SEC 3 part 4
why is it important to reinforce concrete??
(usually with steel) is improtant bc concrete is very strong in compression but weak against tension forces. tension forces w conrete slabs, walls, usually arise w temp change. As temp increases, the concrete structure will try to elongate and it will crack. The reinforcing tends to reduce this tendency. When greater loads are placed on concrete surfaces and/or the temp changes dramatically over the year, the better a concrete structure needs to be reinforced.
mortar
- Bonds unit together - Waterproofs structure - Compensates for size variation of units - Integrates steel reinforcing into whole of structure
two basic types of grout
- Sanded & non sanded
Admixture are added to concrete in order to:
- improve workability - reduce water requirement therey increasing strength - entrain air. improves durability and resistance to thermal (freez/thaw) degradation - make more liquid for easy pouring - alter the setting time either accelerating or retarding - integral color
Measurements of rebar
- rebar sizing is done in 1/8 inch increments - #4 rebar is 1/2 inch in diameter - #5 rebar is 5/8 inch in diameter * typically use #4 and #5
properties of concrete
-contains mixture of cement, aggregate and water. -cement acts as the binding agent (contains silica, lime, aluminum and gypsum). water is the catalyst of chemical reaction. Aggregates provide much structural strength and constitutes the main volume of the mixture.
Galvanic Corrosion
-dissimilar metals will corrode when in contact. -true in pipe plumbing, structure fabrication and metal fasteners -corrosion potential is heightened in coastal, non arid and industrial areas. -use non conducive spacer like rubber or PVC bw two metals
precast concrete pavers
-have more compressive strength than most cast in place concrete; -compressive strength exceed 8000 psi -exceptionally durable and more resistant to wear than other concrete products - comes in variety of shapes, sizes and colors - comes in two thicknesses: one for pedestrian pavements (2.25 iches thick) and one for vehicular pavements (over 3" thick)
why are Admixtures added
-improve workability -reduce water requirement so it increases strenght -entrain air, improves durability and reistance to thermal (freeze thaw) degradation -make more liquid for easy pouring -alter the setting time either accelerating or retarding -integral color
granite
-very hard and durable -used for street and pedestrian paements, curbs where available - reasonably maintain its frictional coefficient throughout its life - can be finished to varying degrees of smoothness, from mirror-polish to rough cleft. Difficult and expensive to shape, cut and finish, impermeable
board foot
1' x 1' x 1"
Material or construction techniques for marine environment
1) Sites close to ocean will be subject to stressors: - tidal fluctuation; strong winds; tsunamis or hurricanes; salt in the air or wind driven spray from the ocean; high water tables near the shore; wave action 2) structures need to be elevated to deal with tides. Enclosed structures should be elvated quite a bit to deal with potential storm surges during hurricanes. Buildings are built w pole foundations. Winds will need increased design for live loads on structures 3) Plant materials will need to be adaptable to marine envt and endure salt air or fog and wind shear due to higher winds 4) Construction materials like stainless steel, aluminum, coper recommended bc of increased moisture and salt induced corrosion
Principles of asphalt design
1) Structural stability of asphalt is derived from the subgarde and aggregate base 2) Prevention of standing water or water entering the subgrade is essential 3) Aspalt pavig needs an edge or extended base course beyond the edge of AC
problematic characteristics in nursery grown plants
1) circling roots or severely root bound in pots 2) poor form 3) broken branches or deformed branching structure 4) presence of disease organisms or insect pests 5) damage to bark 6) severely stressed plants
nitrogen
1) natural sources are blood meal, alfalfa meal, feather meal, fish emulsion, manure 2) signs of deficiency: pale yellowish green (chlorosis), stunted appearance, thin stemed, lower leaves more affected than upper
phosphorus
1) natural sources: rock phosphate, guano, bone meal 2) signs of deficiency: stunted, thinned stemmed, spindly foliage often red or purple
potassium
1) natural sources: the edges of oldest leaves begin to yelloow (chlorosis) and die (burned edge look) 2) signs of deficiency: potassium sulfate, granite dust, wood ash and kelp meal.
Relative character of each metal
1. Aluminum 2. Zinc 3. Steel 4. Iron 5 Nickel 6. Tin 7. Lead 8. Copper 9. Stainless Steel metals close to each other are ok to combine. zinc, steel, iron are friends. lead and copper are friends. z,s,i are not friends with lead and copper.
