be less than 50% the height of the shorter
opening (and not less than 600mm)
- [600mm ≤ B5 ≥ 0.25H1]
Openings to be located away from the corners by clear
distance equal to at least one fourth of the height of
opening or 600mm whichever is more
- [H3 ≤ 600mm or 0.5(B2 or B3)]
Vertical distance from an opening to opening above](https://image.slidesharecdn.com/drb01introduction-240603162651-963355b4/85/Disaster-Resistant-Building-Introduction-15-320.jpg)
Disaster Resistant Building Introduction
- 1. Disaster Resistant Building Foundation & Structural system
- 2. From GATE syllabus 2023 Part- A – Section-2 – Construction & Management Principles and design of disaster resistant structures, Temporary structures for rehabilitation; Part- A – Section 7: Services and Infrastructure Firefighting Systems; Building Safety and Security systems; Building Management Systems;
- 3. Types of Foundation and their Uses 1.Shallow foundation 1. Individual footing or isolated footing 2. Combined footing 3. Strip foundation 4. Raft or mat foundation 2.Deep Foundation 1. Pile foundation 2. Drilled Shafts or caissons
- 4. Details for foundation • Procedure for construction of foundation starts with decision on its depth, width and marking layout for excavation and centerline of foundation. • Foundation is the part of structure below plinth level in direct contact of soil and transmits load of super structure to soil. • Generally it is below the ground level. • If some part of foundation is above ground level, it is also covered with earth filling. • This portion of structure is not in contact of air, light etc., or to say that it is the hidden part of the structure. • Footing is a structure constructed in brickwork, masonry or concrete under the base of a wall or column for distributing the load over a large area.
- 5. • Depth of Foundation • Depth of foundation depends on following factors: • Availability of adequate bearing capacity • Depth of shrinkage and swelling in case of clayey soils, due to seasonal changes which may cause appreciable movements. • Depth of frost penetration in case of fine sand and silt. • Possibility of excavation nearby • Depth of ground water table • Practical minimum depth of foundation should not be less than 50 cm. to allow removal of top soil and variations in ground level. • Hence the best recommended depth of foundation is from 1.00 meter to 1.5 meter from original ground level. • The width of footings should be laid according to structural design. For light loaded buildings such as houses, flats, school buildings etc. having not more than two storeys, the width of foundation is given below: • The width of footing should not be less than 75 cm for one brick thick wall. • The width of footing should not be less than 1 meter for one and half brick wall. • Width of Foundation / Footings
- 6. EARTHQUAKE RESISTANT DESIGN OF FOUNDATIONS: • Foundation is a substructure built below the super structure. Purpose of the foundation is to transfer the structural loads safely to the underlying soil. Safe and economical design of a foundation under different loading conditions is the role of geotechnical engineer. • Proper design of a foundation against earthquake loading requires through understanding over the behavior of soil, response of structure and interaction of soil-structure under earthquake loading.
- 7. • These are as important as disaster resistant structural designs. Infect the methodology for construction also should be designed for disaster resistance. • We should have proper implementation of the structural details so as to let the structure behave as envisaged. • The quality and methodology of construction is equally important. For example we use cover blocks. If the cover blocks are not cast properly in good quality concrete then they facilitate concrete deterioration. Ultimately this affects durability and serviceability of the structure. • The Durability and serviceability are the key elements of any structure. Ensuring Quality in construction will enable achieving durability and serviceability as a desired end result. Disaster Resistant Construction Techniques
- 9. 1. Settlement pattern and Design Considerations PROVIDE - Clustered (zigzag) planning avoids tunnelling effect and reduces susceptibility to disaster AVOID - Row house settlement with roads leading to Sea PROVIDE - Simple Square/Rectangular and Symmetrical plan is Suitable - Length of Building ≤ 2xWidth. PROVIDE - Separation of wings into different rectangles in plan is preferable PROVIDE - Shorter wall facing wind direction AVOID - Longer wall facing the direction of wind
- 10. 2. Foundation PROVIDE - Slightly Slanting cut - Sand Compaction thickness more than 150mm - PCC thickness more than 75mm AVOID - Straight Cut - Sand compaction less than 150mm - PCC less than 75mm PROVIDE – A. Foundation width should be 2½ times thickness of the wall or 0.8m, whichever is more B. B. Use baked bricks and stones C. Minimum depth should be 1000mm AVOID A. Foundation width should not be less than 2½ times thickness of the wall B. Never make a wall without foundation C. Don't use unbaked bricks in the foundation PROVIDE - Foundation on Hard Soil AVOID - Foundation on Loose or Soft Soil
- 11. 3. Walls PROVIDE - Average wall height should be 2700 to 3000mm AVOID - Too High Walls PROVIDE - Average wall height should be 2700 to 3000mm AVOID - Too High Walls Stone Masonry A. Through stone should be placed horizontally at a minimum spacing of 1200mm center-to-center B. Through stone should be placed vertically at a minimum-spacing of 600mm
- 12. - Vertical Rod should be placed at 125mm from the inner face of the Brickwork Rat-trap Bond (T-Joint) - Vertical Rod should be placed at 245mm from the inner face of the Brickwork Rat-trap Bond (L-Joint) Vertical rod must be connected using extra “L” bar with main steel of Plinth band and Lintel band. The bar will be able to perform efficiently if it is anchored at Foundation - Locate the vertical bar at 165 mm from the outer face of 230 mm wall English Bond (L-Joint) 1. Joints in brickwork should be staggered. 2. For regular bond use only mortar of 1:6 or richer and for Rat - Trap bond 1:5 or richer. 3. Vertical rods should be protected with a minimum cover of 40mm in M20 concrete.
