Quick Notes Flashcards
When specifying lumber for use on a wooden deck, the lumber should always be
faced bark-side up
by orienting lumber bark-side up, cupping or warping of the deck lumber will be limited to the center of the wood, not the edges (i.e. where adjacent pieces of lumber sit parallel to one another along their long edge). Cupping at the edges of lumber creates a trip hazard that can easily be reduced or mitigated by placing deck lumber bark-side up.
Vegetated swales can be used to accommodate large storm events:
generally be designed to safely convey a 25-year storm event.
Note that they will often be designed to handle 2-year design storms without experiencing erosion.
Isolation or expansion joints
Are used in concrete to allow lateral movement between adjacent slabs or other fixed structures/surfaces, and as such, should be constructed to the full depth of the concrete slab.
Should also be placed at the interface between concrete and other fixed surfaces, for example, where a horizontal concrete surface meets a structure.
Stormwater infiltration rates are determined primarily by
Soil type
Infiltration
The movement of water through soil, rock or other material in the ground and, as such, infiltration rates are determined primarily by soil type.
Primary Purpose of Bid Form
Standardize all bids submitted so that they can be compared accurately to one another
In the absence of a bid form, contractors may format their bids in a variety of ways, making it difficult or impossible to accurately compare bids between contractors with the same scope of work.
Stabilized Inlet
Typically constructed with riprap - relatively large angular rocks that diffuse the velocity of water entering a stormwater treatment facility.
Silt Fences
Typically laid out along the contour of a slope to maintain water quality during construction activities.
Generally composed of a fine plastic mesh that retains and filters sediments from stormwater while also allowing water to pass through the plastic membrane.
To avoid or rehabilitate compacted soils, what measures should be taken during or after construction:
- Determine if compaction is located in the surface or in the subsoil
- Amend soils with organic matter
- Limit the use of heavy equipment during construction process
- Avoid use of heavy equipment during or directly after precipitation events, as wet soils are more readily compacted.
Site Protection Plan
a plan or plans that, in general, protect natural resources on a project site, sensitive areas adjacent and downstream of the project site and comply with local laws and codes.
Examples of content in a site protection plan include tree protection and salvage, site access, erosion control measures, and noise control.
Stormwater BMPs attempt to accomplish:
Aimed at infiltrating stormwater, thereby mimicking the natural hydrological regimen and recharging groundwater.
Also aim to reduce stormwater velocity and volume, as doing so improves water quality and reduces the potential for erosion during storm events.
In general, BMPs do not attempt to detain stormwater over long periods of time, although cistern structures and other rainwater harvesting devices would do so.
Likewise, BMPs do not channelize stormwater flows, as channelization results in high water velocities that will erode stream channels and reduce water quality when released into natural water systems.
Lower peak flow, not base flow.
Continuous Beam
Beam supported by at least three structural members (posts) on a wooden deck or other elevated structure.
Note that all beams are load bearing and that the portion of a beam overhanging a post could be referred to as “cantilevered”
Gravel Ballast
Recommended feature of green roofs along their perimeter to protect against wind shear.
What three materials are found in typical concrete mix?
Water
Aggregate
Cement
Under general conditions, properly constructed asphalt pavement requires surface maintenance or resurfacing every:
20 years
Bituminous Binder
Used to adhere a new coat of asphalt to an existing asphalt surface.
Mortar
Used to bond individual masonry units
Epoxy
a high-strength adhesive that is used to bond wood, concrete, metals and/or plastics in general construction
Asphalt Treated Base
An alternative to untreated base material and is typically used during construction in wet or freezing conditions
Plate Compactor
Used to compact an aggregate product during a construction process
The ratio of which two materials determines the compressive strength of concrete
Water and Cement
W/C Ratio
Reducing peak flows can help control:
- stream siltation
- soil erosion
- downstream scouring
- channel widening
- frequency of severe floods
Mitigating land subsidence
Usually achieved through groundwater recharge and stormwater infiltration
Proper dust control on a construction site has the primary benefits of
Reducing the volume of sediments produced by construction activities
Live Staking
Bioengineering
Inexpensive and simple technique to restore eroded stream banks.
Cost-effective and low impact way of reducing sediment deposition and erosion in waterways
Concrete Pros and Cons
Pros:
- extremely workable and able to be used and applied to a wide variety of purposes
Cons
- susceptibility to cracking
- prolonged curing time (~28 days)
- need for rebar and formwork
Sediment Forebay
- Often located upstream of a constructed stormwater wetland or other infiltration device to intercept and reduce the velocity of flows entering the wetland and to settle sediments and other solids that may be present in the water.
- Helps improve the water quality within the wetland structure and improves its efficiency and operational lifespan.
