Operation of pipe water transmission structure in interaction with subsiding soil

Figure 6. Design concept for the diaphragm's work from the dirt pile on the water supply pipe's side.

The load on the console, as distributed by the law of the triangle, has a maximum intensity at the embedment, which may be calculated using the formula for the conditional cut-out strip of unit width:

q׳_max=φρh_н,кN/m (13)
In the embedment portion, the diaphragm experiences the greatest bending moment due to the action of the dirt pile.
_,кN/m (14)



Figure 7. Head-end diaphragm diagram



Figure 8. Diaphragm design schematic for the situation of a mound of dirt on its side faces.
4. Conclusions

1. Field studies conducted by many scientists have shown that the subsidence of loess soil is

characterized by sharply uneven vertical deformations, soil ruptures in the form of stepped
subsidence cracks, the slope and curvature of the surface of the subsidence funnel,
horizontal movements of the soil. These factors significantly complicate the working
conditions of hydraulic structures on subsident soils.
2. Currently, the bulk of hydraulic structures are designed without taking into account the
specifics of the joint work of hydraulic structures with their loess bases.
3. In many regions of the Republic of Uzbekistan, when erecting irrigation structures on loess
soils, structures made of unified reinforced concrete parts are most widely used.
4. In particular, on the irrigation systems of the Amu-Kashkadarya basin management, where
the bulk of the research was carried out, structures made of reinforced concrete round pipes
with heads made according to the type of diving walls or in the form of reinforced concrete
diaphragms found the most widespread use. In the process of their construction, standard
projects developed for structures on non-sedimentary soils were used.
5. Based on statistical processing of the results of the survey of existing irrigation systems, it
can be concluded that for certain types of hydraulic structures erected on loess soils, it is
necessary to take into account the specifics of their interaction with the base at the design
stage. This need is caused by the specifics of moistening the soil of the base, as well as the
peculiarities of transferring pressure to the soil mass by structures of various designs.
6. Based on the above, it should be concluded that the diaphragm heads of tubular irrigation
structures operating on loess filler soils can be in different loading conditions depending on
the nature of the moistening of the base and the features of interaction with the water
supply elements (Fig. 7-8).
7. At the same time, the specific stress state of the heads depends both on their mass and
geometric dimensions, as well as on the physical and mechanical properties and the
condition of the soils of the bases. This indicates the need to determine the most dangerous
state of the diaphragm at the design stage in accordance with the proposed calculation
formulas and schemes.