Richard L. Smailes, Richard L. Smailes, Ph.D.Ph.D.

Building Chan Chan; Building Chan Chan;

The Construction The Construction Managers’ PerspectiveManagers’ Perspective

University of Florida

Bachelor of Building Construction, UF Bachelor of Building Construction, UF 19761976

Master of Building Construction, UF 1977Master of Building Construction, UF 1977 25 years construction industry 25 years construction industry

experienceexperience Ph.D. Building Construction, UF 2000Ph.D. Building Construction, UF 2000

Mike Mosely co-chairMike Mosely co-chair

Practitioner turned academicPractitioner turned academic

Building Chan Chan; Building Chan Chan;

The Construction The Construction Managers’ Managers’ PerspectivePerspective

What is the labor What is the labor investment? investment?

How many people?How many people?

How long?How long?

Premis:Premis: The labor investment in ancient monumental architecture is an important factor in hypotheses concerning a society's size, organization, and complexity.

Premis:Premis: The labor investment in ancient monumental architecture is an important factor in hypotheses concerning a society's size, organization, and complexity.

Due to the lack of practical analytical methods, complex architecture is often described subjectively offering little quantitative value, resulting in inferences that could be misleading or wrong.

Massive amounts of labor, generations to build

Premis:Premis: The labor investment in ancient monumental architecture is an important factor in hypotheses concerning a society's size, organization, and complexity.

Due to the lack of practical analytical methods, complex architecture is often described subjectively offering little quantitative value, resulting in inferences that could be misleading or wrong.

The application of construction industry estimating and scheduling standards provides a consistent, accurate, and objective means to calculate the labor investment in complex structures.

Ciudadela Rivero

Ciudadela Rivero

1. Define the Scope of Work

2. Perform the Quantity Survey

3. Determine Productivity - Unit Rates

4. Calculate the Project Estimate

5. Develop a Work Plan - Schedule the Project

Construction Methodology

Scope of Work

Define exactly what is to be built

Usually provided by plans and specifications.

In the case of Chan Chan, the ruins are the “as-builts”.

Scope of Work - Work Breakdown Structure

Typical Storeroom Complex at Rivero

Storeroom Complex in Model

Individual Storeroom

Scope of Work – Work Breakdown Structure

Quantity Survey

Calculate the amount/quantity of each piece of work

Usually measured from the plans and specifications.

In the case of Chan Chan, perform field measurements.

Detailed Quantity Survey of a Storeroom

Quantity survey of a storeroom

Original ConfigurationMassive interior adobe walls 11,110 1,910,920 9,895North Sector walls & structures 13,346 2,295,512 25,877Central Sector walls & structures 9,686 1,665,992 22,194Conchone walls 230 39,560 456

Burial Mound 14,334 2,465,448 9,180 9,551

Tapia Walls 24,840 20,400

Totals for Original Configuration 48,706 CM 8,377,432 EA 34,020 CM 88,373 SM

Massive Adobe Wall Addition 17,680 CM 3,040,960 EA 21,370 SM

Volume of Adobes

Number of Adobes

Volume of Tapia

Area of Plaster

Quantity Survey

Productivity - Unit Rates

Calculate the rate of production for each type of work.

Determined by construction techniques

Usually considered proprietary information by construction companies.

Published rates, experiments.

Sources of Productivity - Unit Rates Hand excavation: Field experiment* & contemporary rates

Making adobes: Informants, contemporary rates

Transporting adobes: Field & UN experiments*

Erecting adobes: Practitioner, contemporary rates

Tapia walls: Contemporary rates*

Plastering: Contemporary rates

Harvesting cana: UN studies*

Fab & erect roof: Conceptual estimate

* Rates based on data from underdeveloped countries.

Informant making adobes in the Moche Valley

Construction Techniques

Large adobes

Small adobes

Intermediate adobes

Construction Techniques

Small adobes

Speed leads forvertical alignment

Cana poles for horizontal alignment

Using story poles for horizontal alignment and speed leads for vertical alignment.

Construction Techniques

Story pole

Tapia Blocks

Construction Techniques

Rammed earth construction

Construction Techniques

Direct molding construction

Construction Techniques

Source

Hours Worked

Total Hours

Raw DataWilson 3 8 24 4.59 m3 5.23 hrs/m3

Means 5 8 40 5.09 m3 7.85 hrs/m3

Adjusted Rates

Wilson 5 1 8 40 4.59 m3 8.72 hrs/m3

Means 7 1 8 56 5.09 m3 11.00 hrs/m3

1 Raw data based upon a wheelbarrow, hose, machine mixer for mortar

Add 2 extra persons for manual mortar mixing and transport of mud and water.

