6 Flashcards
- is the process of adapting the program to the
unique features of the site.
*It contains proposed plans that are spatially organized on the site.
-This means that the development objectives and protect vision are already set in place.
Conceptual Design
- balances human needs (rather than human wants) with the carrying capacity of the natural and cultural environments. It minimizes environmental impacts, and it minimizes importation of goods and energy as well as the generation of waste.
Sustainable design
These general precepts give rise to a more explicit set of principles for physical planning at the site scale.
Responsiveness to site and contextual conditions demands consideration of a diverse set of physical attributes and regulatory constraints.
Context-Sensitive Design
- Spatial variation in elevation produces slopes that have both a gradient and an orientation.
Site Topography
A retaining wall is a structure built for the purpose of holding back, or retaining or providing one-side lateral confinement of soil or other loose materials.
Retaining Wall
- used for walls of up to about 10-12ft in height.
- It is usually constructed with plain concrete and depends completely on its own weight for stability against sliding and overturning.
- It is usually so massive that it is unreinforced.
- Tensile stresses calculated by the working
-stress method are usually kept below 1.6 𝑓 ′ 𝑐.
Gravity Retaining Wall
- fall between the gravity and cantilever types.
- they depend on their own weights plus the weight of some soil behind the wall to provide stability.
- Semi-gravity walls are used for approximately the same range of heights as the gravity walls and usually have some light reinforcement.
Semi-gravity Retaining Walls
- the most common type of retaining wall.
- generally used for heights from about 10-25ft.
- stem: the vertical wall
- toe: the outside part of the footing that is pressed down into the soil.
- heel: the part that tends to be lifted.
Cantilever Retaining Walls
- retaining walls with cross walls are behind the stem (i.e., inside the soil) and not visible.
- crosswalls are used when the bending moment at the junction of the stem and footing become so large.
- Used in heights greater than 20-25ft.
Counterfort Walls
- retaining walls with visible cross walls (i.e., on the toe side).
- are somewhat more efficient than counterforts because they consist of concrete that is put in compression by the overturning moments, whereas counterforts are concrete members used in a tension situation, and they need to be tied to the wall with stirrups.
Buttress Walls
- commonly placed at a property boundary or next to an existing building.
- abutments may very well have wing wall extensions on the sides to retain the soil in the approach area.
- in addition to other loads, abutments will have to support the end reaction from the bridge.
Other Types
- are made of wire gabion baskets or cage filled with
rocks. - Gabion baskets are secured together to create the desired length.
- This construction is among the strongest available and used
commercially to stabilize shorelines and riverbanks from erosion.
Gabion Walls
- are synthetic fabrics
with physical and engineering
properties that are used to
enhance soil properties or to
improve structural performance. - are a subset of
geosynthetics
Geotextiles
plastic nets or grids used for soil reinforcement.
Geogrids
impervious rubber or plastic sheets used for water or vapor barriers.
Geomembranes