Technology & the Built Environment

Post and Beam

Post and beam construction is a type of building frame in which roof and floor beams rest directly over wall posts. It is also a traditional system of wood-frame construction which was started to use during 19th century. And it has its roots in the Egyptian cultures of 2,000 B.C.

In post and beam construction, solid timbers are connected by mortise and ten on joints and secured together with oak pegs. It contrasts with the alternative style of construction, which involves nailing wood studs together into a frame and then covering it with interior Sheetrock panels and exterior plywood or other engineered wood product. The connection of post and beam is a powerful bond.

Benefits:

• Building time
• Aesthetics
• Fire resistance
• Energy efficiency
• Online references
• Open living spaces
• Stability

Disadvantages :

The biggest disadvantage to a post and lintel construction is the limited weight that can be help up, and the small distance required between the posts. The arch developed by Roman allowed for much larger structures to be constructed.


Flying Buttresses

A flying buttress, or arc-bout ant, is a free-standing buttress attached to the main structure by an arch or a half-arch to support or reinforce it. The buttress seemingly flies through the air, rather than resting on the ground and hence is known as a flying buttress. It is usually made of brick or stone. We can often find flying buttresses in Gothic architecture usually on a religious building such as a cathedral. They can be seen in the cathedrals of Chartres, Le Mans, Paris, Beauvais, and Reims.

Purpose: It provides horizontal strength to a wall. The majority of the load is carried by the upper part of the buttress, so making the buttress as a semi-arch provides almost the same load bearing capability. It also serves as a bridge, carrying the lateral thrust produced at the base of the arches and domes due to their weight, across to the outer buttress, which is massive enough to absorb the pressure.

Benefits:

• Light
• Cheap
  
  
  
  
• Stability
• Ability to make building taller
• Ability to make building glorious

 







Dome/Arch

A dome can be considered as an arch which has been rotated around its vertical axis. The arch is still one of the greatest architectural discoveries of all time. It was the only way to hold roofs up without beams until the 19th century. It has been found in many early civilizations and some have been found as early as Mesopotamia. The Egyptians used arches in tombs and vaults and the Greeks used arches for practical construction. Nowadays, arches are used majorly in bridges.

Benefits :

• Reducing tension
• Self supporting
• Ability to hold amounts of weight on a multi-level scale
• Ability to create long structures
• Stylistic

 Types of Arch/dome :

• Triangular arch
• Round arch or Semi-circular arch
• Segmental arch
• Unequal round arch or Rampant round arch
• Lancet arch
• Equilateral pointed arch
• Shouldered flat arch –see also jack arch
• Horseshoe arch
• Three-centered arch
• Elliptical arch
• Inflexed arch
• Ogee arch
• Reverse ogee arch
• Tudor arch
• Catenary or Parabolic arch

Load Bearing

Load bearing is a type of construction which can support an imposed load in addition to its own weight. Load bearing structures are structures where the load is transferred to the foundations via load bearing internal and external walls e.g. masonry houses, pyramids in Egypt. They are characterized by having a small window to wall ratio (i.e. more structural wall area than window openings) and internal walls. Due to the large stresses within the brick or stone walls the height of load bearing structures is limited.

Load- bearing walls are the one of the earliest forms of construction. The development of the flying butress in the Gothic architecture allowed structures to maintain an open interior space, transferring more weight to the buttresses instead of the central bearing walls. Notre Dame Cathedral, for example, has a load- bearing wall structure with flying butresses.

Benefits :

• Construction savings
• Labour
• Materials
• Overhead
• Air conditioning and heating
• Sound transmission