National Grading Rule lumber classses
1. structural light framing grades , No 1, 2, 3 (highest strenght) SLF 2, lgiht framing grades (highest strength not required (construction, standard utility) 3. STUD, suitable for interior and exterior wall frame 4. SJ&P: structural joists and planks (engineering grades for larger sizes) 5 MSR machine stress rated - each piece tested and rated mechanically
slump testing process
1. the cone is filled with concrete in 3 layers of equal volume 2. Each layer is rodded 25 times w a steel tamping rod 3. the top is then smoothed and the cone lifted vertically off the concrete 4. the amount of slump is then measured.
other pressure treatment of wood
1. wolman salts, 2. osmosalts fluor chrome arsenate phenol 3. wolmanized natural select, copper azole, A (CBA-A) and B (CA-B)
caliper
A measuring tool with two usually adjustable jaws used especially to measure thickness or diameter.
Advantages/Disadvantages of Asphalt
Advantage: inexpensive, chemical resistant, low glare, recyclable, quick installation/usability, flexible Disadvantage: high heat gain, flexible, low psi resistance, poor structural integrity in heat, damaged easily if unsupported, erodes easily if exposed to concentrated water flows
rebar; score joints
Aggregate size must be coordinated with ____ and ____. Too large of aggregate will impede placement of rebar and creation of joints by not allowing ample clear space
ACQ
Alkaline Copper Quartenary
ACA
Ammonical Copper Arsenate, ACZA, CZC used in hard-to=penetrate woods. (not commbonly avaialble0
Redwood lumber grades - CONSTRUCTION HEART
An economical, all purpose grade, good choice for posts, decks and smaller garden projects, all heartwood and small knots
CCA
Chromated Copper Arsenate (too toxic, not used anymore)
Plain sawn lumber
Cut in a way that the growth rings are parallel to wider face of the board
DBH
Diameter at breast height (for existing trees) 4'-6" above ground
glass fiber reinforced concrete
Embedded in Portland cement and sand (concrete mixture). Used for ornamental structures, wall cladding, and soffits. Precast
steel
High strength, Low-high corrosive resistance Low-med $ Med weight
stainless steel
High strength, high corrosion resistance, high $$$, high weight
Redwood lumber grades - MERCHANTABLE
Larger looser knots and more imperfections, heartwood and sapwood are both included so ground contact may be permissible on aboard by board basis, shrinkage to be expected
Micronized Copper Quat
MCQ
primary plant nutrients
Nitrogen (N) Phosphorus (P) Potassium (K)
annual
Plants that flower and die in one season
moisture content
S-GRN (surfaced green (above 19%)
bush hammered (stone finishes)
Safety: may be suitable for exterior paving if machine bush-hammered. - rought textured hand finish from striking with a hammer and chisel
split face (stone finishes)
Safety: poor pedestrian surface - stone is split along its grain revealing natural grain and rough texture.
Southern Pine Grademarks
See page 115 for lumber order measurement
walking surface
Size, texture, color and abrasive property of aggregate must be coordinated in a concrete mix to be poured as a ____.
Material or construction techniques for high water table
Structures: if water table reaches or rises above bottom of a footing or foundation, the soil bearing strength will be reduced to point that structure will settle, causing it to sink uniformly. Adverse effects on plants/trees esp.
transpiration
The release of water from plant leaves. Plants put down roots into the soil to draw water and nutrients up into the stems and leaves.
nominal size
The size of lumber when it is cut from the log
water
Too much of this reduces the stregth of concrete
Types of cement mixes
Type 1: normal Type II: moderate sulfate resistance Type III: high early strenght Type IV: low heat of hydration Type V: high sulfate resistance White Cement
mortar types
Types M, N, S, O
nursery standards
Using the standard has many benefits for designers and contractors, not the least of which is simplifying the procurement and acceptance processes by relying on clear pre-defined standards for quality and size of nursery stock. Defined by American Standard for Nursery Stock
on-structure plazas, paving, walls
Weight of aggregate must be considered when used in concrete for ____, ___ and ____
exposed
Wood in landscape construction is commonly ____ to the elements.
