Publish Time: 2018-06-27 Origin: Site
After obtaining sheet pile, the first step is to determine the load GU 27N and GU 28N acting on the cofferdam. Measurement and mixing - A-30 is a two-component material (15 to 1 ratio). The injection can reach a design depth of 8 meters, and the standard vibration driving is rejected at about 27 to 25 meters, and a diesel hammer must be used to reach the final depth. Important - carefully measure the proportion of 15:1 and mix it thoroughly. GU31N cofferdam may bear loads including earth pressure, additional load, hydrostatic pressure, wave pressure and seismic load. The penetration speed check shows the significant gain due to the GU 28N injection: for L3S and AZ18 piles, the installation time reduces the GU30N coefficient of 8 to 10. 5. driving - the pile must reach the final depth of groundwater or any water within 2 hours.
The lateral force on the cofferdam wall can be calculated according to the method described in the first part of this paper. Due to incomplete mixing of GU 30N, the material may not be able to solidify. Do not mix more than you use. 2 quarts of resin will require 4.25 ounces of sclerosing agent. However, the lateral earth pressure on the retaining wall can not be calculated by classical theory (Rankine, Coulomb, etc.). Or another example is a 7.5 Quart resin requiring 0.5 quarts of hardener. Figure 1 compares the GU28N and refusal of the simple vibration of the L3S pile, and then the driving time of the design depth of the impact drive (L3Sv) and the driving time of the jet / vibration double piles with four jets (L3S V1). Due to the construction of GU27N during the construction period.
When placing steel sheet piles, the depth of GU 30N or GU 31N is insufficient to significantly alter the original stress state in GU30N soil. Pore pressure was observed and they were dissipated in 2 to 10 minutes. Therefore, the lateral pressure GU 31N of the first row of columns is higher than that of the active pressure, because no obvious soil yielding is observed. It is found that there is serious soil disturbance at the distance of 1-2 centimeters of vibration / jet, which is less obvious or almost not traceable at a distance of 10-20 cm from the GU31N pile.
As the excavation continues to the second set of GU27N and GU28N levels, the stiffness of the first group prevents horizontal yielding of the soil near the surface.However, the external lateral pressure GU27N tends to revolve around the support level, so that the certain inward displacement of the sheet will occur at the level of the second sets of rods at the position of these branches. The extraction test (20cm stage) showed that the effective friction decreased by 10-40%. The pile pulled again hits the original depth and further overdrives 50 centimeters. As GU28N mining continues, larger GU28N deflections occur on the lower pillars, thereby mobilizing soil strength and producing arch effects, thereby reducing lateral pressure. POT LIFE about 2 hours! 4. Protection - keep the interlocking device dry before driving. If dry, the pile can be stored for several weeks.
After completing the excavation work sheet piles PAZ4450 PAZ4460, the GU30N and GU31N sheets will be deformed to the position shown in the Ab1 line. Therefore, the obtained lateral pressure graph will have the maximum value on the upper part of the GU27N wall, which is marked by theory. These tests revealed the same order of magnitude of toe resistance and skin friction loss. Rub off any rough edges of the interlocking front before driving. 8. untreated side, the isolation chamber for sandstone and soft to medium clay, trapezoidal distribution is similar to the trapezoidal distribution proposed by Terzaghi and Peck14 (1967) for design. This distribution of GU 31N granular soil. Washing with soapy water before driving may help to make the interlocking device easier to slide. If there is groundwater, the pressure will be added to the trapezoid soil pressure.