Notes & Math Review Exam 1

How big is construction?

2022 Construction Spending: $1.8 trillion

US GDP (2022): $25.72 trillion (7% of GDP from construction)

Employment:Total Construction

Employment: 7.77 million (2.3% of US population)Projected

Employment by 2028: 8.10 million (2.4% of projected US population)

Number of Companies: Over 745,000 companies in the construction sector

Hand Take Off

Involves quantifying materials by hand using drawings, specifications, and other documents.

Tools of Hand Take Off

Specifications: Define requirements for products/materials/workmanship.

Plans: Drawings in PDF or TIFF format for accurate reference.

Addendums: Latest modifications from the architect.

Colored Pencils: To highlight and quantify items.

Columnar Pad/Spreadsheet: Organize numbers systematically.

Scoping: Define why you are quantifying (impacts overall estimating).

How do you eat an elephant

One bite at a time." Break down the estimating process into manageable components.

Scope

Elements or trade to quantify

Elements make up the trade (piers, grade beams, reinforcing steel)

Trades: steel, masonry, concrete.

Each trade has a set of elements they focus on

Specifications

Documents that define the qualitative requirement for products, materials, and workmanship upon which the contract for construction is based

Descriptions of elements (describes the product)

Level of quality or finish of elements

Divided by the CSI Master Format that organizes construction information

Drawings

Graphics illustrations depicting the dimensions, design, and location of a project.

Generally including plans, elevations, details, diagrams, and sections

Used to determine the location and extent of elements. Provides the information required to quantify elements

Addenda, Addendums, Change Requests, ASI's

Provides additional detail, information or modify the specifications or drawings

Relates to IFB or contract documents (in the bidding phase and what you are contracted for)

Contract Documents

The legally binding agreements that outline price, scope, unit of measure, and quantities.

Always refer to contract documents for accuracy, as written agreements supersede oral agreements.

Procurement phase of contract documents

Hard bid/ Lump sum: single fixed price for the entire scope of work

Competitive simple proposal: a competitive proposal where price is considered but also experience, schedule and past performance

David Bacon wage: clause that determines the minimum amount to pay employees.

Geotechnical Report

A report about:

Site visit where multiple bores are down to get soil samples. Test the soil samples to get bearing capacity.

Determines the sub soils and what foundation systems will work.

Sometimes in contract (if not in contract, owner is responsible for price)

Reactive soils

Reactive soil is soil that shrinks and swells. You have to isolate the structure from the soil so the soil can shrink and swell without damaging the structure.

Potential vertical movement is from the movement of the soil as it shrinks and swells vertically

Safety by a factor of 3

The structure is designed to withstand three times the expected load or stress it will experience in normal use.

Lime stabilization

A soil treatment for clay rich soils. It improves the strength, durability and workability of the soil. Plasticity reduction and reduction in moisture holding capacity

Storm Drainage

Water released at many levels

Notify Texas Commission on Environmental Quality when eacting SWPPP.

Have to control the release of dirt on the site

Notify the TCEQ and get a notice of intent when you disturb soul in a new site (AHJ if not in Texas)

NOT (Notice of termination) once finished with distrubance. Get this after the NOI and securing the site. Can't get unless regular grass is growing and has had 1 cut.

NOT is needed for final completion, substantial completion is granted though

Cut and Fill

Earth which is removed (cut) and earth which is added (fill) in grading.

Top soil is always removed due to the unstable organics (save for after done for plants)

One site plan, dark lines are existing and light are proposed. Have to pay attention to elevation lines.

States of Consistancy of Soil

From lowest to highest water content:

Solid state: crumbles

Semi-Solid State: pottery clay

Plastic state: plastic state, moldable and holds shape like playdough

Liquid State: levels back out

As moisture is added clay swells and sand shrinks

Board forms are used under places to keep it off the fluctuating ground volume. Have to isolate the soil

Capillary water barrier

A layer (often gravel) placed below the foundation to prevent moisture from rising into the slab.

This is especially important in wet areas to reduce water-related foundation issues.