Rational Method for Calculation of Peak Stormwater Runoff Rates
- typically used for small drainage areas
What materials should only be placed behind a retaining wall to facilitate drainage
Compacted aggregate with filter fabric
All construction details should include
- scale to which detail is drawn
- dimensions
- Callouts for materials and other relevant annotations
To be most effective, sediment traps should be located
at point of discharge
doing so allows this water quality device to treat runoff before it disperses over a greater area and potentially gains greater flow velocity.
Which irrigation system minimizes water loss to the greatest extent?
Point-source drip irrigation
Are among the lowest use irrigation systems available and would thus minimize water loss to the greatest extent.
Point-Source Dripp Irrigation
- emitters are located at the base of each shrub or plant and provide a low volume of water to the root ball of each plant, thereby ensuring that the vast majority of water conveyed by the irrigation system is used for its intended purpose.
What actions offer the most improvement to a site’s safety
- increased site usage
- improving visibility
- designing for natural surveillance
- providing multiple access points
- promoting a positive image of the site
- defined perceived ownership of the site
Vertical Curves
PVC - Point of Vertical Curve
PVI - Point of Vertical Intersection
PVT - Point of Vertical Tangency
PVC is beginning of vertical curve (sometimes referred to as the BVC (beginning of vertical curve))
PVT is something referred to as EVC (end of vertical curve)
Borrow Pit Method
Grid Method
- used to calculate cut and fill quantities on complex grading projects
- approach entails laying out a grid across a construction site and assigning an elevation to each point on the grid. Note that the spacing of the grid correlates to the accuracy of the estimate (i.e. a finer grid produces more accurate results). The elevational values for each cell are then averaged, and an average cut/fill values is assigned to every cell. Note the cut and fill values are kept separate. Individual cell averages are then added up and multiplied by the area of a single cell to yield an estimate for the amount of earthwork required by a project.
Contour Area Method
Average End Area Method
Snap ties
type of fastener used to hold formwork together while concrete is being poured and are designed to break away after the formwork is removed. Snap ties can remain inside concrete to provide additional reinforcement.
As a general rule, aggregate used in a concrete mix should not exceed:
1/3 the depth of slab
Recharge Trench
- placed adjacent to and downslope of a vegetated filter strip
(Water would sheet flow off of an adjacent surface, flow through the filter strip for treatment and then enter the recharge trench for infiltration)
Instructions to Bidders
Purpose of this form is to outline the requirements necessary to prepare and submit a bid properly and provides detail guidance to bidders, including the process for award of contract and rejection of bids
Bid Form
General Conditions
Supplementary Conditions
Invitation to Bid
Asphalt Treated Base (ATB)
an alternative to untreated base material and is typically used during construction in wet or freezing conditions.
Acts as a water-resistant barrier that prevents the infiltration of fines into the subgrade, which occurs when water accumulates in the subgrade. (Not only does this clog the base layer (thereby impeding drainage), it can also create voids in the subgrade into which the pavement can settle.)
ATB is about three times as strong as an untreated granular base (such as crushed rock). Possible to use thinner layers for the same structural support, which can save on excavation costs.
Tensile strength
measurement of a product’s resistance to forces parallel to the material’s grain or surface. (most often associated with wood)
Landscape Lighting Best Practices
- facilitate safety
- improve legibility of a space
- establish a uniform layout of lighting fixtures
- consistent and thoughtful placement of lighting fixtures provides users with a safe means to negotiate a space in the evening and early morning hours.
- Uplighting should be minimized whenever possible give that it results in light pollution.
(maximizing lumen output would be a goal in scenarios like lighting a parking lot, it would not be considered a best practice). Light fixtures should be selected based on their appropriateness for their intended application and not simply based upon the amount of light they produce.
Measures to directly address soil compaction for urban street trees
- use of suspended pavements (pavements that do not transfer loads to subsurface planting soils)
- installation of Silva Cells or other comparable systems below pavement
- Use of structural soils
Purpose of a deconstruction inventory
- meant to identify all site and building components that can be removed, reused, or recycled and can supplement conventional demolition activities
- benefits include the reduction of construction-related waste and the management of hazardous resources
- Although deconstruction can cost more than conventional demolition, when used properly, it has the potential to generate additional income for projects as well.
Sediment Forebay
- located upstream of the retention pond to intercept and reduce the velocity of flows entering the facility and to settle sediments and other solids that may be present in the water.
Doing so helps improve the water quality within the treatment structures and improves its efficiency and operational lifespan.
What unit of measurement is used to calculate live load on a wooden deck?
Pounds per square foot
What unit of measurement is used to measure water pressure in an irrigation mainline?