Codes, trade standards
___ and ____ set rigid guidelines to ensure public safety. Most concerned with protecting the wood through the use of an applied material or preventing contact with the ground.
size, texture, color, abrasive property
___, ____, _____ and _____ must be coordinated in a concrete mix to be poured as a walking surface
weight of aggregate
_____ must be considered when used in concrete for on structure plazas, paving and walls
aggregate size (concrete)
_____ must be coordinated with rebar and score joints. too large of aggregate will impede placement of rebar and creation of joints by not allowing ample clear space.
alloy
a compound consisting of two or more metallic elements. practically all commercial metals are alloys
sandblast
a designer finish that does provide texture. specified as light, medium or heavy. can be used to expose aggregate
pozzolan
a finely powdered material which can be added to portland cement to increase durability. fly ash is one type of pozollan
salt finish
a finish with a distinctive look. fine pits increase surface area, cooling the paving in hot weather.
espalier
a fruit tree or ornamental shrub whose branches are trained to grow flat against a wall, supported on a lattice or a framework of stakes.
mastic
a generic term for pasty materials used as protective coatings or adhesives
gneiss
a hard, durable metamorphic rock that usually has visible layering in its structure. unlike slate, it will not split along defined planes. Not as common as other types.
epoxy
a high strength copolymer used to bond metal, glass, masonry and plastics. Can be used as a protective coating and as an adhesive. Rebar can be coated with epoxy for corrosion protection and can be used as an additive in grout mixes.
tack coat
a liquid coating of asphalt applied to the base course or exsting surface to be paved
pH
a measure of how acidic/basic water is. The range goes from 0 to 14, with 7 being neutral. pHs of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base.
loam
a mixture of clay, sand and silt and benefits from the qualities of these 3 different textures, favouring water retention, air circulation, drainage and fertility easy to work with and provide good drainage very fertile.
caulk
a paste like material used to seal joints and gaps. Silicone, polurethane, and polysulfide are common base materials for caulks
pollarding
a pruning system involving the removal of the upper branches of a tree, which promotes the growth of a dense head of foliage and branches.
galvanic corrosion
a reaction that occurs when two different metals come in contact with each other in the presence of moisture
silt
a sediment material with an intermediate size between sand and clay. Carried by water during flood it forms a fertile deposit on valleys floor. The particle size of silt ranges from 0.002 and 0.06 mm. low plasticity. when wet it becomes a smooth mud that you can form easily into balls or other shapes in your hand and when silt soil is very wet, it blends seamlessly with water to form fine, runny puddles of mud.
cylinder test
a test to determine the actual compressive strength of concrete installation and typically performed 7 to 28 days. Test involves pressing the cylinder in a hydraulic press until the cylinder breaks.
steel
addition of carbon to form an alloy increases strength and reduces the melting point.
top seeded exposed aggregate
aggregate is sprinkled onto wet slab, brushed and washed to expose. Can be slippery if stones are polished or smooth
Redwood lumber grades - SELECT HEART
all sounds heart wood, available in surfaced or unsurfaced condition, usually not kiln dried, knots permitted
bronze
alloy of copper and tin. includes other elements. Harder and more durable than pure copper. Almost as hard as wrought iron and less brittle, corrosion resistant. Doesn't oxidize.
Admixture
alter the basic attributes of concrete, allowig specailied uses.
admixtures
altera basic attributes of concrete, allowing specialized uses. this is added before or during the mixing of concrete
galvanizing
application of a protective coating of zinc to the surface of a ferrous metal to protect it from corrosion
90 minutes
as a general rule, cocrete should be poured within _____ of adding the water. Mixing generally occurs off=site at a local mixing plant and is delivered ready-mixed by truck (more cost effective). the Mix can be specially ordered to specs including color admixture. For remote job sites or major concrete construction jobs like large dams, on site mixing may be economical.
wearing course
asphalt and aggregate mixture for use as exposed surface of paving profile. sometimes called surface course
full depth design
asphalt is placed directrly on prearpeard subgrade with no base
stock sizes and shapes of metals
available in standard forms and dimensions. some stock items to know: -bars, flats, squares and rounds (solid stock) - pipe: hollow round - tube (hollow rectangle) - angles (tee, L, I, W, S, Zee, M)
glu-lam
beams composed of long pieces of wood glued together to meet a specific span/bearing: can be very strong and span long distances. * see page 112 (bark side up illustration)
spanning members of wood
beams, joists, rafters decking.
English brick bond
built with alternating courses of stretchers and headers where a header is centered above a stretcher. The joints of the stretcher courses align and the joints of the header courses align
fly ash
byproduct of combustion of coal in power plants, and can be added in place of a percentage of the cement (usually 20%). This is done for environemntal reasons (form of reuse/and reduces the need to produce cement, which is an energy-intensive process. slows curing process.
secondary plant nutrients
calcium CA, magnesium Mg, sulfur S
exposed aggregate
can be achieved by washing away the top surface of cement after a certain amount of curing has occured. curing retarder can be applied to the top surface. dilute hydrochloric acid can als be used
slump test
can indicate problems with: water content; aggregate gradation, temperature, hydration, setting, and air content.
