How to calculate the geosynthetic material drawing instrument? -Huaqiang Electronic Network

How to calculate the geosynthetic material drawing instrument?

Geosynthetics puller calculation:

Calculate the interface pull friction strength as follows:

(17.5.1)

Ï„p

- Drawing frictional strength, kPa;

Tp

- Measured peak level total pull, kN;

L, B

- The length and width of the specimen buried inside the soil, m.

17.5.2 Calculate the drawing friction strength under normal pressure at each level and plot the Ï„p~p curve.

17.5.3 Calculate the drawing friction coefficient f of soil-geosynthetic materials by the following formula:

f = Ï„p / p

(17.5.3)

p

- Normal pressure, kPa;

Ï„p

- Corresponding to the tensile friction strength of σ, kPa.

Experiment method:

Cut the specimen according to the provisions. The width of the specimen should be slightly smaller than the width of the test chamber. The length of the specimen should be such that it is not broken and determined by the test.

2. Each group of tests should be no less than 3 samples.

3. The end of the sample taken from the test chamber should be reinforced, and the sample outside the box should not be greatly deformed during the test.

4. According to the density and state of the design requirements, the soil in the lower part of the test box is carefully filled, and the filling height is flush with the seam, and the soil surface is leveled.

5. The sample is laid on the soil surface, and the tensile end is taken out from the slit. Note that the two sides are symmetrical, then a layer of soil is gently laid on the sample to position the sample.

6. Fill the soil in the upper half of the box according to the density and condition required by the design.

7. The end of the sample is placed flat into the tension clamp, centered and evenly clamped.

8. Put the top cover and the dial indicator in turn, apply the normal pressure, and the time required for consolidation can be referred to the test procedure.

9. Adjust the horizontal loading device, press the LCD display Chinese display. Perform the test parameters required for the test in sequence. Start the test. Use the up and down arrow keys to adjust the desired position of the fixture.

The pull start point is when the tension clamp begins to be stressed. Press the start button, read and record the displacement and horizontal tension. The drawing rate can be referred to the working test procedure, and it is preferable to take 0.5 mm/min for sandy soil.

10. When the pull-out force peaks, continue drawing until the pull-out force is stable, and the test can be stopped.

11. Change one piece and apply another normal pressure, repeat the above steps to complete all the tests.