Typical foundation layer order from top down

Slab (Minimum 4")

Gravel base course (drainage)

Compacted fill (compacted to 95% density)

Void forms

cardboard, as the concrete sets they get moisture and collapse leaving the space

Slabs made with slab on void still needs to be compacted to deter differential settling, uniform packing

Foundation requirements

Density has to be 95%, fill the area in layers, and compact it into 6" intervals

Foundation systems

4 Most common:

Spread/spot footings (shallow) (10ft to surface)

Mat foundations (large massive foundation, under skyscrapers)

Pile foundations (steel, timber pile in ground w/ foundation on top)

Drilled shafts

Spread and Continuous Footings (Shallow)

Less than 10ft deep

Spot footing will be a square

continuous footing can be in form (CMU wall on top)

neat/earthform is a continuous footing without a form

Mat Foundations

Add all the loads on top, a massive block of concrete

Used to load large columns and skyscrapers

1000s of cy of concrete with rebar

High, tall, heavy buildings

No differential settlement

Pile Foundations

Transfer heavy loads to underlying strata that is too deep to utilize

spread footings or mat foundations

Going very deep

Timber piles work by friction in the soil

Pile down to a rock or rock like structure

Drilled Shafts

Drilled shafts are a cast in place foundations which distribute loads through skin friction or bearing. May be belled or straight

Transfer loads from the surface to a deeper strata

Most economical types of support system

Transmit the load to a rock or rock like strata below

Most common type

Auger piles. Burrow hole and fill with grout as pull up and put in rebar, different from drilled shafts

Spoil

the material removed from a drilled pier or excess material removed from a grade beam

Clear cover

space between reinforcing steel and dirt

Unless Noted Otherwise (UNO)

If it shows in the drawing do it like the drawing, if not default back to what it said in notes.

Ties/ Stirrup

used to hold the long bars in a specific location within the structural area

Ties wire is to hold the steel until concrete hardens

Penetration

How deep the shafts go into the bearing stratum

Reinforcing Steel

On steel top is mark ribs, middle is bar size, bottom is type of steel, if grade 60 it will be labeled

Deformed bar, concrete is able to grab ahold

In the U.S. bars are designated by 8ths an inch

Rebar erector, someone who installs rebar

Steel as it is stressed stretches until it is snapped

Based on gauge

Lap bars

Overlapping of rebar. Lower grade has shorter lap, higher grade longer lap

Conversions

Inch to Foot: 12" = 1'

Square Foot to Square Yard: Square Ft/9

Cubic Feet to Cubic Yard: Cubic Feet/27

1 sq ft = 144 sq in

Division and Multiplication of Fractions

Division: Keep change Flip

Multiplication: Multiply accross

SIMPLIFY

Areas

Rectangular: L*W

Triangle: 1/2 bh

Circle: pi r^2

Volume

LWH

Assignment 1

Specs search and find

Assignment 2 (Elevations)

Find sub grade which is the FF - slab and form

Establish the area you are working with in SF

Distance between the bottom elevation and the corner of the grid over the distance between the 2 elevations above and below corner point. Get decimal and add it to the bottom elevation to get the elevation of the corner.

Do it for each corner of the grid square. Add them up and divide by 4 to get the existing grade.

Take the difference between the sub grade and the existing grade to get a cut (-) or a fill (+)

Find volume by multiplying result by the established sf area to get CF, then divide by 27 to get CY.

Assignment 3a (Straight Shaft Piers)

Find and label all the piers.

Tk the top of the pier subtract 65 (strata) and then add 20 (penetration) to get the length of the pier.

Overburden: top of slab (100) - thickness of slab (in inches) then subtract the top of pier.

Reinforcing: length of pier that was calculated in pt.1 minus 0.417 to get length of long bar.

Number of stirrups: length of long bars divided by spacing of stirrups (o.c.) round up and add 2.

Length of each stirrup: Diameter of pier - clear cover (each side so times 2), convert to ft then multiply by pi. then add 1.375 to get total length of stirrup with lap.

Dowels: Bar diameter * 6 divided by 8 convert to ft. If there is a hook add 0.75.

Assignment 3b (Bell Pier)

Length of Pier: Top of pier subtract 80

Overburden: 100 - thickness of slab and carton form subtract top of pier.

Reinforcing: Length of puer -0.25 - 0.167 to get length of long bars

Number of Stirrups: Length of pier reinforcing cage divided by o.c. round up and add 2.

Length of each tie: diameter of pier - 6 convert to ft and multiply by pi. add 1.375 to get total length of stirrup with lap

Dowels: length of dowel and if hook add 0.75