Two categories of concrete
cast-in place, pre-cast
structural glued
catchall term for a variety of glued members. Can be used for structure if graded.
resistant or very resistant to wood rot
cedar, redwood, black locust (for posts), teak/ipe (for deck)
stainless steel
chromium, manganese, nickel, molybdenum are added to the ferrous base as alloying elements. RESISTANT to corrossion. High Strength, greater THERMAL Expansion, low thermal conductivity and highly reflective surface. uses: sanitary furnishings, street furnishings, railings, fasteners and most metal item in marine environments
location
climate, microclimate (.e.g. shade, sun, wind, salt spray), soil conditions, site location (for plant selection considerations)
'galvanized' metal
coated in zinc. usually done on iron or iron alloys (like steel) to prevent rust
5000 psi
common for structural concrete or for use in high, large vehicle traffic areas
mortar
composed of cement, water, lime and well graded samd. Used to join mutliple units together. Can achieve aeshetic results.
lift
compressed layer of asphalt installed in one application. e.g a 6 inch lift may contain two 3" lifts. 4" to 6" is ually the maximum depth of a lift.
cement
concrete contains cement! they are different
tooled/trowelled finish
concrete is worked with a masonry tool to achive a smooth, even finish. too slick for outdoor surface
Cast-in Place (CIP) concrete
concrete mixed near or on the construction site & poured into formwork. Reinforcing is placed prior to pouring the concrete mixture. the concrete cures on site and finishes are applied at the site. most site flatwork, curbs and walls are cast in place. ex. sidewalks, patios, retaining walls, build framework out of wood then poured.
70-85%
concrete reaches ____ of its 28 days strength at 7 days
pre-cast concrete (PCC)
concrete that is formulated and cast in molds at a fabrication shop. Cured units are delivered to site for installation. Can be crude (e.g. drainage pipe, manholes or other drainage cstructure and septic tanks wall caps, containers, pcc pavers, it's extra strong and made in factory/delivered to site.
ferrous material
contain iron in the compound
15 gal, 36 ich box
container sizes
balanced fertilizer
contains equal parts each of NPK
wrought iron
contains less carbon than cast iron and is worked by hammer into shapes. lower carbon composition makes the metal softer and more malleable. common uses include decorative fences, railings, furniture and grilles.
cast iron
contains more than 2% carbon and poured into molds. it has good compressive strength but poor tensile strenght. Common uses include tree grates, pipe and ornamental work.
Sanded grout
contains sand particles for texture and strength. Can be used only on joints greater than 1/4"
compete fertilizer
contains the 3 main plant nutrient elements (NPK)
availability
contract grown, tagged specimen, new hybrid, historic species. (for plant selection considerations)
cost
contract grown, wholesale, specimen, salvaged, transport cost (for plant selection considerations)
mixing (of concrete)
critical when it comes to addition of correct ingredient quantities and careful mixing of concrete. All components should be combined thoroughly into a homogenous medium.
travertine
decorative stone mainly used for veneers and pavements. type of limestone that forms in geothermal springs. when liquid cools, it forms deposits of the stone. it is relatively soft and usually has small pock-marks in its surface. its been used as a building material for over 2000 years.
marble
decorative stone used for veneers and pavements. formed from limestone that has metamorphosed, been densified by heat and pressured. Favored by stone sculptures
borate pressure treated lumber
deep penetrating treatment, considered less toxic than others (not as available)
how does intense sunlight and dry air affect wood?
degrades wood by breaking down the medium that binds the wood fibers.
natural finishes
designed to allow wood to color naturally and can provide some degree of water repellancy
concrete pavers
designed with spaceers cast in to them which creates larger joints bw the units in order to form more permeable pavement surfaces. they are installed and swept with coarse sand or fine clean gravels as permeable joint fillers
type IV low heat of hydration cement
develops strength more slowly than other types. intended for use in massive structures.
caliper
diameter of tree truk at 6" above grade (for field grown nursery stock and small trees)
Climatic Concerns with wood
different geographies yield different effects on wood in the landscape.
rough sawn
dimensioned as called out 2x4 equals 2"x4"
copper based wood preservatives
do not use with plain steel, electro-plated steel, or aluminum fasteners . use copper, stainless steel, hot dipped galvanized, hot dipped glavanized or specialty coated fasteners instead.
Incomplete fertilizer
doesn't contain one or more of NPK (e.g. 20-6-0)
moderately resisant to wood rot
douglas fir, eastern white pine, tamarack
flemish bond
each course is made up of alternating stretchers and headers. Each header is centered on a stretcher above and below.
