Harlow HotelPortland, OR

Harlow Hotel

• Technical Information

• Project Completion Date: 08/17/2019

• Project Location: Portland, OR

• Size of Project: 14,000-sf

• Strength Requirements: 3,700 psi to 4,000 psi

• Water/Cement Ratio(s): .0470 for the interior slab-on-grade; .487 for select columns and beams; .421 for select columns and beams

• Unique or High Volume Admixtures: Full range WR; MRWR; ASTM C-494 Water Reducer; Stabilizer; VMA; ASTM C-494 F HRWRA; ASTM C-494 Type A WRA

Harlow Hotel

• Describe unique mix designs: Standard self-consolidating concrete was placed for the project. No concrete vibrating equipment was used during the construction process.

• Describe unique specifications/requirements (flatness, color, etc.): Constructing a concrete moment frame to an existing unreinforced masonry building is not a typical reinforcement solution. For this project, the owner wanted to maintain the storefront aesthetic and overall architectural facade without installing brace frames. Therefore, a concrete moment system on the Glisan Street side was the best application. More than 100,000-lbs of rebar was installed and more than 450 yards of concrete was poured for the renovation project.

• Describe placement challenges or unique techniques: The project team installed a new elevator shaft comprised of cast-in-place concrete walls, which required more effort with the concrete formwork. The rebar cages were tightly arranged with minimal clearance, making the concrete pour tricky (concrete hose couldn't be inserted through the rebar for easy removal). The elevator's concrete core acts as a global strengthening component. At the bottom of the elevator pit is a 45-yard concrete footing anchoring the elevator shaft and the building.

• Describe other special technical aspects:

Harlow Hotel

The new main entrance of Harlow Hotel.

Harlow Hotel

The Harlow Hotel in Portland’s Pearl District was originally built in 1882. Under recent new ownership, the three-story unreinforced masonry (URM) building has been renovated and reopened this year as a 25-key boutique hotel. The hotel now has a penthouse level and ground floor retail spaces ranging from 500-sf to 1,500-sf. The engineers conducted a seismic assessment of the building and determined

how to strengthen the building’s lateral and gravity systems to current codes with concrete solutions.

Harlow Hotel

Harlow Hotel

Concrete was poured to create new shear walls and columns. Concrete forms were installed to make continuous formations from the basement to the second floor.

Harlow Hotel

A concrete moment frame was constructed for the first two tenant spaces. Using concrete moment frames on URM buildings is not a typical reinforcement solution. The building owner wanted to maintain the storefront look without brace frames, so a concrete moment

frame was the best application. A concrete box was formed in the basement for above concrete columns to sit on.

Harlow Hotel

A concrete elevator core was selected as a better choice than steel for making the core an integral lateral element of the building. The rebar cage forming the elevator shaft required more formwork effort from the GC. At the bottom of the elevator pit is a 45 yard concrete

footing to anchor the building.

Harlow Hotel

In the basement, 10-inch thick concrete walls were formed to accommodate the steel framing installed above. Concrete was also poured against basalt walls.

Harlow Hotel

The refurbished grand stairway.

Harlow Hotel

The refreshed lobby

Harlow Hotel

An executive king room