Monograph No. 104
Theoretical Reconstruction of Tōdaiji's East Pagoda
Main Report
Contents
Chapter I: Introduction
1. Background and Objectives 1
2. Research Framework and Processes 7
3. Report Compilation 18
Chapter II: History of the East and West Pagodas and Past Theoretical Reconstructions
1. History of the East and West Pagodas 23
2. Past Theoretical Reconstructions 32
Chapter III: Excavation Findings
1. Excavation Overview 41
2. Ground Floor Plan, Rammed-Earth Platform （Kidan）,and Surrounding Elements 44
3. Sorting Excavated Artifacts 51
4. Changes between the Nara-Period Pagoda and the Kamakura-Period Pagoda 60
Chapter IV: Examining Pillar Base Stones and Determining Pillar Diameters
1. Introduction 61
2. Findings 65
A. Excavated Fragments of Pillar Base Stones 65
B. Pillar Base Stones Alleged to Be from Tōdaiji 69
3. Comparing Base Stones and Organizing Data for Reconstruction 92
A. Analysis of Central Pillar's Base Stone 92
B. Analysis of Other Base Stones 95
C. Organizing Data for Reconstruction 96
4. Determining Pillar Diameter for the Nara-Period East Pagoda's Ground Floor 97
A. Introduction 97
B. Ratios between Pillar Diameters and Pillar Seat （Hashiraza 柱座）Diameters of Base Stones 97
C. Differences in Actual Dimensions for Pillar Diameters and Pillar Seat（ Hashiraza） Diameters of Base Stones 97
D. Correlations between Pillar Diameters and Pillar Seat （Hashiraza）Diameters of Base Stones 99
E. Estimating the Pillar Diameter for the Nara-Period East Pagoda's Ground Floor 99
F. Summary 100
5. Summary 101
Chapter V: The Height of the Nara-Period East Pagoda of Tōdaiji
1. Introduction 103
2. Past Research on the Height of the Nara-Period East Pagoda 104
3. Daibutsuden Inscriptions 106
4. Key Historical Records 107
5. Interpretations of the Pagoda's "Height" 108
6. Reviewing Handwritten Manuscripts for Key Historical Records 111
7. Basis for Ban Nobutomo's Revisions 115
8. Summary 118
Chapter VI: Superstructure of the Nara-Period East Pagoda of Tōdaiji
1. Baseline Parameters and Research Materials 119
A. Baseline Parameters 119
B. Research Materials 119
C. Research Process 130
2. Vertical Proportions 132
A. Introduction 132
B. Research Materials 132
C. Plausibility of the Nara-Period East Pagoda 140
D. Summary 141
3. Ground Floor 143
A. Dimensions Based on Eave Overhang 143
B. Foundation and Pillar Layout 146
C. Framework （Jikubu） 151
D. Bracket Complexes （Kumimono） 160
E. Intermediate Supports （Nakazonae） 188
F. Eaves and Roofing 191
4. Frame Assembly of Upper Stories 207
A. Assembly of Each Story 207
B. Assembly of the Central Pillar 214
5. Scale of the Seventh Story Based on Finial 221
A. Introduction 221
B. Finial Design and Scale 221
C. Total Bay Width of the Uppermost Story Based on Finial Scale 224
D. Bay Widths of the Uppermost Story Based on
Finial Scale and Construction Method 229
E. Summary 235
6. Upper Stories 238
A. Floor Plans 238
B. Height of Each Story 246
C. Framework （Jikubu） 251
D. Bracket Complexes （Kumimono） 254
E. Intermediate Supports （Nakazonae） 259
F. Eaves and Roofing 260
7. Fixtures 265
A. Bay Fittings 265
B. Railings 268
C. Central Altar 274
D. Ground Floor Interior Ceiling and Surrounding Elements 279
E. Ground Floor Interior Flooring 285
8. Decorative Metal Fittings and Color Schemes 290
A. Decorative Metal Fittings 290
B. Color Schemes 295
C. Plaques 298
9. Preparing the Original Reconstruction 304
A. Structural Types 304
B. Main Dimensions 306
Chapter VII: Evaluation of Structural Analysis of the Nara-Period East Pagoda of Tōdaiji
1. Introduction 309
2. Reference Materials Concerning Dead Loads 313
A. Background 313
B. Material Quantities and Specifications 313
C. Building Loads Based on Material Quantities 315
3. Verification Ratios 316
A. Nara-Period East Pagoda 316
B. Kōfukuji's Five-Story Pagoda 317
C. Comparative Analysis 318
4. Summary 326
Chapter VIII: Superstructure of the Kamakura-Period East Pagoda of Tōdaiji
1. Baseline Parameters and Research Materials 327
A. Baseline Parameters 327
B. Research Materials 329
C. Research Process 332
2. Dimensions and Forms Common to the Chōgen and Eisai/Yōsai Reconstructions 333
A. Foundation 333
B. Floor Plans 333
C. Heights 334
D. Frame Assembly of Upper Stories 335
E. Ground Floor Pillar Diameter 336
F. Roofing 337
G. Fixtures 337
H. Decorative Metal Fittings and Color Schemes 338
3. The Chōgen Reconstruction 341
A. Diminishing Widths of Each Story 341
B. Diminishing Heights of Each Story 341
C. Frame Assembly of Upper Stories 344
D. Framework （Jikubu） 345
E. Bracket Complexes （Kumimono） 347
F. Intermediate Supports（ Nakazonae） 349