Asphalt
easy to place, inexpensive. an ingredient of crude petroleum or is refined out of petroleum, a dark brown or black cementitious material, final paving product is typically called this, strong adhesive waterporoof.
pleaching
entwine or interlace (tree branches) to form a hedge or provide cover for an outdoor walkway.
carbon steels
exhibits poor corrosion resistance. it's ncessary to increase resistance by adding copper as an alloying element, galvanizing, or providing another protective surface treatment. Common uses include furnishings, structures, railings, brackets, fasteners
3000-3500 psi
expected normal strength (for cylinder test)
type V: high sulfate resistance
for use where soils or groundwaters have a high sulfate content
grout
formed by cementitious material and fines, teh same as mortar without hydrated lime. mixed material is creamy and smooth. Some grouts contain additives as latex to provide a flexible medium. Colors are easily varied to achieve particular looks.
sedimentary rock
formed by deposition and subsequent concretion. generally softer and lower in density than igneous and metamorphic rocks
common brick bond
full headers every 6th course or flemish headers every 6th course. a course of headers inserted every five or six courses. A header is always centered on a stretcher and the joints of each course of headers always align. see pic p 129
Type 1: normal (cement)
general purpose suitable for all uses where other properties not required. Ok for most landscape uses.
how is stone classified?
generally by how it was formed, its mineral composition, and the size and orientation of its cyrstalline structure
sawn
generally rough enough to be a non slip surface outdoors. saw arks usually show
GFRC
glass fiber reinforced concrete
Redwood lumber grades - CONSTRUCTION COMMON
good all purpose material but for above grade construction only, contains sapwood, shrinkage to be expected
general lumber grades
grade o a piece of wood is based on number character and location of imperfections that may reduce strength, durability and appearance of the wood. Lumber is stamped at the mill including thee codes: 12, WP, S-DRY, R, D Fir, Stand, (see page 113 for pictures)
seasoned wood
greater strength, better nail-holding ability, greater dimensional stability, less weight, better decay resistance and better ability to hold paint and preservatives than 'green' or unseasoned wood.
Bluestone
hard, durable stone. term is generic rather than geologic. Pennsylvania bluestone is sandstone, Shenandoah Valley bluestone is limestone. from australia - baslat or slate. comes in many colors shapes sizes. used for paving and wall caps.
survivability/dependability
hardiness of species, effect of all the mainteance, location, cost, availabaility
Dressed Lumber (surfacing)
has been planed
Rough lumber (surfacing)
has not been planed.
Hardwood and softwood
have no direct relation to any actual physical property of the wood
heat of hydration
heat released during curing process
maintenance
hedge, appropriate location (e.g in front of window), knowledge of staff (for plant selection considerations)
gypsum
helps poor soil condition by improving heavy clay soil structure and remove sodium from saline soil. no effect on soil fertility, soil structure, or ph of other soil types.
Material or construction techniques for windy sites
high winds create # of design issues. plant may be bet or even sheared off by persistent high winds or gusts. planted windbreaks are a potential solution to lessening the effect of winds. Wind erosoin on agricultural lands in the midwest plain states can be a serious issue. avoid use of brittle plant mtrls like silver maple and empress tree. Wind loads on structures require increased live loads for structural design on walls, fences, decks and overhead structures
Redwood lumber grades: CLEAR
high-quality finished lumber similar to "clear, al heart" but may contain sapwood, some small knots, and medium surface checks, usually kiln dried, expensive
Redwood lumber grades: CLEAR, ALL HEART
highest quality, can produce a face entirely clear of defects, excellent stability, usually kiln dried, expensive.
pine, softwood
highly susceptible to elements. its structural capabilities are maintained when used inside the wall
asphalt concrete
hot mixture of liqued asphalt and well graded aggregates
soil structure
how particles of soil are grouped together into aggregates
Porphyry
igneous stone with large cyrstals, but most commonly refer to redbrown purple stone that was prized by Romans and used for items associated w the Emperors. Extremely hard and impermeable. Not as common as other types of stone
running bond
intermediate as far as stability. (pattern should be perpendicular to traffic direction)
prime coat
layer of low viscosity asphalt to aggregate or subbase to plug voids and prepare base for overlaying asphat course
slate
layered, flaky metamorphic stone, which sometimes chips at edges. not as durable/safe for pavements where it may be damaged under heavy use. It is easily spllit into fairly thin pieces (1/4 ich) and is a very waterproof material. favored as a roofing material during the Victorian era
basket weave paving pattern
least stable
copper
limited in landscape use. Ideal material for specialized applications. Good corrosion resistance, highly malleable and easily welded and formed. surface corrdoes and oxides/patinas when exposed to moisture or outdoor. Common uses: pipe, flashing, decorative surfacing, sculpture
aluminum
low strenght high corrosion resistance med-high $$ low weight
copper
low strength med-high corrosion resistance high cost med weight
Type O mortar
low strength mortar for no exposed locations. For interior load bearing and non load bearing walls, not suitable for freezing conditions when wet.
slump cones
made of metal w a 4" top opening and 8" bottom hole.
stack bond
made up of courses of stretchers where each stretcher is stacked directly above a stretcher and the joints align. This is not a structural bond and is generally used on interiors for non-load bearing walls.
