concrete repair

American Plaza Tower Condominium Parking Structure Repairs

Joint repair for American Plaza Parking Structure

Miller Consulting Engineers provided structural engineering services for this 200,000 square foot, four-level parking garage that serves residents of the American Plaza Condominium Towers in downtown Portland, Oregon. The garage was originally constructed in the early 1970s, and consists of a reinforced concrete waffle slab for the elevated levels of the structure. MCE was contacted to provide an assessment of the condition of the structure, as cracks were observed throughout many areas of the waffle slab and deterioration/corrosion was present in numerous areas of the slab.

The initial phase of MCE’s scope of services consisted of providing a visual observation of the garage, a preliminary review of the loading capacity of the structure, and a report outlining a recommended course of action to repair the structurally deficient areas.
American Slab AnalysisThe second phase of work consisted of MCE preparing a finite element analysis of the entire garage structure in order to more exactly identify areas that were overstressed. The finite element analysis allowed a precise measure of the structure’s load carrying capabilities, and thereby reduced the overall scope of structural upgrades. MCE also worked closely with a testing agency to outline areas of the building where non-destructive and destructive tests were needed in order to verify both the reinforcing steel in the slab and the compressive strength of the concrete. Additionally, MCE prepared an Engineer’s Opinion of Probable Construction Costs for the client to use in planning out the repair phases.
 Shoring and repairs of parking structure
The third and final phase consisted of preparing construction drawings for the structural upgrades, and providing construction administration services. Various upgrade and repair methods will be utilized to strengthen the structural elements, including the use of fiber reinforced polymers (FRP), conventional reinforcing steel, and repair mortars. This phase of the project is currently ongoing.

Rose City Storage

This 80,000 square foot, 4-story structure was originally constructed in 1920 with wood framed floors and concrete exterior walls.  The owner of the building has elected to renovate this old structure into a modern storage facility.  To achieve the vision and goals for this project set out by our client required strengthening measures be performed for the earthquake resisting elements, and the gravity load resisting elements.

Many of the wood and concrete structural systems within the building had significant deterioration present, impacting the structural integrity of the building. Miller Consulting Engineers, Inc. (MCE) provided the structural design, analysis and full construction documents to strengthen the seismic and gravity force resisting systems. Due to the layout of the storage walls, we were able to work with both the Owner and Architect to utilize an economic solution that involved adding concrete and masonry shear walls as well as light framed wood shear walls for several areas in the building.   This use of light framed shear walls as well as masonry and concrete shear walls allowed our design team to fully utilize the existing structural systems, and add strengthening measures precisely where they are needed for a safe design.  The result for our client includes an efficient and cost effective structural solution.

Within the structural design, existing timber piling and new grouted micropiles were used to strengthen the foundation elements supporting new shear walls.  This feature represents a low cost method of strengthening the foundation elements for the soil conditions beneath this structure.

Micropile InstallationAs part of the structural design, additional amenities were added to the building including doubling the size of an existing concrete loading dock. The new loading dock area was designed utilizing structural steel beams and a composite concrete deck. Miller Consulting also designed and detailed repairs to several concrete beams, columns, and corbels within the structure using fiber reinforced polymer (FRP) and repair mortars.

Our versatility and experience in the use of a wide variety of materials and construction techniques such as FRP reinforcing, use of micropiles as well as more conventional materials such as concrete, masonry, steel, and light framed construction techniques allowed this project to be constructed in an efficient manner, and minimize construction costs.

Steel ShoringMCE was also involved in construction administration services for this project, which included designing and detailing temporary shoring and stability bracing. The temporary shoring allowed large areas of the floor diaphragms to be removed at one time, as well as permitted construction of the new concrete and masonry shear walls to proceed. Our involvement in this part of the project allowed the contractor to proceed with construction in a manner that has reduced the costs, and maintained an efficient construction schedule. 

The design and construction of this project has been provided in cooperation with the Architect, James Goodman Architecture, and the project owner Facility Development Corporation for Rose City Storage. (Topmost photo was provided by Dan Carter, DJC).


GSA Schedule GS10F105AA
SBA Certified Small Business Enterprise (#P0669937)

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9570 SW Barbur Blvd. Suite 100 Portland, Oregon 97219


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GSA Schedule GS10F105AA

SBA Certified Small Business Enterprise (#P0669937)


At Miller Consulting Engineers, Inc. we specialize in problem solving. If you have a project that needs structural engineering services, feel free to send us a message or call our office. This message will be sent to our response team and one of our engineers will respond to your inquiry.