BACKGROUND

While conducting the Facilities Condition Assessment at Dana Hills High School on Friday, September 1, 2017, Kitchell’s onsite architect observed a concern with the precast concrete tee beams. The tee beams over the boys and girls locker room wings, gymnasium, cafeteria atrium and theater, showed crumbling at the steel rebar turndowns.  Kitchell’s architect notified both the Division of State Architect (DSA) and Kitchell’s project manager, Heather Brown.  Heather Brown notified John Forney via email on September 5, 2017, of the structural concerns along with photos.  John Forney forwarded the email to Clark Hampton and Ryan Carter, Director of Construction to inform them of the concerns.

 

Ryan Carter immediately reached out to Josh Randall with KNA Structural Engineers. A meeting was set up for Friday, September 8, 2017, to walk the site.  In the meantime, Ryan Carter had the District DSA Inspector of Record (IOR) walk Dana Hills High School on Wednesday, September 6, 2017, to report if he had any concerns of structural failure.  The IOR walked the site and didn’t have any immediate concerns of structures failing at Dana Hills High School based on his observations of the existing interior beams.

 

On Friday, September 8, 2017 at 9:00 a.m., a meeting was held at Dana Hills High School that included Ryan Carter, Clark Hampton, Adam Watson (IOR) and Josh Randall structural engineer with KNA.  The structural engineer walked the site and determined that the existing condition was an architectural design flaw not a structural concern or failure.  A timeline of documentation is below.

 

SEPTEMBER 11, 2017:

 

We have concluded that the sand aggregate mortar mix was not a quality mix nor was it well bonded to the lightweight concrete tee beam. It did not provide proper protection for the mild steel ties or the steel pre-stressing tendons, which have corroded in the area of the cap resulting in expansive forces that have spalled the concrete. We did not note damage to any of the tee beams in the bearing area at the integral concrete beam that provides support or that the interior spans of the beams. All damage was limited to the cantilever tails at the eave of the building.

 

As a first step, we recommend that the district authorize us to survey the site and identify any conditions that exist where falling debris could contact students or faculty in accordance with our discussions with the Division of the State Architect’s San Diego office. We recommend the district provide barricades limiting path of travel in those areas until repairs are made. As a second step, we recommend that the district authorize us to perform a thorough survey of all tee beam ends on site and that we prepare a plan identifying every beam in need of repair details and specifications for the proper repair of the affected tee beams.

 

SEPTEMBER 28, 2017:

 

We have concluded that the sand aggregate mortar mix was not a quality mix nor was it well bonded to the lightweight concrete tee beam. It did not provide proper protection for the mild steel ties or the steel pre-stressing tendons, which have corroded in the area of the cap resulting in expansive forces that have spalled the concrete. We did not note damage to any of the tee beams in the bearing area at the integral concrete beam that provides support or that the interior spans of the beams. All damage was limited to the cantilever tails at the eave of the building.

 

As a first step, we recommend that the district authorize us to survey the site and identify any conditions that exist where falling debris could contact students or faculty in accordance with our discussions with the Division of the State Architect’s San Diego office. We recommend the district provide barricades limiting path of travel in those areas until repairs are made. As a second step, we recommend that the district authorize us to perform a thorough survey of all tee beam ends on site and that we prepare a plan identifying every beam in need of repair details and specifications for the proper repair of the affected tee beams.

 

The condition of the tee beams has not compromised the original vertical and lateral load carrying capacity of the structure and their current condition does not preclude the building from continuing to house students and staff.

 

OCTOBER 3, 2017:

 

The tee beam ends for the roofs over the Gymnasium, Student Mall, and Theater all occur over adjacent low roofs. Consequently, the current state of deterioration does not pose any threat of falling debris on students and staff from the tee beam ends in those areas. The tee beam ends for the roofs over the Boys’ and Girls’ Shower and Locker areas occur over exits, walkways and path of travel. We have identified areas on the attached markup of the existing structural roof framing plans where beam ends pose a threat of falling debris on students and staff. Areas of concern are circled in red.

 

We recommend that the loose material at the ends of all tee beams identified on the attached plans be knocked off by mechanical means such that only sound material remains. This is the most straightforward and full proof approach to protecting students and staff from the risks of falling debris.

 

MARCH 20, 2018:

Drawings and specifications for the subject project have been examined and stamped by the Division of the State Architect (DSA) for identification on 3/20/2018. This letter constitutes the “written approval of the plans as to the safety of design and construction” required before letting any contract for construction, and applies to the work shown on these drawings and specifications. The date of this letter is the DSA approval date.

 

SEPTEMBER 18, 2018:

 

The Department of General Services' records indicate that the construction of the referenced project has been completed in accordance with design documents approved by the Department, and that all the Verified Reports covering the construction have been received. Therefore, the Department of General Services Certifies as follows:

 

This project is in compliance with California State regulations as to the safety of design and construction of public schools, and for the accommodation of persons with disabilities.