Biomass Fly Ash in Concrete I

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					                                                                                        Biomass Fly Ash in Concrete I
                                                                                Shuangzhen Wang, Sharon Bragonje, Justin Tullis and Larry Baxter
Objective:                                                                                                                                                       Materials:
This investigation determines the effect of biomass fly ash in concrete    Coal: 1) class C and 2) class F 3) Wood: fly ash from pure wood
in a series of three posters on: 1) Concrete strength, durability, and the combustion and five co-fired biomass fly ash listed in the table
SEM scanning of pozzolanic reaction (I); 2) Strength build-up and          below:
quantitative kinetics of pozzolanic reaction (II); and 3) Mitigation of          Name        Coal       (%)                  Biomass        (%)

Alkali Silica Reaction (ASR) expansion (III). The overall conclusion is          SW1        Galatia      80                                  20
                                                                                             coal
that biomass fly ash’s performances are comparable to those                      SW2                     90      Cofired      Switch         10

of coal ash and should not be excluded from addition into                         10P
                                                                                           Powder
                                                                                                         90       With…        Grass         10

concrete.                                                                         20P        River       80                                  20
                                                                                Setting Time Test                                                                                     SAW
                                                                                                                                                                                                 Basin
                                                                                                                                                                                                                                80                                     Sawdust             20

                                    5000                                                                                                                                                    Rapid Chloride Permeability Test
                                                                                                                                                                               6000
Penetration Resistance (psi)




                                    4000
                                                                  Pure Cement                                                                                                  5000




                                                                                                                                                          Average (Coulombs)
                                                                  Class C
                                    3000                          Class F                                                                                                      4000
                                                                  SW1
                                                                  SW2                                                                                                          3000
                                    2000                          Wood
                                                                  Wood/C                                                                                                       2000
                                                                  Wood/F
                                    1000                                                                                                                                       1000

                                                                                                                                                                                 0     Cement   Class C                              SW 1
                                                                                                                                                                                                                      Class F                     SW 2         Wood           Wood C       Wood F
                                                     0
                                                         0        100         200       300          400          500        600       700          800                                                                                     Mix
                                                                                               Time (min)

                                                                  Compressive Strength Test                                                                          SEM & EMPA Scanning (SW1 Biomass Fly Ash)
                                                    45
                                                                                                                                                                                      (One year in concrete)                                                            Raw

                                                    40

                                                    35                                                                                       Cement
                                                                                                                                             Class C
                               Com pression (MPa)




                                                    30
                                                                                                                                             Class F
                                                    25                                                                                       SW1
                                                    20                                                                                       SW2
                                                                                                                                             Wood
                                                    15
                                                                                                                                             Wood C
                                                    10
                                                                                                                                             Wood F
                                                    5

                                                    0                                                                                                                                                                      Chemical analysis of SW1 fly ash particle
                                                              1         3           7         28           56           91     365
                                                                                                                                                                                                                1.8
                                                                                            Day
                                                                                                                                                                                                                1.6
                                                                                                                                                                                                                1.4
                                                                      Error bars indicate a 95% confidence interval                                                                                             1.2
                                                                                                                                                                                                  Ca/Si (mol)




                                                                                                                                                                                                                                                  Line A
                                                              Flexure Strength Test (56th day)                                                                                                                   1
                                                                                                                                                                                                                0.8
                                                                                                                                                                                                                                                  Line B

                                                    6                                                                                                                                                           0.6

                                                5.5
                                                                                                                                                                                                                0.4
                                                                                                                                                                                                                0.2
                                                    5
                                                                                                                                                                                                                 0
                                                4.5
                                                                                                                                                                                                                       1        2      3      4        5           6      7      8     9        10
                                                    4                                                                                                                                                                                                      Point
                                                3.5
                         MPa




                                                    3

                                                2.5

                                                    2

                                                1.5

                                                    1

                                                0.5

                                                    0
                                                             Cement   Class C     Class F     SW 1         SW 2     Wood      Wood C    Wood F                                           (one year in concrete)
                                                                                                     Mix
                                                                            Error bars indicate a 95% confidence interval