“WDP has successfully utilized equipment from Impact-Echo Instruments, LLC to investigate a wide variety of civil infrastructure over the last 10 years ranging from bridges, parking structures and buildings to specialty structures such as tanks, storm-water retention boxes, flood control channels, and marine structures. Flaws such as delaminations, honeycombing, and voids in concrete, voids in grout of bonded post-tensioning tendons, and sub-grade voids under slabs have been successfully detected and confirmed using this technology. Impact-Echo has been used by WDP on over a hundred structures in the evaluation of thousands of individual concrete members. Over 100,000 signals have been recorded and analyzed over the last 10 years. Impact-Echo has become the leading investigative tool used by WDP personnel in the forensic evaluation of structural concrete. The successful application of this technology and its ability to accurately detect concrete flaws has resulted in the savings of tens of millions of dollars in repair and replacement costs for our clients.”
– Randall W. Poston, Ph.D., P.E. / Principal / WDP & Associates, Inc. / Austin, Texas
“Levelton Engineering has been involved in the development and use of Impact-Echo testing for structural diagnostic purposes for over 12 years. We have found Impact-Echo to be a highly powerful and reliable technique for nondestructively locating and characterizing defects in concrete structures. Some examples of Levelton’s successful use of the Impact-Echo technology include: locating internal tearing and delaminations in slipformed silo walls; locating delaminations in bridge decks and parking slabs; locating voids below grouted machine base plates; locating honeycomb and similar voids within slipformed airfield pavements and reinforced concrete members; and measuring thickness of pavements and slabs on grade. Impact-Echo has become an essential part of our tool chest for evaluating the condition of many types of concrete structures.”
– Neil Cumming, President / Levelton Engineering Ltd. / Richmond, BC, Canada
“We are using an instrument from Impact-Echo Instruments to locate voids beneath 80-90mm of a steel fibre concrete floor, forming the cap over cushion piles. We have located faulty pile heads, mapped the extent of voids and associated honeycombing, and after grouting checked for residual voids and concrete strength gain. No other available test method is appropriate. We also regularly use impact-echo for forensic studies of historic buildings, including recently St. Paul’s Cathedral, London, The Federal Reserve Building in New York, and the U.S. Capitol Building, Washington.”
– George Ballard / GBG Inc., New York, USA / GB Geotechnics Ltd., Cambridge, England
“The Federal Highway Research Institute of Germany (BASt) has used the equipment of Impact-Echo Instruments for almost two years. The impact-echo system was used successfully for thickness measurements, detection of delaminations and detection of voids and honeycombing. The system was also used in investigations of prestressed concrete bridges to detect voids in the grouting of tendon ducts. A procedure for verification of the thickness of inner lining of new road tunnels was developed by BASt, and adopted by the Federal Ministry of Transport, Building and Housing in Germany.”
– Dr.-Ing. Juergen Krieger, Bundesandtalt fuer Strassenwesen (Federal Highway Research Institute), Germany
“We have used the impact-echo method successfully in 13 projects since June 1999. These include:
1. detecting voids in tendon ducts in pre-stressed beams and slabs;
2. determination of retaining wall thickness;
3. detection of honeycombing in basement wall and marine spun piles (verified by cores);
4. determination of bonding between metal inserts and concrete in railway ties (verified by cores); and
5. determination of bonding condition between topping concrete and pre-cast hollow-core slab.”
– Zheng Yong-Hao / SETSCO Services Pte Ltd. / Singapore
“As an impact-echo researcher, I am very impressed by the products of Impact-Echo Instruments, with which I have done many impact-echo tests successfully, such as crack detection and thickness measurements. A test system integrating two handheld transducers, a 14-bit A/D converter and a user-friendly software makes the impact-echo field test system accurate and easy to use.”
– Professor Yiching Lin, Ph.D. / National Chung Hsing University / Taiwan
“Based on our experiences with the technology, we strongly recommend the use of Impact-Echo as an effective tool to determine the likelihood of flaws within plate-type structures, including garage slabs, plaza deck slabs and foundation walls. It is particularly valuable when there is a concealed surface on the structure (e.g. the topside of a plaza deck slab).”
– Alan Cohen / Halsall Engineers – Consultants / Toronto, Canada