G. Eaves 350
H. Fixtures 350
I. Decorative Metal Fittings and Color Schemes 353
4. The Eisai/Yōsai Reconstruction 355
A. Characteristics of Tōdaiji's Belfry 355
B. Basic Unit for Building Design 358
C. Diminishing Dimensions of Ascending Stories 360
D. Ground Floor 360
E. Frame Assembly of Upper Stories 368
F. Upper Stories 368
G. Fixtures 369
5. Findings and Remaining Issues 378
A. Items Common to the Chōgen and Eisai/Yōsai Reconstructions 378
B. The Chōgen Reconstruction 378
C. The Eisai/Yōsai Reconstruction 380
6. Preparing the Original Reconstructions 382
A. Structural Types 382
B. Main Dimensions 384
Chapter IX: Conclusion
1. Research Findings 388
A. Chapter II: History of the East and West Pagodas and Past Theoretical Reconstructions 388
B. Chapter III: Excavation Findings 389
C. Chapter IV: Examining Pillar Base Stones and Determining Pillar Diameters 389
D. Chapter V: The Height of the Nara-Period East Pagoda of Tōdaiji 390
E. Chapter VI: Superstructure of the Nara-Period East Pagoda of Tōdaiji 391
F. Chapter VII: Evaluation of Structural Analysis of the Nara-Period East Pagoda of Tōdaiji 398
G. Chapter VIII: Superstructure of the Kamakura-Period East Pagoda of Tōdaiji 400
H. Appendixes: Other Research 405
2. Significance of Research Findings 409
A. The Nara-Period East Pagoda 409
B. The Kamakura-Period East Pagoda 417
3. Remaining Issues and Future Developments 420
Appendix I: The Nara-Period Daibutsuden's Pent Roof Enclosure (Mokoshi) and Surrounding Elements
1. Introduction 423
2. Baseline Parameters and Research Materials 424
A. Excavation 424
B. Research Materials 426
C. Past Research 426
D. Summary 428
3. Reconstruction 430
A. Height of Building Core （Shuoku） 430
B. Framework （Jikubu） 431
C. Bracket Complexes （Kumimono） 432
D. Eaves 436
E. Fixtures 436
F. Decorative Metal Fittings and Color Schemes 436
4. Summary 438
Appendix II: Miscellaneous Research
1. Additional Investigations of Base Stones 439
A. Introduction 439
B. Findings 442
C. Comparative Analysis of Stone Materials 472
D. Summary 473
2. Architectural Materials Owned by Tōdaiji 475
A. Introduction 475
B. Measurement Survey 477
C. Dendrochronological Dating 486
D. Organizing Data for Reconstruction 487
E. Renovation Period of Tōdaiji's Tegaimon 487
F. Summary 489
3. Materials Used to Create Reference Drawings 491
A. Introduction 491
B. "1:20 Elevation and Section Drawing of Gangōji's Pagoda in Nara" 492
C. "1:20 Elevation and Section Drawing of Kōfukuji's Five-Story Pagoda" 494
D. Summary 495
Appendix III: Structural Evaluations
1. Variant Reconstruction of the Nara-Period East Pagoda with Inner Pillars 497
A. Introduction 497
B. Verification Ratios 497
C. Comparative Analysis with Original Reconstruction of the Nara-Period East
Pagoda 500
D. Summary 502
2. Stress Distributions 503
A. Introduction 503
B. Original Reconstruction of the Nara-Period East Pagoda 504
C. Kōfukuji's Five-Story Pagoda 507
D. Variant Reconstruction of the Nara-Period East Pagoda with Inner Pillars 508
E. Comparative Analysis 509
F. Summary 510
Appendix IV: Reference Drawings
1. Reference Drawings of the Nara-Period Daibutsuden's Pent Roof Enclosure (Mokoshi) and Surrounding Elements 511
A. Introduction 511
B. Reference Drawing a 511
C. Reference Drawing b 512
D. Reference Drawing c 512
E. Summary and Remaining Issues 512
2. Reference Drawings of the Nara-Period East Pagoda 516
A. Introduction 516
B. 32 - Jō Reference Drawing a 517
C. 32 - Jō Reference Drawing b 525
D. Summary and Remaining Issues 527
List of Sources for Figures 531
Abstract Translations 547
English Abstract 549
Chinese Abstract 573
Korean Abstract 591
Abstract of the Report 610
Figures and Structural Analysis Materials
Contents
Figures
Reconstruction Drawings
Nara-Period East Pagoda Figs. 1 - 15
Kamakura-Period East Pagoda Figs. 16- 19
Reference Materials
Past Reconstruction Drawings Figs. 20- 30
Excavation Drawing Fig. 31
Paintings Figs. 32- 43
Similar Buildings Figs. 44- 77
Historical Records Figs.一（1）- 一五（15）
※ From the end of "Reference Materials"
List of Sources for Figures
Structural Analysis Materials
Preface （ 1）
Original Reconstruction of the Nara-Period East Pagoda （ 5）
Kōfukuji's Five-Story Pagoda （ 119）
Variant Reconstruction of the Nara-Period East Pagoda with Inner Pillars （ 191）
Abstract of the Report
Abstract
Chapter I: Introduction
This report concerns a study on the theoretical reconstruction of the east pagoda of the temple complex of Tōdaij（東大寺） in Nara, Nara Prefecture. It was conducted by the Nara National Research Institute for Cultural Properties（Nabunken） on behalf of Tōdaiji.
