
Martinsville, Virginia
Client: ASI Constructors
Owner: Natural Resources Conservation Service (NRCS)
At the time of the project, Marrowbone Dam No. 1 did not meet current dam design and safety criteria. Development in the floodplain and an increased risk to loss of life and property changed the classification of the dam from low hazard to high hazard. Rehabilitation was required, and included constructing an RCC spillway through the existing earth embankment; raising the top of the dam by 8.5 feet; and backfilling the existing emergency spillway to bring it to the same elevation as the new top of dam.
The emergency spillway and stilling basin construction project was designed by Schnabel Engineers and constructed by ASI Constructors.
Members of the Fall Line staff provided RCC mix designs performed to the standards of the NRSC as specified by Schnabel Engineers. The RCC mix design was a 15-second VeBe mix utilizing an aggregate base coarse material. Quality control services were also provided during the test phase of the project. Testing was performed to verify VeBe time of the mix and fresh unit weight, and to perform proof rolling patterns to establish in-place maximum density values. Compressive strength cylinders were also cast to verify the in-place RCC strengths in relation to the mix design.