Reclaimed Fly Ash as Select Fill Under PCC Pavement

Reclaimed Fly Ash as Select Fill Under PCC Pavement PDF Author: Kenneth L. Bergeson
Publisher:
ISBN:
Category : Fills (Earthwork)
Languages : en
Pages : 76

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Book Description
With the support of the Iowa Fly Ash Affiliates, research on reclaimed fly ash for use as a construction material has been ongoing since 1991. The material exhibits engineering properties similar to those of soft limestone or sandstone and a lightweight aggregate. It is unique in that it is rich in calcium, silica, and aluminum and exhibits pozzolanic properties (i.e. gains strength over time) when used untreated or when a calcium activator is added. Reclaimed Class C fly ashes have been successfully used as a base material on a variety of construction projects in southern and western Iowa. A pavement design guide has been developed with the support of the Iowa Fly Ash Affiliates. Soils in Iowa generally rate fair to poor as subgrade soils for paving projects. This is especially true in the southern quarter of the state and for many areas of eastern and western Iowa. Many of the soil types encountered for highway projects are unsuitable soils under the current Iowa DOT specifications. The bulk of the remaining soils are Class 10 soils. Select soils for use directly under the pavement are often difficult to find on a project, and in many instances are economically unavailable. This was the case for a 4.43-mile grading (STP-S- 90(22)-SE-90) and paving project in Wapello County. The project begins at the Alliant Utilities generating station in Chillicothe, Iowa, and runs west to the Monroe-Wapello county line. This road carries a significant amount of truck traffic hauling coal from the generating station to the Cargill corn processing plant in Eddyville, Iowa. The proposed 10-inch Portland Cement Concrete (PCC) pavement was for construction directly on a Class 10 soil subgrade, which is not a desirable condition if other alternatives are available. Wapello County Engineer Wendell Folkerts supported the use of reclaimed fly ash for a portion of the project. Construction of about three miles of the project was accomplished using 10 inches of reclaimed fly ash as a select fill beneath the PCC slab. The remaining mile was constructed according to the original design to be used as a control section for performance monitoring. The project was graded during the summers of 1998 and 1999. Paving was completed in the fall of 1999. This report presents the results of design considerations and laboratory and field testing results during construction. Recommendations for use of reclaimed fly ash as a select fill are also presented.

Reclaimed Fly Ash as Select Fill Under PCC Pavement

Reclaimed Fly Ash as Select Fill Under PCC Pavement PDF Author: Kenneth L. Bergeson
Publisher:
ISBN:
Category : Fills (Earthwork)
Languages : en
Pages : 76

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Book Description
With the support of the Iowa Fly Ash Affiliates, research on reclaimed fly ash for use as a construction material has been ongoing since 1991. The material exhibits engineering properties similar to those of soft limestone or sandstone and a lightweight aggregate. It is unique in that it is rich in calcium, silica, and aluminum and exhibits pozzolanic properties (i.e. gains strength over time) when used untreated or when a calcium activator is added. Reclaimed Class C fly ashes have been successfully used as a base material on a variety of construction projects in southern and western Iowa. A pavement design guide has been developed with the support of the Iowa Fly Ash Affiliates. Soils in Iowa generally rate fair to poor as subgrade soils for paving projects. This is especially true in the southern quarter of the state and for many areas of eastern and western Iowa. Many of the soil types encountered for highway projects are unsuitable soils under the current Iowa DOT specifications. The bulk of the remaining soils are Class 10 soils. Select soils for use directly under the pavement are often difficult to find on a project, and in many instances are economically unavailable. This was the case for a 4.43-mile grading (STP-S- 90(22)-SE-90) and paving project in Wapello County. The project begins at the Alliant Utilities generating station in Chillicothe, Iowa, and runs west to the Monroe-Wapello county line. This road carries a significant amount of truck traffic hauling coal from the generating station to the Cargill corn processing plant in Eddyville, Iowa. The proposed 10-inch Portland Cement Concrete (PCC) pavement was for construction directly on a Class 10 soil subgrade, which is not a desirable condition if other alternatives are available. Wapello County Engineer Wendell Folkerts supported the use of reclaimed fly ash for a portion of the project. Construction of about three miles of the project was accomplished using 10 inches of reclaimed fly ash as a select fill beneath the PCC slab. The remaining mile was constructed according to the original design to be used as a control section for performance monitoring. The project was graded during the summers of 1998 and 1999. Paving was completed in the fall of 1999. This report presents the results of design considerations and laboratory and field testing results during construction. Recommendations for use of reclaimed fly ash as a select fill are also presented.

