Hopewell City Marina Stuctural Observation Blue Nest Structural 6-1-23.pdf

BLUE NEST

STRUCTURAL

313 E Broad St; Suite 322

Richmond, Virginia

804.409.6272

June 1, 2023

City of Hopewell, VA Parks and Recreation 100 W. City Point Road Hopewell, Virginia 23860 Attn: Tom Gate

Reference: Hopewell City Marina – Structural Observations 1051 Riverside Ave, Hopewell, VA 23860 Blue Nest Project #: R23.074

Dear Tom:

I visited the Hopewell City Marina in Hopewell, Virginia, on Thursday, May 11th, 2023, to observe the structural condition of 3 separate docks. The “L” and “N” docks are covered by a roof structure, and the “M” dock does not have any structure covering the dock. The docks are constructed of wood decking atop wood stringers, supported by wood girder beams on wood piles that extend into the water. The roof structures consist of an Onduline roofing, supported by wood purlins, wood joists and wood girders. The wood girders frame into wood trusses that bear on wood piles. The photo below shows the locations of the three docks:

Observations:

During the site visit, I was able to observe the roof framing, the wood piles, and the portions of the dock structure above the water. The observations were limited to the visible portions of the structure, nothing below the surface of the water was observed, and no testing or analysis was provided.

There were several structural issues throughout the docks, with the “L” Dock showing the most visible damage. Some of the structural issues that were more serious have been repaired and/or temporarily shored. Below is a list of specific issues and where they occur:

1. There is severe damage to the Onduline roof deck throughout the roof of the “L” dock. One bay has enough damage that a tarp has been put up to protect the boats below from falling roof material (figures 1 and 2).

2. A column at the edge of one of the roof trusses of the “L” Dock is missing and a wood brace to an adjacent column has been installed (figure 3).

L

3. At the front of the “L” Dock, there is damage to the wood members supporting the canopy, one member has failed, and others show significant deflection (figures 4 and 5).

4. Many of the wood truss panel points in both the “L” Dock and the “N” dock are not centered on the wood posts

(figure 6).

5. At one location in the “L” Dock, the wood girder beam has been replaced with new lumber with the same geometry as the existing but likely less strength and is missing uplift ties at every other beam (figure 7)

6. At multiple locations in the “L” Dock, the wood roof trusses show noticeable deflection (figure 8).

7. At one location in the “L” Dock, the roof truss bottom chord has noticeable section loss at the bearing location

(figure 9).

8. One column that supports the gable end truss at the back of the “L” Dock has had significant section loss, and adjacent members have been reinforced to support the truss, which has led to some deflections (figures 10 and 11).

9. The wood members that are submerged in water at all three docks appear to show signs of damage from the prolonged exposure to water. Some of the posts have noticeable section loss at and below the high-water level, some of the girder beams supporting the stringers have split, and some of the wood decking is rotting (figures 12, 13 and 14).

Figure 1: Typical damage at Oduline Roof Figure 2: Tarp at damaged roof

Figure 3: Missing column with temporary brace Figure 4: Failed member supporting canopy

Figure 5: Member supporting canopy deflecting Figure 6: Truss misaligned with pile

Figure 7: New girder missing uplift ties Figure 8: Wood roof truss deflecting

Figure 9: Section loss at bearing point Figure 10: Section loss at column

Figure 11: Deflection due to column section loss Figure 12: Section loss at column below water level

Figure 13: Wood girder beam splitting Figure 14: Damage to wood dock due to water exposure

Conclusion

The repairs to all three of the docks would be classified as level 1 alterations according to the International Existing Building

Code (IEBC). The damage to the roof deck in the “L” Dock is substantial throughout, and the damage has increased the exposure of the structural elements supporting the roof. This increased exposure is causing the structural elements to deteriorate more quickly. All of the structural damage can be classified as less than substantial structural damage and is permitted to be repaired to its original capacity according to the IEBC.

Fig. 10

Based on the observations described above, there are issues throughout the docks that will need to be repaired. Most of the issues are minor to moderate and should be straightforward to repair. The roof deck of the “L” Dock should be replaced with a lightweight roof material, such as corrugated metal roofing, that is resistant to water exposure. The new roof deck weight should be limited so it increases the loads on the structure by no more than 5%. The most notable structural issue is the missing column at the “L” Dock. The missing column must be replaced. The column in the “L” Dock shown in figure 10 must also be repaired. The main wood piles were only observed above the water level at the time of the observations, however, given the damage observed to the girders and stringers supporting the dock slats that appears to be caused by the long-term exposure to water, the main piles should be more thoroughly observed, specifically below the water level. If any piles are observed to have significant section loss of greater than 20%, they must be repaired. Similarly, any wood girders or stringers supporting the wood dock that have more than 20% section loss must be repaired. Any wood girders or stringers supporting the deck that have split at the connection, similar to what is shown in figure 13, must be replaced. The member at the front canopy on the “L” dock shown in figure 4 and 5 must be replaced, and any members that have been damaged to a similar extent must also be replaced. Lastly, many of the wood columns are not directly below panel points on the wood trusses. This can lead to unintended stress along the bottom chord of the wood trusses, which could lead to member failure. Connections should be added connecting the wood trusses to the columns to ensure the trusses stay aligned and to help resist uplift caused by wind acting on the roof.

Chris Folsom, E.I.T.

Engineer-In-Training

Garrett Braun, P.E.

Principal