Experts in the Principles and Practice of Post-Tensioned Concrete and Seismic Design
The principals of Seneca Structural Engineering are actively involved in building code development through the American Concrete Institute and the Post-Tensioning Institute, as well as book writing and teaching in the University Systems of California and online professional webinars. This allows our designs to remain state of the art.
Specialists in post-tensioning and seismic design, not generalists in everything.
Seneca Structural Engineering, Inc. provides specialized post-tensioning and seismic design. That focus — rather than a broad, do-everything practice — is what lets the firm push into more efficient, more inventive solutions for both new construction and existing structures that need strengthening.
The majority of the software used by the firm was written by the principals and focuses on exactly the types of projects that the firm regularly engineers, creating even more efficient designs.
The firm is led by two principals who between them have designed, evaluated, and published on post-tensioned concrete and seismic design since the firm's inception in 1998: K. Dirk Bondy, S.E., and Bryan Allred, S.E. Their book and design software have been used by students and practicing engineers for learning and designs well beyond Seneca's own project list.
- 01 Post-tensioning is engineered on every project to meet not only the latest code requirements, but the current standards of care and practice
- 02 Principals perform calculations and create drawings directly; no hand-off to junior or drafting staff
- 03 Calculation packages are organized to help plan checkers and peer reviewers easily understand and follow the design intent, as opposed to overwhelming them with volumes of muddled computer output
- 04 Knowledge gained is passed on to other practicing engineers and the next generation through our book, publications, online webinars and University courses for the benefit of the entire industry
Seven services. One discipline underneath all of them.
For examples of the structure types we work on, see Our Work.
Design of Post-Tensioned Structures
New-construction design of post-tensioned concrete — slabs, beams, and foundations — engineered by the principals on every project.
Evaluation of Post-Tensioned Structures
Condition assessment and analysis of existing post-tensioned structures, including tendon corrosion and restraint-cracking evaluation.
Seismic Evaluations
Seismic assessment of existing concrete and steel buildings against current code, identifying deficiencies and strengthening options.
Vertical and Seismic Retrofit of Existing Structures
Strengthening design for existing structures, including internal and external post-tensioning retrofit systems.
Peer Reviews
Independent structural peer review of post-tensioned and seismic designs for other engineers, architects, and building departments.
Plan Check Services
Plan check review services for jurisdictions and third-party plan check firms on post-tensioned and seismic-related submittals.
Consulting to Other Structural Engineers
Technical consulting support to other structural engineering firms on post-tensioned design, detailing, and construction issues.
From our projects, not a stock library.
Construction-phase photography and project credits from Seneca's work, organized by structure type.
A sample of parking structures we've engineered.
Placeholder cards below — send over your own photo and project notes for each and I'll drop them in.
Hotel projects.
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Auto dealership projects.
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Podium projects.
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External PT strengthening projects.
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Storage facility projects.
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Assisted living facility projects.
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Post-tensioning, seismic analysis and flying explained, on camera.
Have another video to add? Send the link and I'll drop in another card.
Design of Post-Tensioned Concrete
A YouTube playlist covering the design of post-tensioned concrete structures.
→ Watch on YouTube ↗Seismic Analysis Lectures — ASCE 7-22 (2026)
A YouTube playlist by K. Dirk Bondy, S.E., covering seismic analysis under ASCE 7-22.
→ Watch on YouTube ↗Published, presented, and debated since 1996.
Original articles by Seneca's principals, still cited in post-tensioning and seismic design practice.
Post-Tensioned Concrete: Principles and Practice
By K. Dirk Bondy and Bryan Allred - the textbook used for teaching at UCLA and Cal Poly, SLO for over a decade, as well as by practicing structural engineers. Available in hardcover or as an immediate-download Ebook.
Two licensed structural engineers. Every project.
K. Dirk Bondy, S.E.
Dirk Bondy received his Architectural Engineering BS degree from Cal-Poly, San Luis Obispo in 1988 and his MS degree in Structural Engineering from UC Berkeley in 1989. He is president of Seneca Structural Engineering, Inc. in Irvine, CA and is a registered structural engineer in the states of California, Nevada, Arizona, Utah and Colorado.
In addition to being the engineer of record on hundreds of structures, Mr. Bondy has taught “Design of Prestressed Concrete” at UCLA and at Cal Poly, San Luis Obispo and is the co-author of “Post-Tensioned Concrete Principles and Practice.”
He is a licensed private pilot (multi-engine and instrument rated) with over 1450 hours of flying time.
Bryan Allred, S.E.
Vice President of Seneca Structural Engineering, Inc., focusing on the design and detailing of reinforced concrete structure utilizing post-tensioned floor systems with experience ranging from parking structures, podiums, hotels, offices and storage facilities.
Bring in the specialists early.
Email either principal directly — no forms, no queue. If you're not sure which structure type applies, just describe the project.
Seneca Structural Engineering, Inc.
18301 Von Karman Ave., Suite 440
Irvine, CA 92612