How it Works

How

How MAQT Works?

Ultrasonic Device

Schmidt Hammer Devic

MAQT Analysis

Result

Procedure

MAQT Procedure for Testing Concrete Members

Accurate Method to Evaluate the Compressive Strength of Concrete by Ultrasonic & Schmidt Hammer Device.
(MAQT) is limited to evaluate compressive strength for concrete by using ULTRASONIC & SCHMIDT HAMMER with reliability estimated by more than 90%.

01

Test area preparation (limited for concrete section)

  1. The test area must be dry, and should not be frost. (always better to check the temperature and the recommended temperature is between (10-60 C).
  2. On the base of performing all hammer tests, in the same manner, choose (2) proper sides from the signed concrete member and avoiding places close to the edges sketch a line (on both chosen sides) with 50 cm length, if there is no space for this length sketch (2) parallel lines far from each other by 4 to 6 cm (the sketched line should not be interrupted by segregation area and reinforcement steel specifically the main bars).
  3. Remove any obstructed material (plastering) and refine the surface with hand or specific device for refining on each line 5 to 6 cm width. (Clear cover should be thin as much as possible).
  4. Divide each lines into 23 sections (each section should not be less than 2.0 cm and each section should be located at a clear surface.

02

Specific information related to ULTRASONIC & SCHMIDT HAMMER

  1. Prior to carrying out this measurement, make sure the devices are working accurately and it is not out of calibration (Adjust the ultrasonic device measurement with the reference bar).
  2. For ultrasonic device-specific transducers for concrete with (25-100 kHz) should be attached and measurement must be verified (the transmitting & receiving transducers should be touched with each other by specific gel meanwhile the measurement should be zero). Transducers with 100 kHz are recommended for thin thickness.

03

User information for ULTRASONIC & SCHMIDT HAMMER device

  1. Avoiding places close to the edges and steel parallel to the direction of pulse propagation, choose (3) points on one of the selected sides and measure the distance between each of them and their alternative points on the other selected side(depending on ultrasonic test method, Direct Or Simi direct) in (mm) then clean all points and fill the existing voids around each point on both sides by specific gel and record the ultrasonic pulse time between each point and its alternative point on the other side in (μs).
  2. Record (46) hammer rebounds (23 from each side) after cleaning transducer places if they laid on the sketched lines.
  3. If there is no segregation and the coarse aggregate particles well distributed in the concrete, all 46 hammer rebound readings can be taken on one side on (2 or 3) parallel sketched straight lines (5 to 10)cm far from each other, near to the transducers places or pulse paths as much as possible.
  4. All hammer tests readings on all lines are complementary to the other, and there are only two rows for hammer test readings so all hammer test readings should be listed in two sketched rows while data entering.
  5. In case there is erratic reading, it is recommended to omit the erratic reading and test different locations.
  6. Observation, following the user instructions for ULTRASONIC & SCHMIDT HAMMER, has a significant influence to record accurate results.

Note

The information must be provided

  • Project Name
  • Location
  • Technician Name
  • Estimated Temperature

Note
  1. Ultrasonic Indirect method is not suitable in MAQT because it might give wrong results.
  2. If the result gives (Check the entered data) it means:
    • There is mistake in entered data.
    • The result is too low. (FĆ<5mpa)