SGH Bridge Crane Steel Inspection Report 052022.pdf

2 May 2022

Thomas P. Voorhees, LLA, RLA Associate\Project Manager Burns & McDonnell 10 North Park Place, Suite 330 Morristown, NJ 07960

Project 200726.02 – Condition Assessment of Bridge Crane Structures and Perimeter

Structural Streel Framing, Building 20, United States Army Arsenal, Watervliet, NY

Dear Mr. Voorhees:

At your request, Simpson Gumpertz & Heger Associates, Inc., P.C. (SGH) performed a condition assessment of the existing bridge crane structural steel supports and perimeter structural steel framing at Building 20 of the United States Army Arsenal in Watervliet, New York. This report summarizes our observations and provides recommendations for remedial needs.

1. BACKGROUND

We understand that Burns & McDonnell is currently engaged by the Department of Defense (DOD) to develop repairs for Building 20. You asked us to perform a visual survey of the support structures for the steel bridge cranes and the perimeter structural steel framing within the manufacturing area of the building to assess their condition and to recommend any necessary remedial repair work.

Building 20 is primarily a single-story, steel-framed manufacturing facility with exposed framing that was built in 1942. The Watervliet Arsenal facility, including Building 20, is listed on the National Register of Historic Places.

The building footprint is approximately 240 ft by 400 ft (roughly 115,000 sq ft) with a grid of interior columns spaced at 40 ft in each direction. Columns are spaced at 20 ft on-center along the perimeter walls of the building. The westernmost 40 ft of the building is primarily occupied by administrative offices and includes a second level. Within the manufacturing area, there are six column bays with steel bridge crane structures that travel in the east-west direction. The bridge cranes are supported on structural steel beams spanning between the steel building columns.

Thomas P. Voorhees, LLA, RLA - 2 - 2 May 2022

Project 200726.02

2. OBSERVATIONS

On 30 March 2022, Nathaniel B. Smith, P.E., Robert P. Antes, P.E., and Carly E. Lemchen of SGH visited Building 20 to observe and document the condition of the bridge crane supports, the perimeter structural steel framing, and the catwalk framing within the manufacturing area.

We performed our survey from the ground and from the accessible catwalks using cameras with zoom lenses. Our observations are summarized below. Approximate locations of observed distress are shown in Figure 1.

• The bridge cranes in each column bay travel along continuous crane rails supported on steel beams. The steel beams are supported by brackets attached to the column flanges to allow a continuous travel path for the bridge cranes. The interior columns support two parallel steel beams; one on each side of the columns. Steel channel struts are installed between the webs of the parallel beams and horizontal cross bracing consisting of steel angles is installed between the top flanges.

• The steel trusses along the exterior of the building include double angle top chords and steel channel bottom chords with steel double angle diagonal and vertical members. The top and bottom chords frame into the flanges of the perimeter building columns.

• We observed corrosion staining and missing/flaking paint on the structural steel around the perimeter of the building adjacent to existing roof drains. We observed these conditions on the cross ties, spandrel beams, bottom chords of the trusses, and on the columns (Photos 1 – 4). We also observed corrosion staining and missing/flaking paint at several interior columns and structural members adjacent to existing roof drains (Photos 5).

• We observed grease staining in numerous locations along the top flanges of the crane support beams (Photo 6). In addition, we observed grease staining at some column splice connections, beam webs, and steel channel struts (Photos 7 and 8).

• We observed flaking paint at discrete locations on the top flange of the crane support beams around the building (Photo 9). At the southwest corner of the building, there is a vertical double angle cross brace and we observed corrosion staining along the horizontal legs of the angles.

• At two locations (Column Line E between Column Lines 9 and 10 and Column Line F between Column Lines 9 and 10; Figure 1), we observed bent channel struts spanning between the crane support beams (Photos 10 and 11).

Thomas P. Voorhees, LLA, RLA - 3 - 2 May 2022

• Catwalks are located along the tops of the crane support beams at the east and west ends of Column Lines B, D, and F. The catwalks are accessible by two vertical fixed ladders; the first ladder provides access from floor level to a small intermediate platform hung from the underside of the crane beams and the second ladder provides access from the intermediate platform to the catwalk on top of the crane beams. The intermediate platforms are typically constructed of steel channels spanning between supports at the column and hangers from the crane beams and open metal grid decking spans between the members. At the catwalk level, the open grid decking spans between the crane beams. The platforms and catwalks are enclosed with a metal guardrail system with wire mesh infill. Swing gates along the guardrails allow access from the catwalks to the cranes. We observed the following conditions at the catwalks:

• At the catwalk on Column Line D between Column Lines 9 and 10, we observed deformation of the vertical bars of the ladder between the floor and the access platform and a hole in the metal wire mesh along the sides of the catwalk (Photos 12 and 13).

• At the catwalk on Column Line F between Column Lines 6 and 7, the posts for the guardrail along the top of the crane support beams were bent and leaning away from the platform. The end of the catwalk was open with caution tape across the platform and the guardrail was incomplete (Photos 14 and 15).

• At the catwalk on column line F between column lines 1 and 2, one of the latches for the gate to access the crane was broken.

• At the catwalk on Column Line D between Column Lines 1 and 2, we observed a section of missing wire mesh between guard posts and a missing gate (Photos 16 and 17).