Emperor Shōmu（701-756） commissioned Tōdaiji's construction as a state-sponsored temple in the eighth century. The temple is famous for housing the "Great Buddha of Nara." During the Nara period （710-794）, two seven-story pagodas--a west and east pagoda--were constructed at Tōdaiji to the south of the hall housing the Great Buddha, called the Daibutsuden（see Fig. I -1-1）. In 1180, the east pagoda was destroyed in a fire when Taira forces attacked Tōdaiji to retaliate for the temple's monks having sided with the Minamoto clan in an earlier battle during the Genpei War（1180-1185）. The east pagoda was rebuilt in 1223, during the Kamakura period（1185-1333）, but burned down again after being struck by lightning in 1362. It was not rebuilt following that incident. The west pagoda burned down when it was struck by lightning in 934 and was never rebuilt.
In 2013, Tōdaiji drafted and adopted the Tōdaiji keidai seibi kihon kōsō（"Basic Framework for Site Management at Tōdaiji"）. The document outlined plans to excavate the site of the east pagoda and create a reconstruction based on excavation findings. In 2015 and 2016, an excavation team made up of researchers from Tōdaiji, Nabunken, and the Archaeological Institute of Kashihara excavated the east pagoda site. The excavation produced valuable information for creating a theoretical reconstruction. The team found well-preserved archaeological features of the east pagoda from two time periods: its original construction during the Nara period and its later reconstruction during the Kamakura period. The excavation findings were published in Tōdaiji tōtōinseki keidai shiseki seibi jigyō ni kakawaru hakkutsu chōsa gaihō 1（"Tōdaiji's East Pagoda Site, Excavation Report for Projects Concerning Historic Site Management on Temple Grounds, Part One" Tōdaiji, 2018）.
Upon receipt of excavation findings, Tōdaiji moved forward with a study to create a theoretical reconstruction of the Nara-period east pagoda and hired Nabunken for that purpose in 2018. The same year, Tōdaiji hired the Japanese Association for Conservation of Architectural Monuments（Bunkenkyo） to create architectural drawings and conduct structural analysis for the theoretical reconstruction in consultation with Nabunken. Bunkenkyo outsourced structural analysis to the company Tateishi Kōzō Sekkei （"Tateishi Structural Design"）. Also in 2018, Tōdaiji assembled a panel of experts on architectural history, building construction, and Japanese history to establish an advisory committee for the research project. Tōdaiji convened the committee twice a year until 2021. Nabunken consulted the committee on research findings while conducting the study. In 2021, a theoretical reconstruction was approved and the study ended. This report was compiled following that decision and published in March 2024.
The objective of the study was to create a theoretical reconstruction of the Nara-period east pagoda at Tōdaiji. The study was further expected to uncover new discoveries through excavations and a review of existing literature. The theoretical reconstruction was created using an interdisciplinary approach combing the fields of architectural history, archaeology, history, and cultural property conservation science. As preliminary research to aid in the study's objective, theoretical reconstructions were also made for the Daibutsuden constructed during the Nara period and the east pagoda that was rebuilt in the Kamakura period. The study's scope was limited to producing a theoretical reconstruction detailed enough to build a model of the Nara-period east pagoda. Research into other theoretical reconstructions was limited to understanding each structures' overall appearance and was not concerned with reproducing the buildings in detail.
The chapters in this report are organized as follows. Chapter II is a review of existing literature（past theoretical reconstructions）. Chapter III presents excavation data. Subsequent chapters discuss the findings of this study. Chapter IV describes excavated fragments of pillar base stones（soseki 礎石） and estimates the diameters of the pillars that stood atop them. Chapter V determines the height of the pagoda by examining historical records and working back through handwritten manuscripts. Chapters IV and V establish baseline parameters concerning the pagoda's reconstruction. Chapter VI outlines our team's research into the Nara-period east pagoda and presents a theoretical reconstruction based on the findings described in Chapters III through V. Chapter VII presents analysis used to determine if the theoretical reconstruction of the Nara-period east pagoda proposed in Chapter VI would be structurally viable as a building and would not collapse under its own weight during construction or upon completion. Temporary wind, earthquake, and snow loads, as well as structural changes over time, were not considered. Chapter VIII describes our research on the east pagoda that was rebuilt in the Kamakura period and presents our theoretical reconstructions of this later pagoda, which were made to aid in reconstructing the Nara-period pagoda. Chapter IX contains a summary of the study's findings and conclusions. The appendixes present research conducted in the process of this study that did not end up directly contributing to creating a theoretical reconstruction.
Appendix I examines Tōdaiji's original Daibutsuden constructed during the Nara period. Appendix II contains research reports on several topics, including: stones found across Japan that could potentially have been pillar base stones taken from Tōdaiji, historic architectural materials owned by Tōdaiji, and architectural drawings of the five-story pagoda of Gangōji （元興寺; see Fig. 43 and Fig. Appx. II -3-1） that burned down in 1859, which was thought to be similar to Tōdaiji's east pagoda.
Chapter II: History of the East and West Pagodas and Past Theoretical Reconstructions
Multiple historical documents list the heights of Tōdaiji's seven-story pagodas in the Nara period. Those described in published materials（i.e., historical documents that were printed or reprinted） can broadly be divided into those specifying just over 23 jō（approx. 70 m） and those specifying just over 33 jō（approx. 100 m）. Jō（丈） is a unit of measurement corresponding to 10 shaku（尺）. Interpretations of what this height refers to differed in previous studies, with some researchers considering it to be the total height including the finial and others considering it to be the height of the pagoda body（tōshin 塔身） alone（see Fig. I -3-2）.