Pounds per square inch (PSI)
Unit Price
use when the bidding information outlines the type of work required, but not the amount
Ideal for addressing uncertain scope of work
Unit prices can incorporate any and all anticipated costs associated with the installation of the unit, including labor, overhead, profit and materials, and thus be an ideal way of ensuring that the contractor could profit from a defined type of work with an uncertain scope
Lump Sum
Cost-Plus
Backflow Prevention Device
Used to separate irrigation water from a potable water supply, thereby protecting it from contamination.
Device is located after the water meter, at the very start of the irrigation system.
Water Meter
typically provides a point of connection to a municipal water main and measures the amount of water passing through it (for billing purposes)
Quick Coupler Valves
Allows hoses to be connected to the irrigation water supply and are important and useful components, both for a site’s irrigation design and its ongoing maintenance practices
Isolation Valves
Located on an irrigation mainline to allow (or shut off) water to a portion of the irrigation system - most often for troubleshooting a leak in the mainline
As a general rule, the finished grade of the landscape should relate to the finished floor elevation of a structure by
Finished grade should be a minimum of 1 inch below the finished floor elevation of a structure
- depends on type of construction
- exterior finished grade should generally be positioned 1” minimum below interior finished floor elevation, for flood protection
- 1/4” threshold is typically provided at entrances for accessibility compliance
- although real world conditions often dictate a greater difference between finished grade and finished floor elevations (FFE) emphasis on the word minimum
- note that in exterior conditions, it is often ideal for the landscape finished grade to be around 2 inches below the finished surface elevation of adjacent hardscape surfaces such as sidewalks and pool decks, and many sources prefer a 6 inch difference between “softscape” and the FFE
What is the purpose of a pilot hole when using wood screws?
Prevent the wood from splitting and splintering when driving the screw
Compost Blankets
a 1-3” layer of compost loosely applied to disturbed soils
- prevent erosion and concentrated stormwater flows, reduce runoff, increase infiltration, promote the growth of vegetation and enhance soil stablity in general
- help protect against conditions that will create concentrated flows and high-velocity run-off. However, once concentrated flows or high-velocity run-off have been created by upstream conditions, compost blankets should not be used
Advantages of Asphalt Paving
- low maintenance costs
- low reflectivity (due to its being a dark color)
- low cost of installation
Disadvantages of Asphalt
- Susceptibility to frost damage
- Propensity to erode at its edges
Filter Strips
Filter sediments from stormwater and treat sheet flows from adjacent surfaces, thereby improving water quality.
Concrete Cantilevered Wall
Expensive to construct because walls such as these require large excavation and formwork with steel reinforcing, significant back drainage and expansion joints.
That said, after construction, a wall such as this has low maintenance costs and a long life expectancy
Project Manual
a single book or set of documents that contains all of the relevant project documents in one place, including the bidding documents, general conditions, supplementary provisions (also known as the “special conditions”) and technical specifications. Although technical specifications are included in the project manual, a project may not include performance specifications, as these are a type of specification and are thus not always found in every project manual. Design drawings are not part of the project manual
Control Joints
Introduced into concrete to prevent cracking in random locations. They resist cracking to predetermined locations.
Can be constructed in multiple ways (tooled, saw cuts, etc.) but the most visually appealing control joints in concrete are typically saw cut.
The suggested depth of control joints varies by source and locality, but most texts generally agree that control joints should extend to 1/4-1/3 of the thickness of the concrete.
Specifications are typically ordered according to a
prescribed sequence
Part 1 - General
Part 2 - Product
Part 3 - Execution
Technical specifications follow standard format that provides three types of information
General
Product
Execution
Technical Specifications
address qualitative or aesthetic-oriented information that cannot be addressed or easily shown through the designer’s drawings.
Such information would include material finishes and the quality of workmanship to be executed. The specifications themselves are typically broken down into general information, product information, and execution.
Technical Specifications
General Information
Include the basic scope of work
Technical Specifications
Product Information
describe the specific materials to be used and any manufacturing or fabrication processes to be used in producing them
Technical Specifications
Execution
Describe the actual means of preparing, installing or constructing the item in question, as well as any quality or performance requirements expected
Technical Specifications Best Practices
- Follow a prescribed format and sequence
- Take precedence over construction drawings
- Should be found in a single location within the contract documents
Vegetative Cover prevents erosion through which mechanisms:
- Shielding soil from the impact of rain
- Slowing runoff velocity through increased surface friction
- Roots holding the soil in place
- Increasing the absorption capacity of the soil through root systems
Surface Albedo
Ambient temperatures
“Fall zone” surrounding playground equipment is generally sized to:
6’ on all sides for school age children
3’ for infants and toddlers
Connectivity
Refers to the degree of connectedness in a transportation network
Liquefaction
takes place when loosely packed, water-logged sediments at or near the ground surface lose their strength in response to strong ground shaking (e.g., earthquakes)
Table of Abbreviations
typically included on the general information sheet with a construction document set for the express purpose of defining any and all abbreviations that appear within a project’s drawing set
Site Protection Plan
general term for a plan or plans that protect natural resources on a project site, while also protecting sensitive areas adjacent and downstream on the project site and complying with local laws and codes. Other examples of content in a Site Protection Plan include site access, tree or plant salvage and measures to salvage topsoil on-site for reuse.
