2009 Geotechnical Consultants Workshop MSE Walls … · 2009 Geotechnical Consultants Workshop MSE Walls Updates Jawdat Siddiqi, P.E. Office of Structural Engineering

2009 Geotechnical Consultants Workshop

MSE Walls Updates

Jawdat Siddiqi, P.E.

Office of Structural Engineering

MSE Walls Updates

• April, 2009 Updates:

◦ Bridge Design Manual

Section 204.6.2.1 Stage 1 Detail Design Submission for

Proprietary Walls

Section 303.5.1 Wall Design Requirements for Proprietary

Retaining Walls-Work Performed by the Design Agency

Figures 303.5.1-1, 303.5.1-2, 303.5.1-3 303.5.1-5,

303.5.1-6 & 303.5.1-7

ODOT-Office of Structural Engineering

Previous 2004 BDM Sec 204.6.2.1

RequirementsDetermine the height of the wall (h) for minimum soil

reinforcement lengths as follows:

When the surface of the retained soil is level, measure

(h) from the top of the concrete leveling pad to the top

of the concrete coping.

When the surface of the retained soil is sloping,

measure (h) as shown in AASHTO Figure 5.8.2B.

When the surface of the retained soil is supporting an

abutment, measure (h) from the top of the concrete

leveling pad to the profile grade elevation at the face of

the wall.



AASHTO Figure 5.8.2A

MSE Wall with Level Backfill

MSE Wall with Sloping Backfill


AASHTO Figure 5.8.2B

MSE Wall with Broken Backslope


AASHTO Figure 5.8.2C

Current 2004 BDM Sec 204.6.2.1

RequirementsDetermine the height of the wall (H) for minimum soil

reinforcement lengths as follows:

If the wall is not located at an abutment, measure (H) as

the elevation difference between the top of the wall

where the finished grade intersects the back face of the

wall and the top of the leveling pad (AASHTO Article

5.8.1).

If the wall is located at an abutment, measure (H) as the

elevation difference between the profile grade at the

face of the wall and the top of the leveling pad.


Current 2004 BDM Sec 204.6.2.1

Requirements The soil reinforcement length shall not be less than 70%

of the wall height (H) or 8’-0” [2.5 m], whichever is

greater. Only increase this minimum soil reinforcement

length as necessary to meet external stability

requirements (sliding, bearing resistance, overturning,

overall global stability). Generally, the soil

reinforcement length should not be greater than 150%

of the wall height (H). Provide calculations with the

Foundation Report, BDM Section 202.2.3, that justify

soil reinforcement lengths exceeding 0.70H.



AASHTO Figure 5.8.2A

MSE Wall with Level Backfill

MSE Wall with Sloping Backfill


AASHTO Figure 5.8.2B

MSE Wall with Broken Backslope


AASHTO Figure 5.8.2C

MSE Wall SS840 updated

o Supplement Specifications (SS 840)

Pipe Sleeves Material, if recycled polyethylene,

submit certified test data conforms ASTM F 2648

Include a live load surcharge of 250 psf unless the

backfill above the wall is sloped steeper than 4H:1V


Design Requirements

Specify soil reinforcement length in the

plans only if the soil reinforcement length

greater than 70% of the wall height is

needed for external stability.


BDM Section 303.5.1 Updates

6” corrugated perforated plastic pipe with filter fabric,

no porous backfill within the limit of SGB

Pay limits for wall and roadway quantities

Soil reinforcements attached to abutments

◦ Regardless of abutment type and foundation type, minimum of

one row of soil reinforcements shall be attached to the backside

of the abutment footing.

◦ These additional reinforcements are necessary to resist

horizontal bridge and backwall forces, and to prevent load

transfer to the coping and facing panels.

◦ To estimate select granular backfill quantities, Designer’s may

assume these additional reinforcements to be of the same length

as those attached to the facing panels.


BDM April, 2009 Figures updates



The 1:1 Slope was eliminated

6” corrugated perforated plastic pipe with

filter fabric, no porous backfill within the

limit of SGB

Pay limits for MSE wall and roadway

quantities




Back to Back MSE Walls• Separation between 203 Embankment and SGB

◦


Back to Back MSE Walls• Separation between 203 Embankment and SGB

◦


Preferred Geometry for MSE wall

Supporting Bridge Abutment

• Straight Walls

•Turned back walls up to 45 degree

• Curved walls

•Turned back walls up to 90 degree

• Avoid acute corners


General Requirements

Frictional resistance against sliding should be

obtained using the coefficient (f =tan

Foundation Report for MSE Wall Supporting

Bridge Abutment (BDM 202.2.3)◦ Calculations for bearing pressure and bearing capacity for the in-

situ materials below the MSE wall.

◦ Settlement Calculations.

◦ Consider the effect of settlement.

◦ Include all construction constraints, such as soil improvement

method, that may be required.


MSE Wall Shop Drawings Submittal

Submit four copies of the working drawings, design

calculations and acceptance letter to the Engineer at least 30

days before construction.

Submit drawings and calculations in electronic format.

The Engineer will submit the drawings and calculations to the

Office of Structural Engineering for review. The review is

performed within 21 days of receiving the submission.

MSE wall Questions - OSE

Jawdat Siddiqi, P.E

Assistant Administrator/Foundation Engineer

Bashar Al-Tarawneh, Ph.D., P.E.

Foundation Engineering Coordinator


Thank You


Documents

2009 Geotechnical Consultants Workshop MSE Walls … · 2009 Geotechnical Consultants Workshop MSE Walls Updates Jawdat Siddiqi, P.E. Office of Structural Engineering