Amanuma Shun'ichi（1876-1947） made a theoretical reconstruction（hereafter "the Amanuma reconstruction" ; see Fig. 20, 21 and Fig. II -2-1） in 1910 that places the total height at just over 30 jō（100 m）. He interpreted the height of "just over 23 jō" described in historical records as referring only to the pagoda body height, and that the total height including the finial would have been just over 30 jō. He hypothesized the ground floor was three bays square after examining the site（bay refers to the space between two pillars）.
Adachi Kō（1898-1941） reviewed the heights listed in historical records for the pagodas and concluded they all referenced the total heights including the finial. For the east pagoda, the two heights of just over 23 jō and 33 jō are found in historical records. Adachi determined the height to be "just over 33 jō" based on the pagoda's proportions（hereafter "the Adachi reconstruction"）. He did not make any reconstruction drawings, but by coincidence, the height in the Adachi reconstruction was close to that of the Amanuma reconstruction. This led to a general perception that that seven-story pagodas at Tōdaiji had a total original height of approximately 100 meters.
Hakozaki Kazuhisa（1970-） made a theoretical reconstruction in 2003 indicating the total height was approximately 70 m（hereafter "the Hakozaki reconstruction" ; see Fig. II -2-3）. He based his theory on the miniature five-story pagoda of Gokurakubō（極楽坊） at Gangōji, which was made in the late Nara period. In the Hakozaki reconstruction, the miniature pagoda is enlarged to a scale that matches the ground floors of Tōdaiji's seven-story pagodas, and two stories are added to the top. He concluded the ground floors were five bays square based on historical documents and paintings. The Hakozaki reconstruction establishes a total height that is close to that of "just over 23 jō" found in historical records.
Chapter III: Excavation Findings
This chapter presents an overview of excavation findings（see Fig. III -1-1） and summarizes the baseline parameters for reconstructing the east pagoda. The standard unit of shaku used to build the Nara-period east pagoda was equal to 0.295 m. According to excavation data, the size of the stairs and the rammedearth platform（kidan 基壇） on which the building stood indicate the following: the ground floor was five bays square, the bay width（distance between the pillars） of the central bay was 12.0 shaku（3.54 m）, the width of other bays was 10.0 shaku（2.95 m）, and the total bay width（total length of one side） was 52.0 shaku （15.3 m; see Fig. III -2-4）. The standard unit of shaku used to build the Kamakura-period east pagoda was equal to 0.300 m. The holes left behind where pillar base stones were removed indicate the following: the ground floor in that period was three bays square, the bay width of the central bay was 20.0 shaku （6.0 m）, the bay width of the two side bays was 18.0 shaku（5.4 m）, and the total bay width was 56.0 shaku （16.8 m; see Fig. III -2-7）. Pebble beds for rainwater drainage were identified around the rammed-earth platforms for the pagodas built in the Nara and Kamakura periods. The locations of the roof eaves can be estimated from the placement of these pebble beds. Other artifacts useful for creating reconstructions were also excavated, including fragments of pillar base stones, roofing tiles, and tuff blocks and bricks used as paving materials（both including those shaped like isosceles triangles）. The width of concave roof tiles （hiragawara 平瓦） correlates to the space between tiles. It was slightly more than 1 shaku in the Nara period and slightly less than 1 shaku in the Kamakura period.
Chapter IV: Examining Pillar Base Stones and Determining Pillar Diameters
Fragments believed to be pieces of base stones from the Nara-period east pagoda were found during excavation（s see Fig. III -3-10（ 1） and Fig. IV -2-1）. The fragments were analyzed to determine the original sizes of the base stones. To estimate the diameter of the pillars that stood on them, we studied existing historical architecture to identify correlations between base stone size and pillar diameter. Applying these findings led to the conclusion that the pillar diameter used at the Nara-period east pagoda was 2.4 shaku （708 mm; see Fig. IV -4-1）.
We also examined stones alleged to be base stones taken from Tōdaiji's pagoda sites. The pillarbase stones at the sites of Tōdaiji's east and west pagodas no longer exist in situ and were likely removed during the modern era. Beginning in the late nineteenth century, it was a popular practice in Japan to procure base stones from historic temples to use as ornamental garden stones（keiseki 景石）, and Tōdaiji's base stones are thought to have been removed for that purpose. Gardens in Osaka, Yokohama, Nara, and other cities currently have ornamental stones traditionally believed to be base stones from Tōdaiji's pagodas. These stones were compared to excavated fragments of base stones and the archaeological features of the sites. Our findings confirmed that none of these stones were base stones from Tōdaiji's pagoda sites.
Chapter V: The Height of the Nara-Period East Pagoda of Tōdaiji
We reviewed historical records to determine the height of the east pagoda during the Nara period. We began by examining handwritten manuscripts, and discovered that no handwritten manuscript exists specifying the height of the east pagoda as 338.7 shaku（approx. 100 m; see Fig. V -6-1）. This figure was an error that arose when handwritten manuscripts were prepared for print publications. Handwritten manuscripts uniformly state the height of the east pagoda was 230.8 shaku（approx. 68 m）.
Next, we looked at historical documents that state the heights of extant historical pagodas. We were able to confirm that early historical records consistently included the finial in the heights they specified for pagodas, thus supporting Adachi Kō's understanding.