Crew Size 4 to 6 Masons

Productivity Range % Optimistic 8.7 -12% Most Likely (Average) 9.9 0% Pessimistic 11.0 12%

(Wilson 2000: pers. comm.; RSMeans 1999: 134)

500

555

500

555

No. of Workers

No. of Adobes Installed

Volume of Adobes Installed

Unit Rate

Recap: Adobe Installation No. of average sized adobes installed per

hour

23hours per cubic meter per worker

2018

hours per cubic meter per worker

hours per cubic meter per worker

Productivity Rates

Recap of Productivity RatesCrew

Activity uom Optimistic Most Likely Pessimistic Size

Hand excavation CM 4.90 6.00 7.30 1Excavate walk-in wells CM 4.90 6.00 7.30 1Manufacture adobes CM 5.20 7.00 7.50 5Transport adobes CM 6.70 7.80 9.00 1Erect adobe structures CM 8.70 9.90 11.00 5Erect adobe walls 0-3m CM 8.70 9.90 11.00 5Erect adobe walls 3-6m CM 12.20 13.80 15.40 5Erect adobe walls 6-9m CM 15.70 17.70 19.80 5Erect tapia walls 0-3m CM 8.50 10.70 12.80 5Erect tapia walls 3-6m CM 11.90 14.90 17.90 5Erect tapia walls 6-9m CM 15.40 19.20 23.00 5Plaster walls 0-3m SM 0.57 0.83 0.98 2Plaster walls 3-6m SM 0.86 1.25 1.47 2Plaster walls 6-9m SM 1.15 1.66 1.96 2Harvest algorrobo LM 2.60 3.25 3.90 4Fabricate roof panels EA 23.90 29.80 36.50 2Erect roof panels EA 3.20 4.00 4.80 2

Labor hours per unit of measure

Project Estimate

Correlate quantities to productivity rates to calculate the estimated labor hours.

A x B = C

Adobe Shell

S-A-01 Manufacture Adobes 40.2 m3 7.0 hrs/m3 280 24%

S-A-02 Transport Adobes 40.2 m3 7.8 hrs/m3 315 27%

S-A-03 Erect adobe walls 40.2 m3 9.9 hrs/m3 396 33%

S-A-04 Plaster adobe walls 64.2 m2 0.83 hrs/m2 53 5%

S-A-05 Install clay floor 4.5 m2 0.95 hrs/m2 4 0.4%

Subtotal - Labor Estimate for Adobe Shell 1,049 89%

Roof

S-R-01Procure & Transport Cana Brava

1800 m 0.0262 hrs/m 47 4%

S-R-02Procure & Transport Cana de Guayaquil

60 m 0.1353 hrs/m 8 1%

S-R-03 Fabricate roof panels 4 ea. 16.0 hrs/ea. 64 5%

S-R-04 Erect roof panels 4 ea. 4.00 hrs/ea. 16 1%

Subtotal - Labor Estimate for Roof 135 11%

Total Labor Hours for Storeroom 1,184

TOTAL Labor Hours

Percent of Total

Project

Activity No.

Item DescriptionEstimated Quantity

Unit Rates

Project Estimate

Project Estimate

2.1 million labor hours

1. Establish Logical Sequences of Work

2. Determine Crew Sizes & Durations

3. Calculate Project Schedule

Work Plan - Scheduling

Factors Effecting Logical Sequences of Work

Laws of Nature

Constructability Issues / Curing Time

Logistics / Room to Work

Common Sense

Owner Requirements

Logical Sequencing of Work

Logical Sequencing of Work – Micro

ErectRoof

Panels

InstallClayFloor

ErectAdobeWalls

TransportAdobes

Manu-factureAdobes

FabricateRoof

Panels

StoreroomComplete

BeginStoreroom

Procurecanabrava

Procurecana

guayaquil

PlasterWalls

This wall came first

This wall abuts the first wall

Logical Sequencing of Work – Macro

Logical Sequencing of Work – Macro

Scheduling – Crew Sizes and Durations

Burial mound

South walls

Tapia walls &interior structure

Total number of workers

Sitework

250250

Results:

250 Workers

could have built it in

5 ½ Years

Calculate the Schedule - Macro

Effects on

Archaeological Theories

The compounds of Chan Chan were the palaces of the kings.

Each ruler built one such structure to house himself, be the seat of government, and serve as the center for the management of his wealth.

Split Inheritance aka 1 King 1 Compound

.. the palace passed to the king's corporation of secondary heirs after his death.

His principal heir became the next king of Chimor and built a new palace.

Split Inheritance aka 1 King 1 Compound

If true, the construction time must be rapid and well within the lifetime of the new king.

Split Inheritance aka 1 King 1 Compound

Based upon the data from Rivero, the construction effort and time was estimated for the remaining compounds.

The largest compound, Gran Chimu, is buildable in 9 years.

Split Inheritance aka 1 King 1 Compound

Rather than sequentially, the last four ciudadelas were built concurrently as pairs.

That, “rapid construction of the last four ciudadelas is compatible with the rise and formulation of quadripartition”

Dual Rule

Dual Rule

Velarde

Bandelier

8.3 years

Dual Rule

Tschudi

Rivero

8.5 years

Dual Rule

Tschudi

Rivero

Velarde

Bandelier

8.5 years

Dual RuleVelarde

Bandelier

16.8 years

Tschudi

Rivero

Could easily come from the local population of 30,000 without any major shifts in the local economy.

The decision to use imported workers from outlying areas would have been by choice not necessity. No need to feed or house workers from the provinces.

Production could be year ‘round.

The Workforce 250 - 1100

… theories regarding the Chimu concerning the control of mass labor and social complexity based solely on the construction of the monumental architecture of Chan Chan may need revisiting.

Ciudadela Rivero

Detailed analysis, renderings, and animations are available on my website.