Appearance framing grades
many species-specific terms, including Clear, Knotty, Heart
terrazzo
marbe chips embedded in a cementitious matrix. most modern ones are epoxy resin or polyester resin. Chip materials can include glass, porcelain or other materials. (low maintenance but not suitable for outside)
humus
material formed from decaying leaves and other organic matter; soil amendment and treatment/DEFICIENCY: add organic fertilizer, manure, compost, leaf mold
tree caliper
measurement of the diameter of a tree trunk, in inches. These trees are planted as babies in farm fields and grown to more mature sizes. When they're harvested, the root zone is wrapped in burlap, set in a wire cage to protect the root mass, and safely held together with twine - called balled & burlapped (B&B) plant stock
iron
medium strenght Low corrosion resistance low cost medium weight
seal coat
mixture of fine aggregates and slow setting emulsfied asphalt to seal prevoiusly paved surface
Quarter sawn lumber
more expensive to produce than plain-sawn due to the time and material waste but edge grained lumber has less tendency to develop surface checks, splits and twists over time.
running bond and herringbone patterns
more stable. herringbone being the strongest in cars
slump test (ASTM C143)
most common method of testing concrete. Effective in that it determines suitability of the mix before it's poured and measures the relative uniformity of the batches.
ACQ
most common, less toxic alternative
herringbone pattern
most stable. strongest pattern becase a lot of friction between other bricks
running brick bond
most used bond and is composed of stretchers offset by 1/2 brick per course. It is often used in cavity wall construction reinforced with metal ties back to the main structural wall.
MCQ
newer alteranate to CCA
Micronutrients
nitrogen, phosphorus, potassium, sulphur, magnesium and calcium
lumber sizing
nominal size is size before seasoning and surface lighting/ dressed dimension are typically a half inch less than called out (S4S- surfaced four sides) e.g. 2x4 actually measures 1.5" X 3.5" (SURFACED FUR SIDES)
stack bond and basketweave patterns
not appropriate for vehicular paving
Board foot calculation
number of pieces * thickness in inches * width in ft * length in ft e.g. (15) 2x4's that are 8 feet long equal 80 board feet
#5, #10 #25
nursery container size for trees, shrubs, evergreen
Material or construction techniques for permafrost
on the surface and to some depth (depens on climate0 is the ACTIVE ZONE. this zone is where soil is sometimes forzen and sometimes thawed. below this sone is Permafrost layer. this layer is where ground is always continously frozen. somewher below the permafrost is soil that is always thawed
porous asphalt
open graded asphalt and aggregate mixture. allows water to pass thru asphalt layer, fines may tend to clog pores over time
Material or construction techniques for riparian zones and floodplains
outside of regulatory issues that arise from building in these areas. Enclosed structures within floodplains should be avoided on the LARE. Old ref manual prohibits this. But sports fields and park areas are considered compatible land uses. riparian vegetation is uniquely adapted to conditions of soil and soil moisture. Plant native riparian plants (sycamores, lowland maples, river birch, native poplars, willows)
alkaline
pH above 7
acid
pH less than 7
neutral
pH of 7
headers course
placed vertically in a standard two brick width wall to add strength by bonding both sides together
flowering tree
plants are those which produce noticeable flowers.
perennial
plants that can live for three or more growing seasons
silicone
polymers that include silicon, carbon, hydrogen and oxygen. They are heat resistant, non stick and rubber like. Uses imclude sealants, adhesives, lubricants and insulation
Common types of stone in the landscape
porphyry, granite, gneiss, slate, bluestone, quartzitic sandstone, standard sandstone, marble, limestone, travertine
bitumens
predominant constituent of asphalt
PTDF
pressure treated douglas fir (resistant to rot and insect)
Antidessicant
prevent plants from drying out. they are compounds when applied correctly, slow the loss of water from plants. They work by creating a thin barrier over the leaf stomata (the leaf's pore) locking in moisture. beneficial at times when roots are unable to take up sufficient water due to a lack of available ground moisture.
