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"Twining Acquires DRP"

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Twining, Inc. is expanding its capabilities by acquiring DRP Consulting, Inc. a professional petrography and materials investigation company. This transaction will enable Twining, already a leading provider of concrete, cementitious materials and rock products engineering and research services, to offer a broader scope of services to the construction industry. This strategic acquisition fits into Twining's strategy to expand its services into specialized highly‐technical fields

“We are thrilled to join Twining and look forward to a bright future with the established leader for construction testing services in California.” said David Rothstein, PhD, PG, FACI, President and Principal Petrographer of DRP Consulting, Inc. Dr. Rothstein will continue to guide the DRP team, overseeing all technical aspects of operations and developing the company’s strategy to meet the needs of our clients.

DRP Consulting, Inc. now TI DRP, LLC; doing business as DRP, a Twining Company; will partner primarily with Applied Engineering and Research, a member of the Twining Group of Companies. “Bringing DRP Consulting, Inc. into the Twining Group fulfills a long‐held desire. Adding these capabilities to Twining’s broad spectrum of existing procedures and methods will enable us to serve our clients in exciting new ways.” Said Robert Ryan, CEO and President of Twining, Inc.  “Twining welcomes Dr. David Rothstein, a renowned petrographer and concrete scientist."

About Twining, Inc.

Twining, Inc., based in Long Beach, is the leading provider of construction quality control and engineering services in California. Through its statewide network of offices, Twining provides concrete applied engineering and consulting services; geotechnical engineering; construction materials testing and special inspection; condition forensic investigation of existing structures and pavements; stormwater management; specialty testing; and asphalt pavement quality assurance, design, and materials evaluations.. To learn more about Twining, Inc. visit


TI DRP, LLC; doing business as DRP, a Twining Company; provides a range of services from providing quality assurance to diagnosing causes of deterioration. With extensive experience in concrete materials and early age problems, durability mechanisms, and the performance of slabs ranging from pavements to industrial floors, DRP helps engineers formulate solutions that range from minor repairs to removal and replacement. To learn more about DRP, a Twining Company visit