A Site Protection plan would not encompass concerns such as security checkpoints or chainlink perimeter fencing.
Examples include: wash down areas for constrution equipment, erosion control, tree protection, storage areas for salvaged materials, noise mitigation.
Treatment and habitat value can be improved in stormwater wet ponds through which?
Using organic geometries
Topographical variation
(both create variations in the wet pond’s conditions that promote greater biodiversity and increase the treatment time of stormwater
Wet ponds generally benefit from increasing flow length and should be designed to be anywhere from 4-8’ deep.
Use of zinc coating in exterior metal applications
Non-stainless steel fixtures used in exterior applications are often coated in zinc to prevent and reduce the formation of rust. Zinc coating is added to fasteners by dipping the fasteners in a vessel of molten zinc (a process referred to as hot-dip galvanizing)
Machine Bolt Assembly
typically used for metal-to-metal connections
Purpose of slump test
To measure the workability of a concrete mix.
The test itself measures the consistency of fresh concrete before it sets by placing a portion of the concrete mix into a slump cone, tamping the mix and removing the cone. The height of the mix is then measured, as is any slump or deformation in the shaped of the concrete. Thus, the slump test not only checks the workability of freshly made concrete, but can also be used as an indicator of an improperly mixed batch of concrete.
Demolition Plan contains
- survey base with accurate locations for all existing site elements
- bold dashed line that indicates the full limits of work for the entire project
- reference notes and hardscape to be removed are other items that would need to be included on the plan.
Primary determinant of the width of a retaining wall’s footing
Soil bearing capacity
Also helps determine the method of a retaining wall’s construction
Soil Bearing Capacity
the measure of a soil to decrease in volume under the pressure of a given weight
LEED
Leadership in Energy and Environmental Design
Program developed by the U.S. Green Building Council that measures and evaluates the sustainability and performance of structures and landscapes
LID
Low Impact Development
concept that addresses hydrological flows via stormwater management, with the goal of protecting and preserving natural drainage patterns on a site during and after the development process
BMPs
Best Management Practices
address stormwater management practices - addressing issues of irrigation, plant selection and maintenance, among other things, with the goal of reducing resource use and protecting overall ecosystem health
Architectural Grid System
utilizes the proposed building grid (established by the architect) to organize and lay out elements of the proposed site construction and the grid can be used to identify locations in lieu of a survey control point.
Iocate specific site elements on a site layout plan
Emergency Access Plan
Geotechnical Soils Report
determines the character of a site’s geology and soils.
Such a report will generally contain specific recommendations for grading and drainage and should be taken into account when designing this portion of a project.
Heat of Hydration
hydration, a chemical process initiated when cement is mixed with water to form concrete.
It is an exothermic (heat-producing) reaction that occurs as cement particles expand due to the presence of water.
Ratio of cement to water determines the extent of this reaction and is the primary determinant of the ultimate strength of the cured concrete.
Invert elevation of a pipe is measured from where to where
Measured at the bottom of the inside/interior of the pipe and is measured from the surface (finished grade) of the ground.
Example: the top of a 0’-6” diameter pipe with an invert elevation of 3’-0” would be located 2’-6” below landscaped finish grade.
Three primary documents used in solicitation of bids by an owner
Invitation to bid
Instructions to bidders
Bid form
Invitation to Bid
Advertises or otherwise notifies bidders of the proposed project
Instruction to Bidders
Provides potential bidders with an outline of how to formulate and submit their bid
Bid Form
Provides template for how bid information is to be conveyed to owner
Ledger
a component of a deck and is a board that supports joists and transfers loads from the deck to the structure to which the desk is attached
Level Spreader
Spillway
Riprap
Weir
Lumens
the total amount of light leaving a source, and as such, would be used in the design of a lighting plan to determine the relative amount of light that a given fixture would generate.
Detention facilities
used to hold runoff during storm events and release the storm water after a period of time - usually once the peak storm flow has passed.
Best used to reduce downstream flooding and erosion
Commonly employed stormwater management devices to improve water quality
Silt Fence
Water Quality Basin
Infiltration Basin
Perpendicular Offset Method
a layout system used in construction drawings.
Vertical Curve
Provides a transition between two slopes roadways, allow a vehicle to negotiate the elevation rate change at a gradual rate rather than a sharp cut
