Skip to contentUnited States Department of Transportation - Federal Highway Administration Go to TFHRC homeGo to FHWA websiteFeedback

Figure 26. Type 4 stiffness control reduces hourglassing better than type 3 viscous control. Diagrams A and B.

  1. 120-millimeter deflection, Viscous control.

    This figure shows a closeup of a rectangular structure. The surface of this structure is broken down into rows and columns of small squares. The structure is roughly 18 rows high and eight columns wide. The top and bottom halves of the entire structure are colored a dull pink while the center of the structure is colored a dark red. The top half of the structure is tipped backward slightly, the first two squares in the first two columns at about the center point of the structure are missing, the remaining row of squares at center point squished as a result of the tipping top.120-millimeter deflection, Stiffness control. This figure shows a closeup of a rectangular structure. The surface of this structure is broken down into rows and columns of small squares. The structure is roughly 18 rows high and eight columns wide. The top and bottom halves of the entire structure are colored a dull pink while the center of the structure is colored a dark red. The top half of the structure is tipped backward slightly, the first four squares in the first four columns at about the center point of the structure are missing, the remaining row of squares at center point squished as a result of the tipping top.

    120-millimeter deflection, Fully integrated S/R.

    This figure shows a closeup of a rectangular structure. The surface of this structure is broken down into rows and columns of small squares. The structure is roughly 18 rows high and eight columns wide. The top and bottom halves of the entire structure are colored a dull pink while the center of the structure is colored a dark red. The top half of the structure is tipped backward slightly, the first four squares in the first four columns at about the center point of the structure are missing, the remaining row of squares at center point squished as a result of the tipping top.

  2. 190-millimeter deflection, Viscous control.

    This figure shows a rectangular structure broken into rows and columns of small squares. The structure is roughly 42 rows high and eight columns wide. The majority of the structure is colored a dull pink with the exception of eight by six section colored in dark purple with an eye hook protruding from the right hand side and an eight by eleven section at the very bottom of the structure colored a dark red. Row six in the red section of the rectangle is missing its first two squares on the left hand side, while the next two squares are jagged and rough. The remaining squares in that row are squished as the top of the rectangle is tilted to the right, tearing those two squares from their original state.

    190-millimeter deflection, Stiffness control.

    This figure shows a rectangular structure broken into rows and columns of small squares. The structure is roughly 42 rows high and eight columns wide. The majority of the structure is colored a dull pink with the exception of eight by six section colored in dark purple with an eye hook protruding from the right hand side and an eight by eleven section at the very bottom of the structure colored a dark red. Row six in the red section of the rectangle is missing its first five squares on the left hand side, while the remaining three in that row are squished as the top of the rectangle is tilted to the right, tearing those two squares from their original state.

    190-millimeter deflection, fully integrated S/R.

    This figure shows a rectangular structure broken into rows and columns of small squares. The structure is roughly 42 rows high and eight columns wide. The majority of the structure is colored a dull pink with the exception of eight by six section colored in dark purple with an eye hook protruding from the right hand side and an eight by eleven section at the very bottom of the structure colored a dark red. The first five squares in row six of the red section have torn away from the squares that sat upon while the following three squares one row down have torn away from the squares they once sat on as the top of the rectangle tilts to the right.

Return to Report

FHWA-HRT-05-096


TFHRC Home | FHWA Home | Feedback
FHWA