concrete pavement construction the facts - ftba · 2013-01-09 · mechanistic empirical pavement...
TRANSCRIPT
2010 FDOT Construction Conference
Concrete Pavement
2010 FDOT Construction Conference
Concrete Pavement Construction – Just the Facts
Jamshid Armaghani Ph D PEJamshid Armaghani, Ph.D., P.E.
Florida Concrete and products Association
Concrete Pavements of TodayDesign –
Optimum and structurally soundEconomicalEconomical
Construction –Almost 100% automation F t d d i i l lFast and paved in a single layerSmooth Quiet
Quality –Innovative testing equipment to assure structural and functional qualityfunctional quality
Materials –Cement ‐ Locally produced i h h i d h bHigh strength concrete – New construction and Rehab
AASHTO Pavement Design GuideAASHTO Pavement Design Guide
• Empirical methodology based on AASHO Road Test in the late 1950’s
• Several versions:– 1961, 1972, 1986, 1993 (Empirical)M li i i– Many, many limitations
AASHO Road Test (late 1950’s)
(AASHO, 1961)
Limitations: Huge Traffic Extrapolation
Mechanistic Empirical Pavement Design Guide ( )(MEPDG)
State‐Of‐The‐Art Guide based on fundamental pavement engineeringpavement engineering principles, climatic conditions, traffic volumes & material characteristics. It has been calibrated using over 250 pavement sites pthroughout the country.
Climate
MEPDG
Traffic
Structure,Joints,
Traffic
DG Inputs Axle load (lb)
Materials & ConstructionReinforcement
DG Process
DG Outputs
stress
age Field Distress
8Damage
Dis
Distress Prediction & ReliabilityMechanistic Response
Damage AccumulationTime
Dam
MEPDG Design Optimization OptionsMEPDG Design Optimization Options Widened lanesSh t J i t iShort Joint spacing Larger size dowelsHi h i hHigher compressive strength Advantage of structural value of support layerslayersBond at Concrete‐asphalt base interfaceFl id Li t ith l C ffi i t fFlorida Limestone with low Coefficient of Thermal Expansion.
MEPDG Output king
% Crack
Slipform machine (2)
Curing/tining machine (3) Concrete Spreader (1)
Paving TrainPaving Train
Alignment Sensor
Elevation Sensor
Stringline
Leica System EquipmentLeica System Equipment
Computer on PaverComputer on Paver
Adjustable Telescopic Frame
Spreader arm
Tie bars basket Dowel bars basket
On‐site Batch Plant
Concrete mixes can be designed to allow opening lane to traffic from 6 hrs to 36 hours
Maturity Meter
Tie bars away from the Joint and ends of dowel bars
Nail dowel basket to AC baseto AC base
Transverse Tiningg
Wide tine spacing can be Noisy Narrow tine spacing (1/2”) produces quieter surface
Longitudinal Tines Produce quiet pavement q p
Grinding
Smoothness TestingSmoothness Testing
California Profilograph
Laser Profiler
Narrow Joints produce quiet pavement
Uncontrolled crack from delayed joint sawing
Narrow vs. Wide Joints
Narrow joints produce quieter pavement Joints > ½” Generate Noise
Joint too wide. Will cause noise.Must be ≤ ¼ “
Replacement slab
Pervious Concrete Edge Drain
Filter Fabric
Asphalt subbase
Graded aggregate gg gdrainage mat beneath curb.
Asphalt baseAsphalt base