We concluded that the east pagoda's height including its finial was 230.8 shaku and proved there was no basis for claims that the total height was just over 30 jō. Further, historical records specify the height of the east pagoda's finial was 88.2 shaku（approx. 26 m）. Subtracting this from the total height yields a height of 142.6 shaku（42.1 m） for the pagoda body alone.
Chapter VI: Superstructure of the Nara-Period East Pagoda of Tōdaiji
We began creating a theoretical reconstruction after establishing baseline parameters using our findings in Chapters III through V. The proportion described in historical records of the finial making up 88.2 shaku of the pagoda's total height of 230.8 shaku may seem inordinately high. However, we concluded it is not improbable, as it is largely consistent with the proportions found in extant pagodas and works of art depicting pagodas（see Fig. VI -2-9）.
We then identified the ground plan, height, and structure of the ground floor. The pebble beds discovered during excavation allowed us to estimate the positions of the ends of the roof eaves（see Fig. VI -3-1）. We calculated the dimensions of the ground floor based on the size of the eave overhang （noki-no-de 軒の出; the distance from the exterior pillars to the ends of the eaves）. The results aligned with the dimensions and ground plan indicated in excavation findings, namely, five bays square with a central bay width of 12.0 shaku（3.54 m） and all other bay widths measuring 10.0 shaku（2.95 m）. We concluded that the framework（Jikubu 軸部） was primarily comprised of round pillars（maru-bashira 円柱）, headpenetrating tie-beams（kashiranuki 頭貫）, and wall plates（daiwa 台輪; see Fig. VI -3-41） based on the miniature five-story pagoda of Gokurakubō at Gangōji that was built at the end of the Nara period and other references. The height of the framework's main unit （the distance from the bottom of a pillar to the top of a wall plate） was calculated to be 14.0 shaku based on the size of the central bay. We determined the majority of the pagoda body height was made up of bracket complexes（kumimono 組物） placed atop pillars. To limit the pagoda body height to 142.6 shaku, it would have been necessary to keep the height of the bracket complexes as low as possible（see Fig. VI -3-42）. Further, bracket complexes changed substantially in different time periods, and we had to look at styles that predated the main hal（l kondō 金堂） at Tōshōdaij（i 唐 招提寺） and the miniature five-story pagoda of Gokurakubō at Gangōji, which were built at the end of the Nara period（see Fig. VI -3-34）. To that end, we examined Tōdaiji's Daibutsuden as an example of largescale architecture that was constructed before the east pagoda（see Appendix I）. Our findings were then reflected in the theoretical reconstruction of the east pagoda. Historical records confirmed the presence of curved eave struts（noki-shirin 軒支輪） on the Daibutsuden, allowing us to create a reconstruction for the Daibutsuden showing three-stepped bracket complexes（mitesaki kumimono 三手先組物） with curved eaves struts as the type of bracket complex used on the outermost pillars（see Fig. Appx. I -3-2）. Despite its large-scale, we did not believe the Daibutsuden used the four-stepped bracket complexes seen in earlier Chinese architecture. This led to the conclusion that the bracket complexes used in the east pagoda were also three-stepped bracket complexes with curved eaves struts, and that the longest purlin-bearing bracket arms（sane hijiki 実肘木） were 7.5 shaku（2.21 m; see Fig. VI -3-44）. Based on extant structures from the Nara period, we hypothesized that the intermediate supports placed between the bracket complexes （nakazonae 中備） were struts capped with bearing blocks（kentozuka 間斗束; see Fig. VI -3-53） and the eaves were double eaves（futanoki 二軒; see Fig. VI -3-63） using round base rafters and square flying rafters（jien hikaku 地円飛角） with closely spaced rafter intervals（shige-daruki 繁垂木）. The intervals between rafters were assumed to align with the intervals between roof tiles based on studies of Nara-period architectural miniatures and excavated materials from the eastern cloister（kairō 回廊） at Yamadadera（山田寺; see Fig. VI -3-60）. Roofing with alternately overlapping convex and concave roof tiles（hongawarabuki 本瓦葺） was determined to have been used based on excavated tiles, and the interval between tiles was set at 1.1 shaku. Based on studies of Nara-period architectural miniatures, we determined the roof to have one corner ridge （sumi-mune 隅棟）, without a second, shorter "offspring" ridge（chigo-mune 稚児棟） extending from it （see Fig. VI -3-66）. In our reconstruction, the beams that form the pillar bases（hashiraban 柱盤） for the exterior walls of the second story are placed on the ground floor's base rafters（ji-daruki 地垂木）. The resulting distance from the bottom of the large bearing blocks on top of the pillars on the ground floor to the top of the beams that form the second-story pillar bases is 14.0 shaku, and the total height of the ground floor is 28.0 shaku（when measured from the bottom of the exterior pillars to the top of the beams that form the second-story pillar bases）.
Next, we considered the dimensions and layout of the seventh story, the uppermost floor of the pagoda. Historical records specify the size of the finials atop Tōdaiji's seven-story pagodas. We hypothesized that the layout and dimensions of the uppermost floor would be related to the size of the finial and the method used to support it （see Fig. VI -5-8）. We identified correlations in extant historic pagodas between the size and layout of the uppermost floor and the size of the finial and method of supporting it and reflected our findings in the theoretical reconstruction. The results indicated the seventh story was three bays square with a central bay width of 10 shaku（2.95 m; see Fig. VI -5-14）. We estimated the total bay width of the seventh story should be between 26 and 28 shaku（7.67-8.26 m）.
