Pavement Engineering Inc. Services

Deflection Testing Services

All our field testing is performed with safety in mind. We provide traffic control during testing using a trailer-mounted arrow board with appropriate signs and flagmen where necessary.

Deflection testing

PEI uses the Dynaflect to perform deflection testing. Dynaflect measures a pavement’s structural properties by applying an oscillating load on the pavement and measuring the resulting deflection. Pavement Engineering’s deflection testing conforms to California Test Method 356.

The Dynaflect is a dynamic-force generator and motion-sensing device, mounted on a small trailer, that produces a vertical force varying sinusoidally at the rate of eight cycles per second. It measures deflections when the trailer stops at the desired location and a motion-sensing device lowered to the pavement surface reads the deflection data.

The total force applied to the surface beneath the Dynaflect trailer consists of the static weight of the apparatus (2,000 pounds), plus the dynamic force, which alternately adds to and subtracts from this weight. The peak-to-peak excursion of the dynamic force is 1,000 pounds, which is applied to the ground through a pair of rigid wheels.

Core testing

Core testing measures existing pavement thicknesses to determine pavement structural capacity. Used in conjunction with Dynaflect testing and visual observations of current cracking conditions and roadside draining, core testing provides the necessary data to provide sound repair or maintenance recommendations.

In addition to Dynaflect and core testing, we review traffic patterns to verify the accuracy of traffic indexes. We can perform classified truck counts where necessary to determine these indexes.

Once our testing is complete, Pavement Engineering issues a report with our analysis and recommendations.