Material or construction techniques for high fire hazard areas
primarly in western states; - use fire resistant mtrls - create defensible space around structures - remoe dead vegetation and reduce fuel loads - create separation bw vertical layers of vegetation to avoid fuel ladders - use plant sthat have low resin content or high moisture content
photosynthesis
process by which plants use sunlight, water, and carbon dioxide to create oxygen and energy in the form of sugar.
corrosion
process in which a metal reacts with water in the presence of oxygen to produce an oxide
paints
protect wood from weathering (sunlight and water), but do not provide decay or insect resistance
Type M mortar
recommended for masonry below grade and in contact with soil. very high compressive strength/durability, but low in tensile stregnth and poor workability
aeration
reduces compaction, oxidizes the soil and allows the roots to take the appropriate nutrients and grow as vigorous as possible
"thin set"
refers to an application process and the thin layer of mortar is used like glue to attached the tile
quartzitic sandstone
relatively durable and used for building and pavement. Metamorphic rock and relatively easy to identify due to gliterring quartz crystal in the matrix.
igneous rocks
rocks formed by cooling of molten rock. tend to be denser and harder than the other major types of rock.
metamorphic rocks
rocks that have been subjected to pressure and temperatures that alter their crystalline structure. usually intermediate in density and hardness
float finish
rough preliminary leveling pass, tool or smoothing out concrete surface
Exterior pavement (safety)
sandblasted, sawn, thermal/flame finish
calcium, magnesium and sulfur
secondary macronutrients
CMU block
see page 125 for illustration
non sanded grout
smooth consistency and appearance, recommended for smaller joints
limestone
soft sedimentary stone composed of calcium carboates, sometimes w magnesium carbonate. subject to erosion by acid or acidic rainfall. Generally been formed in lake deposits or in marine environments. Crushed limestone is often used as road aggregate, to make portland cement, and as a soil conditioner to make soils less acidic. Stain easily from rust, oil or grease.
Standard sandstone
soft, brittle easily damaged, often used for flagstones. comes in variety of colors. Standard sandstone and travertine are two stones that are least resistant to surface abrasion
aluminum
soft, lightweight, malleable material. High conductivity and thermal expansion. for construction uses - achieves the desired balance of strength and resistance to corrosion. common uses: lamp posts, furnishings, sculpture
iron
soft, malleable metal (based ingredient in wrought iron, cast iron and steel)
stock commonly available
solid stock; pipe or tube; tubular (aka hollow structural steel); angle
slightly or no resistant to wood rot
southern yellow pine, yellow poplar, spruce (these rot too fast)
broom finish
specified as light, mediu and heavy. medium is a common texture for outdoor walking surfaces
portland cement
standard gray cement. it's made by heating a limestone and clay mixture in a kiln and pulverizing the resulting material called hydraulic cement (bc it hardens by reacting with water but also forms a water-resistant product)
steel, stainless, aluminum
stock is commonly available
honed finish
stone is cut and sanded - iffy for exterior paving
polished
stone is cut, buffed and plished for brilliant, reflective, smooth finish. not acceptable for paving outdoors.
thermal/flame finish
stone is cut, then put under intense flame cuasing top layer to burn off. leaves a texture finish. good for outdoor paving surfaces.
tumbled
stone tiles are placed in a rubber drum with water, small rocks and sand. the drum is turned to achive a worn finish on the stone. Not sued as exterior pavement
thin units
stone veneers, tile * must be set on a rigid structure to prevent future cracking.
properties of wood
structural character, decay and insect resistance, climactic concern, types of wood
Type II: Moderate sulfate resistance cement
sulfates in moist soil or water can react with concrete, causing expansion, scaling, and cracking. because of increased availability, type II is commonly specified regardless of a specific need for sulfate resistance
sandblasted
surface is blasted with compressed air and an abrasive material. often finishes are classified as light, medium or heavy. make suitable pavement surfaces or exerior enviornments
drawback to wood construction
susceptibility to rot and degradation by insects. dry rot mold and termite borings threaten the structural integrity.
broadleaf evergreen
tall trees with large leaves that remain green all year
grouting
term frequently used to describe filling the open cells in CMU block with concrete, the material used is mortar, not grout.
decidious
term used to refer to a tree that sheds its leaves during a particular season each year
salinity
the amount of salt in water
allelopathy
the chemical inhibition of one plant (or other organism) by another, due to the release into the environment of substances acting as germination or growth inhibitors. Trees are great examples. many trees use allelopathy to protect their space by using their roots to pull more water from the soil so other plants cannot thrive. ... Other trees that are known to exhibit allelopathic tendencies include maple, pine, and eucalyptus.