We then estimated the layout, height, and structure of each story based on our previous research. Japanese pagodas are not designed to allow a person to ascend beyond the second story, and floors are not installed above it. Only the first floor has interior furnishings. We studied the characteristics of early pagodas to determine what kind of structure would be appropriate for the large-scale east pagoda. We placed the exterior pillars（gawa-bashira 側柱） and interior pillars（irigawa-bashira 入側柱） on pillar-base beams（hashiraban） atop the base hip rafters（ji-sumigi 地隅木） and base rafters（ji-daruki） of the floor below （see Fig. VI -4-10）. The four pillars（shiten-bashira 四天柱） surrounding the central pillar are placed on pillar-base beams laid across bracket tie beams（tsunagi-hijiki 繋肘木） connecting opposite sides of the floor below. Using the ground floor as our reference, we determined the framework of the stories from the second story up to have exterior pillar units made up of round pillars, head-penetrating tie-beams, and wall plates atop pillar-base beams, and all others were rendered as square pillars（kaku-bashira 角柱） atop pillar-base beams. The other features are largely identical to the ground floor.
We assumed the total bay width from the first to seventh story decreased a standard amount each story and expected individual bay widths to be a whole number of the shaku unit. Taking into account our estimation that the total width of the seventh story was between 26 and 28 shaku, we hypothesized that the width decreased by a uniform length of 4.0 shaku（1.18 m） per floor（see Table VI -6-3）. Following this calculation, the total bay width of the seventh floor was set at 28.0 shaku. The resulting width of the seventh floor is 53.8% of that of the ground floor. We set the minimum width between pillars to 8.0 shaku（2.36 m） to accommodate the length of the longest purlin-bearing bracket arms（7.5 shaku; see Fig. VI -6-15）. When a floor's estimated dimensions could no longer accommodate this value（8.0 shaku） as the minimum length between pillars, we reduced the number of pillars and bays for that floor. As a result, the ground floor through fourth story were calculated to be five bays square, the fifth and sixth stories were four bays square, and the seventh story was three bays square（see Fig. VI -6-18）. Based on extant historical pagodas, we estimated the height of the second story to be seven-tenths of that of the ground floor, and the uppermost story to be two-thirds of that of the ground floor. This resulted in the height of the second story being 19.6 shaku（5.78 m） and that of the seventh story being 18.6 shaku（5.49 m; see Fig. VI -6-11）.
For bay fittings on the ground floor, we selected outward-opening plank doors（ita-tobira 板扉） for the three central bays spanning the width of the stairs. The remaining two bays on either end were fitted with grill windows with vertical railings（renjimado 連子窓）. We hypothesized that the upper stories had bay fittings related to those on the ground floor and placed renjimado on the bays on either end and inwardopening plank doors on the other bays. Historical records support this choice, as they state the east pagoda was furnished with renjimado. We reconstructed the railings around the rammed-earth platform（kidan） and upper stories based on early architecture, paintings, and similar references. We chose to make them straight （level） railings（kumi-kōran 組高欄） without curved rails projecting beyond the corner posts（see Fig. VI -7-7）. For the upper stories, we selected railings that did not have openings in the middle（see Fig. VI -7-8）.
We based the reconstruction of the raised platform forming the central altar （butsudan 仏壇） on bricks excavated from the site and records saying it was faced with blocks of tuff（see Fig. VI -7-10）. Following the style of the rammed-earth platform（kidan）, we adopted a formal type of podium constructed of cut stones（danjōzumi 壇正積） for the facing of the central altar and used dressed blocks of tuff as cladding. We posited that the top of the altar space was paved with square bricks laid on the diagonal （shihanjiki 四半敷） and the altar space was surrounded by a straight railing（kumi-kōran; see Fig. VI -7-12）. Referencing early pagodas, we hypothesized that a podium representing the sacred Buddhist mountain Sumeru（shumisen 須 弥山） was placed in the center of the central altar to hide the central pillar （shin-bashira 心柱）. We made the central altar a square. Based on the size of the central pillar and the additional space needed to enshrine Buddhist statues, we believe the central altar must have stretched beyond the four pillars surrounding the central pillar. This made identifying the positions of base stones for central pillar and four surrounding pillars problematic, because they were covered by the central altar. Referencing changes in the position of the base stone for the central pillar in early pagodas over time, we hypothesized that the base stones for the central pillar and four surrounding pillars were set on top of the rammed-earth platform. Consequently, the lower sections of the central pillar and four surrounding pillars would have been hidden in the central altar's masonry.
We referenced historic architecture to reconstruct the ceilings. For the ground floor, we installed a lattice ceiling（kumiire-tenjō 組入天井） on the second tier of bracket arms（ni-no-hijiki 二の肘木; see Fig. VI -7-15 left）. To accommodate this, we built small walls between the wall plates visible in the interior and the second tier of bracket arms.
We reconstructed the flooring based on samples of tuff recovered during excavations. We gave the ground floor a dirt floor paved in square tuff bricks laid on the diagona（l shihanjiki; see Fig. I -3-3）. We posited that the top of the rammed-earth platform（kidan） was also paved in square tuff bricks laid on the diagonal.
