Earth Pressure and Retaining Walls

By Shreya Laddha|Updated : November 29th, 2021

Through Champion Study Plan for GATE Civil Engineering (CE) 2022, we are providing Earth Pressure and Retaining Walls study notes and other important materials on every topic of each subject.

These topic-wise study notes are useful for the preparation of various upcoming exams like GATE CivilIESBARCISROSSC-JEState Engineering Services examinations and other important upcoming competitive exams.

The article contains fundamental notes on the "Earth Pressure and Retaining Walls"  topic of the "Geotechnical Engineering" subject.

 

Earth Pressure Theories

Rankine's Earth Pressure Theory

Rankine's theory assumes that there is no wall friction (δ = 0), the ground and failure surfaces are straight planes and that the resultant force acts parallel to the backfill slope.

In case of retaining structures, the earth retained may be filled up earth or natural soil. These backfill materials may exert certain lateral pressure on the wall. If the wall is rigid and does not move with the pressure exerted on the wall, the soil behind the wall will be in a state of elastic equilibrium. Consider the prismatic element E in the backfill at depth, z, as shown in Fig.

byjusexamprep

byjusexamprep

Earth Pressure at Rest

byjusexamprep

 

Rankine's Earth Pressure Against A Vertical Section With The Surface Horizontal With Cohesionless Backfill


Active earth pressure:

byjusexamprep

Rankine's active earth pressure in the cohesionless soil

byjusexamprep

Passive earth pressure:

byjusexamprep

Rankine's passive earth pressure in cohesionless soil

byjusexamprep

Rankine's active earth pressure with a sloping cohesionless backfill surface

As in the case of horizontal backfill, active case of plastic equilibrium can be developed in the backfill by rotating the wall about A away from the backfill. Let AC be the plane of rupture and the soil in the wedge ABC is in the state of plastic equilibrium.

byjusexamprep

byjusexamprep

Rankine's active earth pressures of cohesive soils with horizontal backfill on smooth vertical walls

byjusexamprep

Coulomb's Wedge Theory

byjusexamprep

Some Graphical solutions for lateral Earth Pressure are 

  • Culman's solution
  • The trial wedge method
  • The logarithmic spiral

If you are preparing for ESE/ GATE or other PSU Exams (Civil Engineering), then avail Online Classroom Program for ESE and GATE CE:

Online Classroom Program for ESE/GATE CE

You can avail of BYJU'S Exam Prep Test Series specially designed for all Civil Engineering Exams:

BYJU'S Exam Prep Test Series ESE/GATE CE

Thanks

All the Best

 

Comments

write a comment

Follow us for latest updates