Field Demonstration Project

Field Demonstration Project PDF Author: Kenneth L. Bergeson
Publisher:
ISBN:
Category : Fills (Earthwork)
Languages : en
Pages : 63

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Book Description
With the support of the Iowa Fly Ash Affiliates, research on reclaimed fly ash for use as a construction material has been on going since 1991. The material exhibits engineering properties similar to those of soft limestone and a lightweight aggregate. It is unique in that it is rich in calcium, silica, and aluminum and exhibits pozzolanic properties (i.e. gains strength over time) when used untreated or when a calcium activator is added. Reclaimed Class C fly ashes have been successfully used as a base material on a variety of constructions projects in southern and western Iowa. A pavement thickness design guide has been developed with the support of the Affiliates. A cement kiln dust activated reclaimed hydrated Class C fly ash (C-Stone) was used as a base material for construction of a half-mile test road near Ottumwa in 1995. This road consisted of an eleven-inch calcium activated reclaimed ash base and a fly ash stabilized subgrade with a 1 to 1-1/2 inch asphalt surface course. This road carries semi-truck traffic to the Ottumwa Midland Landfill. It has been and is performing very well. A test road was also constructed in 1994 in Marshalltown at the Sutherland Power Plant. It is an access road to the power plant with an eleven-inch calcium activated C-Stone base and a double sealcoat surface. It also has been performing well. Research needs to be conducted using these materials in an untreated condition.

Reclaimed Class C Iowa Fly Ash as a Select Fill Material

Reclaimed Class C Iowa Fly Ash as a Select Fill Material PDF Author: Daniel Brian Mahrt
Publisher:
ISBN:
Category :
Languages : en
Pages : 288

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Book Description
Research on reclaimed hydrated fly ash has been on going since 1991 with the support of the Iowa Fly Ash Affiliate Research Program. Costs associated with disposal of fly ash are increasing, and previous research has indicated that reclaimed Class C fly ash has beneficial uses in the construction industry. In most parts of Iowa, soils are of marginal to poor quality for use as subgrade soils in paving projects. Suitable soils for road construction are often not available, either geographically or economically. A grade-and-pave project near Chillicothe, Iowa (Wapello County, Iowa, project STP-S-90(22)-SE-90) was selected as a demonstration project utilizing reclaimed fly ash as a select fill because suitable soils for construction were not available in the area. Research and construction of reclaimed fly ash fill began on this project in October of 1998. Construction resumed in the spring of 1999, and placement of the select fill was completed in August of 1999. Paving of the project was completed in October of 1999.

Fly Ash Soil Stabilization for Non-uniform Subgrade Soils: Engineering properties and construction guidelines

Fly Ash Soil Stabilization for Non-uniform Subgrade Soils: Engineering properties and construction guidelines PDF Author:
Publisher:
ISBN:
Category : Fly ash
Languages : en
Pages : 182

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Book Description
Soil treated with self-cementing fly ash is increasingly being used in Iowa to stabilize pavement subgrades, but without a complete understanding of the short- and long-term behavior. To develop a broader understanding of fly ash engineering properties, mixtures of five different soil types, ranging from ML to CH, and several different fly ash sources (including hydrated and conditioned fly ashes) were evaluated.

An Introduction to Fly Ash in Concrete Pavement

An Introduction to Fly Ash in Concrete Pavement PDF Author: J. Paul Guyer, P.E., R.A.
Publisher: Guyer Partners
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 26

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Book Description
Introductory technical guidance for civil engineers interested in fly ash in portland cement concrete pavement for streets and highways. Here is what is discussed: 1. FLY ASH AS AN ENGINEERING MATERIAL 2. HIGHWAY APPLICATIONS 3. FLY ASH IN PORTLAND CEMENT CONCRETE.