We reconstructed the pagoda's exterior ornamental metal fittings and coloring based on excavated materials, historical records, paintings, and extant historic architecture. We made the walls white, the wooden components red, and the window railing（s renjiko 連子子） green（see［ Main Report］ frontispiece）
Chapter VII: Evaluation of Structural Analysis of the Nara-Period East Pagoda of Tōdaiji
Structural analysis of the theoretical reconstruction of the Nara-period east pagoda was conducted to determine if it was structurally viable and would not collapse under its own weight during construction or upon completion. The analysis focused on architectural members that would bear the heaviest loads, namely, the framework（Jikubu）, bracket complexes（kumimono）, and eaves. We first calculated the stresses each of these members would be subjected to. To evaluate the results, we then conducted structural analysis of the extant five-story pagoda at Kōfukuj（i 興福寺） and compared it with the structural analysis results for Tōdaiji's east pagoda. The structural analysis data is appended to this repor（t see［ Figures and Structural Analysis Materials］）.
Our findings indicate the theoretical reconstruction of the east pagoda is structurally viable and the building would not have collapsed under its own weight during construction or upon completion.
Chapter VIII: Superstructure of the Kamakura-Period East Pagoda of Tōdaiji
We created theoretical reconstructions of the east pagoda that was rebuilt during the Kamakura period to assist in developing a theoretical reconstruction of the Nara-period east pagoda. However, the primary focus of this research was the Nara-period east pagoda and the theoretical reconstructions of the Kamakura-period east pagoda are only intended to offer a rough understanding of its overall appearance. We did not attempt to reconstruct the building in detail.
The Nara-period east pagoda burned down in 1180. Its reconstruction in the early Kamakura period （ca. 1200） was initially led by the monk Chōgen（1121-1206; 重源）. However, Chōgen died before the pagoda could be completed and was replaced by the monk Eisai （1141-1215; or Yōsai栄西）. The finial of the Kamakura-period east pagoda was assembled in 1223, and the structure was officially completed shortly thereafter.
As a result, we created two theoretical reconstructions of the Kamakura-period east pagoda. We did this because Chōgen and Eisai/Yōsai are known to have constructed buildings in distinct architectural styles, and it was not possible to determine which of their designs had been used for the east pagoda. We named them the "Chōgen reconstruction" and the "Eisai/Yōsai reconstruction." Chōgen built Tōdaiji's Great South Gate（Nandaimon）, which is now an iconic example of architecture in the Great Buddha style（Daibutsuyō 大仏様）. The only extant building constructed by Eisai/Yōsai is Tōdaiji's belfry, which combines elements of the Great Buddha style, Zen style（Zenshūyō 禅宗様）, and a traditional Japanese architectural style that predates the Heian period, known as Wayō（和様）.
Dimensions and Forms Common to the Chōgen and Eisai/Yōsai Reconstructions
We identified the dimensions and forms that would have been the same in the Chōgen and Eisai/Yōsai reconstructions. For the Kamakura-period pagoda, we were able to determine the plan and dimensions of the ground floor during excavations（see Chapter III）, and a total height of 32 jō（96 m） is specified in historical records. The height of the finial is unknown. We assumed the same height as the Naraperiod east pagoda finial. Doing this yields a finial height of 26 m and a pagoda body height of 70 m. We modeled the finial's design on the one seen in the five-story pagoda of Kaijūsenj（i 海住山寺）, which largely retains its original materials from when it was built in the Kamakura period（see Fig. VIII -2-4 and 5）. We estimated the width of the seventh story would be close to 70% of that of the ground floor, as seen in extant pagodas from the Kamakura period. Based on this ratio and similar data, we determined all stories of the pagoda were three bays square. Historical records indicate that pillars were erected separately for the ground floor and the second story. Thus, we concluded pillars were erected on each floor, without the use of pillars rising through multiple stories（tōshi-bashira 通し柱）. Roofing with alternately overlapping convex and concave roof tiles（hongawarabuki） was selected based on excavated tiles, and we set the interval between tiles at 1.0 shaku. Only one type of ridge-end roof tile（onigawara 鬼瓦） was found during excavation, leading us to conclude the roof used only single corner ridges（sumi-mune）, without second, shorter "offspring" ridges（chigo-mune） extending from them（see Fig. VIII -2-2 and 3）.
The Chōgen Reconstruction
We created the Chōgen reconstruction largely in reference to Tōdaiji's Nandaimon（see Fig. VIII -3-2）. In the Chōgen reconstruction, the total width of the bays decreases by 3.0 shaku（0.90 m） per story to make the total bay width on the seventh story 38.0 shaku（11.40 m; see Table VIII -3-3）, a width close to 70% of that of the ground floor. The precise ratio in this case is 67.9%.
We based the framework（Jikubu） on Tōdaiji's Nandaimon. We used only round pillars and laid transverse, double-tier "rainbow" beams（kōryō 虹梁） across the large bearing blocks（daito） atop the pillars （see Fig. VIII -3-4 and 5）. We based the structure of the rainbow beams on extant examples seen in Great Buddha style architecture using rainbow beams and bottle struts（taiheizuka 大瓶束; see Fig. VIII -3-3）. For the lower rainbow beams, we first placed two large rainbow beams（daikōryō 大虹梁） parallel to each other across the four central pillars. The large rainbow beams are the same height and cannot bisect each other. We placed smaller rainbow beams across the side bays that bisect the large rainbow beams and inserted them into the sides of the large rainbow beams. We also laid rainbow beams in the directions of the corners. These make up the lower tier of rainbow beams. Two large rainbow beams are placed atop the lower ones at a perpendicular angle to hold the four central pillars of the next story. The bases of the four central pillars are carved to straddle the curved surfaces of the large rainbow beams like bottle struts. The upper tier of rainbow beams is made up of only two large parallel rainbow beams.