3. DISCUSSION AND RECOMMENDATIONS

The steel framing at Building 20 is located within the building enclosure (exterior walls and roof) and is generally protected from weather exposure. When water penetrates the building enclosure, exposed steel is at risk of corrosion. Corrosion can occur when bare steel is exposed to water and oxygen. The corrosion can reduce the available cross-section of the steel reducing the capacity of the structural member.

In general, the steel framing around the exterior of the building and supporting the bridge crane structures appears to be in good condition and we observed isolated locations of likely corrosion at or near locations of apparent leakage. Based on our limited observations, most of the corrosion appears relatively minor with a few isolated locations with more severe corrosion.

The minor corrosion that we observed was mostly present at areas along the exterior walls and

Thomas P. Voorhees, LLA, RLA - 4 - 2 May 2022 existing roof drains. The more severe corrosion that we observed was concentrated at areas immediately adjacent to existing roof drains. During our investigation, we were unable to observe the corrosion up close due to limited access and we were unable to determine if there is any section loss that would affect the capacity of the corroded structural members. We recommend that any corrosion product is removed and the steel cleaned to bare metal. Once the corrosion is removed, the steel should be inspected to determine if any significant section loss has occurred and if any structural remedial work is required. If structural repair is not required, the steel should be painted to protect it against future corrosion. A suitable corrosion-inhibiting paint should be specified and the paint should be compatible with potential exposures in the building. In addition, we recommend that the source of any leakage, especially at the existing roof drains and the exterior walls, be addressed to mitigate water infiltration and prevent future corrosion.

The bent channel struts spanning between the crane beams are intended to brace the beams to prevent lateral displacement. The bent channel struts between Column Lines 9 and 10 are deformed, which may affect the performance of the structure supporting the crane rails.

However, there is no visible cracking in the paint to suggest that the members are fractured.

The bent members have likely been in service for some time and it is not clear that they are affecting operation of the cranes. However, replacing or supplementing the members should be considered.

The catwalks are in generally good condition except for a few isolated locations. The vertical bars of the ladder to access one of the catwalks are bent, but all of the connections and components are intact. The ladder could be replaced but it currently appears to be structurally stable. In addition, one of the latches for a gate to access the crane is broken. We recommend that this condition be repaired to ensure the gate will not swing out and to allow safe access to this catwalk. Additionally, there is a missing gate and missing wire mesh panel at one of the catwalks. We recommend that the gate and wire mesh panel be replaced to allow safe access to this catwalk.

The guardrail of the catwalk along Column Line F between Column Lines 6 and 7 is deformed and appears to have been previously impacted. In addition, the guard posts in that area appear inadequate and incomplete. We recommend that the guardrail systems be replaced, and the guardrail system be completed to allow safe access to this catwalk.

Thomas P. Voorhees, LLA, RLA - 5 - 2 May 2022

4. CONCLUSIONS

Based on our observations, we conclude the following:

• The majority of the existing bridge crane structural steel supports and the perimeter structural steel framing at Building 20 is in generally good condition and had no observable distress. We observed two bent channel struts between the crane beams between Column Lines 9 and 10, which may need to be replaced.

• Several structural members adjacent to roof drain locations and along the exterior walls are corroded and should be maintained/repaired through typical steel cleaning techniques prior to coating with protective paint. The steel should be inspected after corrosion product is removed to determine if additional repairs are necessary.

• The guardrails along the catwalks have isolated damage that result in safety concerns.

These conditions should be remediated to allow safe access to the catwalks.

Alternatively, if the catwalks are not being used, consideration should be given to removing them.

Sincerely yours, Nathaniel B. Smith, P.E.

Principal NY License No. 086542 I:\NY\Projects\2020\200726.02-CRNR\WP\001NBSmith-L-200726.02.st.docx

Encls.

SGH Project 200726.02 / March 2022

Photo 1

Corrosion staining on cross tie rods at south wall of building.

Photo 2

Corrosion staining on underside of spandrel beam at south wall of building.

Photo 3

Corrosion staining and flaking pant on bottom chord of truss at south wall of building.

Photo 4

Corrosion staining and flaking paint at steel column adjacent to roof drain at south wall of building.

Photo 5

Corrosion staining at steel Column C4 adjacent to roof drain.

Photo 6

Grease staining on top flange of crane beam at Grid Line E.

Photo 7

Grease/water staining at column splice at Column C2.

Photo 8

Grease/water staining on flange, web, and strut at column C2.

Photo 9

Flaking paint at top flange of crane beam on Grid Line C.

Photo 10

Bent channel strut at Column Line E between Column Lines 9 and 10.

Photo 11

Bent channel strut at Column Line F between Column Lines 9 and 10.

Photo 12

Bent vertical bars at ladder to access catwalk at Column D10.

Photo 13

Hole in wire mesh fence along side of catwalk adjacent to Column D10.

Photo 14

The guard post is bent/deformed and leaning away from the catwalk along Column Line F between Column Lines 6 and 7.

Photo 15

Bent and deformed metal frame installed at the end of the catwalk platform along Column Line F between Column Lines 6 and 7. Note the guards do not extend beyond the ladder handles.

Photo 16

Missing wire mesh panel at the catwalk along Column Line D between Column Lines 1 and 2.

Photo 17

Missing guard section along the catwalk on Column Line D between Column Lines 1 and 2.

Figure 1 Summary of field notes depicting locations of corrosion and other distress.