The Use of Fly Ash in Highway Construction

The Use of Fly Ash in Highway Construction PDF Author: Vernon J. Marks
Publisher:
ISBN:
Category : Fly ash
Languages : en
Pages : 30

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Book Description
In 1982 the Iowa DOT allowed a successful bidder the option of submitting materials and proportions using fly ash to produce a portland cement concrete (PCC) paving mixture to meet a specified compressive strength. The contractor, Irving F. Jensen, received approval for the use of a concrete mixture utilizing 500 lbs. of portland cement and 88 lbs. of fly ash as a replacement of 88 lbs. of portland cement. The PCC mixture was utilized on the Muscatine County US 61 relocation bypass paved as project F-61-4(32)--20-70. A Class "C" fly ash obtained from the Chillicothe electric generating plant approximately 100 miles away was used in the project. This use of fly ash in lieu of portland cement resulted in a cost savings of $64,500 and an energy savings of approximately 16 billion BTU. The compressive strength of this PCC mixture option was very comparable to concrete mixtures produced without the use of fly ash. The pavement has been performing very well. The substitution of fly ash for 15% of the cement has been allowed as a contractor's option since 1984. Due to the cost savings, it has been used in almost all Iowa PCC paving since that time.

High Performance Concrete Pavements

High Performance Concrete Pavements PDF Author:
Publisher:
ISBN:
Category : Pavements, Concrete
Languages : en
Pages : 190

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Book Description


Fly Ash Soil Stabilization for Non-uniform Subgrade Soils: Influence of subgrade non-uniformity on PCC pavement performance

Fly Ash Soil Stabilization for Non-uniform Subgrade Soils: Influence of subgrade non-uniformity on PCC pavement performance PDF Author:
Publisher:
ISBN:
Category : Fly ash
Languages : en
Pages : 82

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Book Description
Soil treated with self-cementing fly ash is increasingly being used in Iowa to stabilize pavement subgrades, but without a complete understanding of the short- and long-term behavior. To develop a broader understanding of fly ash engineering properties, mixtures of five different soil types, ranging from ML to CH, and several different fly ash sources (including hydrated and conditioned fly ashes) were evaluated.

Use of Fly Ash in Soil-cement

Use of Fly Ash in Soil-cement PDF Author: Chester W. Jones
Publisher:
ISBN:
Category : Fly ash
Languages : en
Pages : 34

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Book Description


Fly Ash Soil Stabilization for Non-uniform Subgrade Soils

Fly Ash Soil Stabilization for Non-uniform Subgrade Soils PDF Author: David J. White (Ph. D.)
Publisher:
ISBN:
Category : Fly ash
Languages : en
Pages : 76

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Book Description
To provide insight into subgrade non-uniformity and its effects on pavement performance, this study investigated the influence of non-uniform subgrade support on pavement responses (stress and deflection) that affect pavement performance. Several reconstructed PCC pavement projects in Iowa were studied to document and evaluate the influence of subgrade/subbase non-uniformity on pavement performance. In situ field tests were performed at 12 sites to determine the subgrade/subbase engineering properties and develop a database of engineering parameter values for statistical and numerical analysis. Results of stiffness, moisture and density, strength, and soil classification were used to determine the spatial variability of a given property. Natural subgrade soils, fly ash-stabilized subgrade, reclaimed hydrated fly ash subbase, and granular subbase were studied. The influence of the spatial variability of subgrade/subbase on pavement performance was then evaluated by modeling the elastic properties of the pavement and subgrade using the ISLAB2000 finite element analysis program. A major conclusion from this study is that non-uniform subgrade/subbase stiffness increases localized deflections and causes principal stress concentrations in the pavement, which can lead to fatigue cracking and other types of pavement distresses. Field data show that hydrated fly ash, self-cementing fly ash-stabilized subgrade, and granular subbases exhibit lower variability than natural subgrade soils. Pavement life should be increased through the use of more uniform subgrade support. Subgrade/subbase construction in the future should consider uniformity as a key to long-term pavement performance.