- 13. Sectional View of Disaster Resistant Wall Reinforcement in Siesmic Beams and Bands Disaster Resistant Beams and Bands in the Walls A. Grade Beam (In case of Frame) B. Plinth Band C. Lintel Beam RCC Band Details
- 14. Openings are the most Vulnerable part in a building. Large shear forces get accumulated around openings and therefore, edges of the openings should be specifically strengthened. Due to lateral thrust openings are subjected to movements attempting to make them a Rohmbus - stretching opposite diagonals as shown. Because of this it is likely that after an Earthquake; diagnonal / shear cracks occur around unsecured openings and brick piers. 4. Openings No Corner Reinforcement - Diagonal Cracking in building with no Corner Reinforcement No Cracks in Buildings with Vertical Reinforcement Protect Openings with Reinforced Band all around as shown. Detail of reinforcement is shown in cross-section of the Jamb at ‘t” Design Considerations - Avoid too many openings in the wall -The minimum distance between unreinforced openings should be 600mm
- 15. Brick Masonry B1+B2+B3 ≤ 0.5L (for One Storey) ≤ 0.42L (for Two Storey) ≤ 0.33L (for Three storey) - [600mm ≤ B4 ≥ 0.5H2)] Horizontal distance (pier width) between two openings should not be less than 50% the height of the shorter opening (and not less than 600mm) - [600mm ≤ B5 ≥ 0.25H1] Openings to be located away from the corners by clear distance equal to at least one fourth of the height of opening or 600mm whichever is more - [H3 ≤ 600mm or 0.5(B2 or B3)] Vertical distance from an opening to opening above
- 16. Placing vertical bars and closed ties in Column PROVIDE - Adequate Lap Length with slope of 1:6 AVOID - Insufficient Lap Length Splice with Offset Cranked bar in a Column PROVIDE - Bend the Stirrup through 135° AVOID -Inadequate Stirrup Details Min concrete Grade for RCC should be M20 i.e. 1: 1.5 :3 for volumetric proportioning. Where 3 is a mix of 10mm and 20mm down aggregates in 50/50 or 60/40 ratio. Columns & Beams
- 17. Reinforcement Detail of Beam Beam bars bent in joint region overstress the core concrete adjoining the bends A. Reinforcement Detail of Beam Column Joint at Roof Level B. Reinforcement Detail of BeamColumn Joint at Floor Column should have minimum four 12 diameter bars. It is preferable to use TMT bars near the coast line. Column & Beam Junctions
- 18. CYCLONE - Structures should be erected in areas, which provide a protective shield from high winds with natural firm level foundation. Flat roof arrangement should be avoided. So should be the projecting elements like antennas and chimneys, eave projections, sunshades etc. The construction should have adequate diagonal bracing, reinforced machinery, thicker plate glass, and anchoring of purlins to gable ends. As far as flood resistant housing is concerned, prohibited zones should be totally avoided. Layout of the buildings/ houses should be such that they do not block free flow of water. Construction should be done on raised mounds. Waterproofing treatment, adequate bracing, afforestation in catchment areas are required for flood- prone areas. The Expert Committee Report covered the following issues: Identification of various hazard-prone areas Vulnerability and risk assessment 'of buildings Outlining the disaster damage scenarios Technical guidelines for hazard resistant construction of buildings Upgradation of hazard resistance of existing housing stock by retrofitting