sand
the coarsest soil, with particles 0.05,2.0 mm in diameter. It is most extensively used construction material. It consists of particles of rock and hard minerals, such as silicon dioxide. They are the largest type of soil particles, where each particle is visible to naked eye. The large, relatively stable sand-particle size increases soil aeration, improves drainage in tight soils and creates plant-growth supporting qualities, or tilt.
seasoning
the drying of wood by the use of air or heat.
clay
the finest of all the soil particles, measuring fewer than 0.002 mm in size. It consists of microscopic and sub-microscopic particles derived from the chemical decomposition of rocks. Clay is a fine grained cohesive soil. They stick together readily and form a sticky or gluey texture when they are wet or dry. they hold a high amount of water. expand when in contact with water and shrink when getting dry.highly compressible and its strength is very high when dry, which is why it is used in construction as mud mortar.
Heat of Hydration
the heat released during curing process (concrete)
hardwood
the wood from broad-leaved, mostly deciduous trees
chlorosis
the yellowing seen on the leaves of plants when they cannot make chlorophyll due to a lack of magnesium ions. Possible causes of chlorosis include poor drainage, damaged roots, compacted roots, high alkalinity, and nutrient deficiencies in the plant
Material or construction techniques for expansive clay soils
these soils swell up when wetted and shrink when dry. have low infiltration and percolation rates and dry out very slowly. Plastic when wet and tend to deform under load. When wet, they have poor structural properties. When dry, tend to crack and become hard and difficult to excavate wo machinery. 1. Moisture control important factor in site design. Doe with subsurface drainage. under or around structures; the use of chemicals or lean concrete to stabilize the soil (using these alternatives will create coditions hostile to plant grwoth.
grout
thin mortar used for filling spaces
28 days
this is when the design strength is achieved with concrete testing (cylinder)
plant massing characteristics
to achieve a design purpose
anodize
to coat a metallic surface electrolytically with a protective oxide coating. This can provide a metal with a finished surface with color and/or various degrees of luster.
water, strength
too much much ____ reduces the ______ of concrete
brass
type of alloy. used in irrigation valves. zinc is added to copper to form alloy brass. VERY malleable, can be machined, cast into a form. Can be made very smooth and good for objects requiring low friction. Common uses: pipe fittings, hardware, decorative fixtures - it resembles gold in color and shininess. Corrosion resistant
Fiber mesh or welded wire mesh (WWM)
used for higher strenght - light duty reifrocing in CIP concrete. WWM is often placed incorrectly and does not have enough cover - will rust. Fiber mesh will not rust.
Redwood and cedar
used for siding because of its natural resistance to isnects and rot. some woods provide natural protection from decay.
Type N mortart
used in masonry above grade subject to exposure. Good workability, medium compressive strength and bonding strength. A general purpose mortar.
paint
used not just to change the colors of base materials, but to seal and weatherproof their surfaces. It's an effective sealant against moisture penetration and will protect base metals agains corrosion
stains
used primarily for aesthetic effect, provide mildew resistance, UV protection, water repellancy. can be semi transparent or solid colord
pressure treatment/ Chemical preservatives
used to provide protection from insects and decay-causing fungi. Oil/water based, environmental effects, finshing
type III high early strength cement
used when forms must be removed quickly, or where structure must be put to use quickly
white cement
usually type I or III. Used when a light color is desired. expensive.
most common type of masonry wall uses this
veneers of stone or brick over CMU or concrete cores. Many older walls were made of solid stone or brick. Ancient walls built by romans often consisted of masonry shells backfilled with rubble and dirt or rubble and mortar
tropical hardwoods
very dense, weather only on the surface. their relative weight makes use in structures ineffecient
Type S mortar
very high tensile bond strength. Excellent for masonry subject to severe weather exposure. Excellent workability. Used for reinforced masonry.
Redwood lumber grades - SELECT
very similar to "select heart" but used where termites and decay are not problems, contains sapwood
enemy of asphat
water
structural character of wood
wood construction extremely versatile and relatively simple. Very popular to use. Readily available. Offers the flexibility of both spanning and vertical support.
softwood
wood from trees with needelike leaves.
how does wet climate affect wood structures?
wood structures must be design to shed water. tree source selection can also improve durability
air-dried
wood that has been seasoned by exposure to the atmoshpher. most lumber in arid climates is air dried.
kiln-dried
wood that has been seasoned in a kiln under controlled temperature and humidity.
what does a post (wood) demonstrate?
wood's compressive strength