The ability to precisely identify all necessary work activities for a given item of work is the clearest demonstration of true contract understanding. Within any defined scope, the accuracy of both the cost estimate and the project schedule depends fundamentally on correctly identifying every activity that influences cost and duration. This step must occur before determining the duration of each activity based on work quantities and the crew’s daily production rates.

While listing related activities may appear straightforward, it is far from trivial. Without a solid grasp of the construction materials, methods, and field processes involved, even experienced estimators and planners will struggle to develop a complete and accurate list of activities.

In essence, a deep working knowledge of construction materials and methods is what allows professionals to confidently identify, classify, and sequence activities—whether determining the type of retaining wall involved or organizing the specific construction steps outlined below.

Exercise: Can you correctly determine the wall type?
Use your knowledge of construction materials and methods to analyze the activities shown in the table.

• Step 1: Identify the type of retaining wall these activities relate to.

PREPARE, SUBMIT, AND OBTAIN APPROVALS FOR SPECIFIED SUBMITTALS	FABRICATE AND PLACE REINFORCEMENT FOR THE FOUNDATION	COMPACT BACKFILL MATERIAL IN LIFTS
SURVEY AND SET LINES AND GRADES	MIX, DELIVER, AND POUR CONCRETE FOR THE FOUNDATION	SAMPLE AND TEST SOIL AND CONCRETE PER SPECIFICATION
MOBILIZE AND SET UP AT LOCATION	FABRICATE AND DELIVER CONCRETE MSE PANELS	CONSTRUCT AND INSTALL DRAINAGE SYSTEM
DEWATER EXCAVATION (As Required)	INSTALL PRECAST CONCRETE PANELS IN CONJUNCTION WITH ENGINEERED BACKFILL	BACKFILL IN FRONT OF WALL AT LEVELING PAD TO ACHIEVE FINAL PROFILE GRADE
EXCAVATE AND PREPARE SUBGRADE FOR MSE WALL AND BACKFILL ZONE CONSTRUCTION	INSTALL GEOTEXTILE FABRIC (As Required)	HAUL OFF EXCESS EXCAVATED MATERIALS FROM SITE
EXCAVATE TRENCH FOR THE LEVELING PAD FOUNDATION	PREPARE AND DELIVER BACKFILL MATERIAL PER GRADATION SPECIFIED	DEMOBILIZE AND MOVE OUT OF SITE
FINE GRADE FOUNDATION	PLACE, LAY AND SPREAD BACKFILL MATERIALS IN UNIFORM LIFTS
FABRICATE, PLACE, AND STRIP FORMWORK FOR THE LEVELING PAD FOUNDATION	COORDINATE REINFORCEMENT STRIP PANEL CONNECTION AND LAYING OF STRIPS BETWEEN BACKFILL LIFTS

Exercise: Can you correctly arrange the activities?
Use your knowledge of construction materials and methods to sequence the activities shown in this drag-and-drop exercise.

• Step 2: Sequence the listed construction activities in the logical order they would occur in the field, reflecting a realistic construction workflow.

Throughout the webbook units, we offer detailed list of activities usually associated with each item of work discussed in our webbook units. Additionally, we include interactive content to help gamify learning.

Here is the list of retaining wall types covered in-depth in our webbook unit on An Interactive Webbook on Foundation, and Retaining Wall Construction

1.           Concrete Masonry Unit (CMU) Wall

2.           Gabion Wall

3.           Reinforced Concrete Retaining Wall

4.           Modular Block Retaining Wall

5.           Precast Sound Wall (Precast Panels)

6.           Mechanically Stabilized Earth Wall

7.           Sheet Pile Wall System

8.           Soldier Pile Retaining Wall

9.           Soil Nail and Shotcrete Wall

10.         Secant and Tangent Drilled Shaft Wall Systems with Cased or Uncased Shaft