For bracket complexes, the Chōgen reconstruction uses six-stepped bracket complexes with penetrating bracket arms（sashi-hijiki 挿肘木; see Fig. VIII -3-7）, as seen in Tōdaiji's Nandaimon. There are no intermediate supports（nakazonae） between bracket complexes. The eaves were modeled on those of Tōdaiji's Nandaimon and comprise single eaves（hitonoki 一軒） with fan rafters that radiate toward the hip rafters at the corners（sumi-ōgi-daruki 隅扇垂木） and have an eave curve（nokizori 軒反り）. Fascia boards （hanakakushi-ita 鼻隠板） are placed at the ends of the rafters. Following extant examples of Great Buddha style architecture, there are no ceilings. Drawing on historic developments seen in extant pagodas, we set a low wooden floor on the ground floor.
As seen in Tōdaiji's Nandaimon and other temple halls in the Great Buddha style, the central bay of the ground floor has outward-opening, Chinese-style paneled entrance doors（sankarado 桟唐戸） and the two side bays have grill windows with vertical railings（renjimado）. On the upper stories, the central bays have inward-opening plank doors with battens（ita-sando 板桟戸）, and the two side bays are fitted with partitions made of horizontal planks（yokoita-kabe 横板壁）. Like Tōdaiji's Nandaimon, there are no railings.
The Eisai/Yōsai Reconstruction
The Eisai/Yōsai reconstruction is primarily based on Tōdaiji's belfry（see Fig. VIII -4-16）. However, characteristics unique to suspending the bell, such as the thickness of the penetrating tie beams, were not replicated. A distinct feature of the bracket complexes in Tōdaiji's belfry is that the small bearing blocks （makito 巻斗） are flush-aligned, with no space in between（see Fig. VIII -4-5）. For that reason, the width of the makito is the standard unit of measurement for the structure. All other dimensions are designed to be multiples of that width, including bay widths and the eave overhang（noki-no-de; see Fig. VIII -4-1）. We followed that method of design in the Eisai/Yōsai reconstruction, and based the dimensions of each component on the makito width. Using an estimated pillar diameter extrapolated from the bay width and the makito width, we made the dimensions of the components in the Eisai/Yōsai reconstruction 1.6 times larger than those in Tōdaiji's belfry. The makito width in the Eisai/Yōsai reconstruction is 1.25 shaku（375 mm; see Fig. VIII -4-13）.
The central bay width of 20.0 shaku on the ground floor is 16 times the makito width. However, the width of the side bays is 18.0 shaku and is not a multiple of the makito width（1.25 shaku x 14 = 17.5 shaku; approx. 5.25 m）. As a result, we added intervals between the makito in the side bays to make the bay widths 18.0 shaku（see Fig. VIII -4-8）. It would have been possible to set the widths of the side bays at 14 times the makito width, because the exterior pillars would still line up with the holes for their base stones, but we decided to adhere to the width of 18.0 shaku that was indicated in excavation findings. The bay widths on the upper stories are even multiples of the makito width.
To reduce the width of the uppermost story to 70% of that of the ground floor, we reduced the total bay width for each story by 2 makito widths, or 2.5 shaku（0.75 m; see Table VIII -4-2）. This made the total bay width for the seventh story 40.0 shaku, or precisely 71.4% of that of the ground floor.
Following the framework（Jikubu） of Tōdaiji's belfry, all the pillars on the ground floor are round and the exterior pillars are pierced with penetrating tie beams at their bases（jinuki 地貫）, by mid-wall penetrating tie-beams（uchinori-nuki 内法貫）, and by head-penetrating tie beams（kashiranuki）. We added carved molding decoration to the ends of each of the penetrating tie beams in the Great Buddha style. The four central pillars on the ground floor are pierced with head-penetrating tie beams only. The framework （Jikubu） of the upper stories has exterior pillar units comprised of pillar-base beams（hashiraban）, round pillars, and head-penetrating tie beams. The ends of the head-penetrating tie beams have Great Buddhastyle carved molding decoration. The four central pillars on the upper stories are comprised of pillar-base beams, square pillars, and head-penetrating tie beams.
The bracket complexes follow those of Tōdaiji's belfry and are four-stepped with flush-aligned makito（see Fig. VIII -4-14）. Intercolumnar bracket complexes（tsumegumi 詰組） are used as intermediate supports（nakazonae） and are similar to the bracket complexes used atop pillars. The eaves are also based on Tōdaiji's belfry. The reconstruction has double eaves（futanoki） with closely spaced rafter intervals （shige-daruki） and an eave curve（nokizori）. Fascia boards（hanakakushi-ita） are placed at the ends of the flying rafters（hien-daruki 飛檐垂木）.
The fittings in the bays follow Zen-style pagodas. The ground floor's central bay has outwardopening Chinese-style paneled entrance doors（sankarado） and the side bays have stylized, arched windows（katōmado 火灯窓）. On the upper stories, stylized, arched doors（katōguchi 火灯口） are placed in the central bays and renjimado are used for the side bays. Based on extant pagodas, we placed railings on the upper stories of the Eisai/Yōsai reconstruction（see Fig. VIII -4-27）. The railings have newel posts topped with lotus-shaped decorations and open in the center, as seen in railings with Zen-style elements on the three-story pagoda at Kōjōj（i 向上寺; see Fig. VIII -4-29）. The same railing is installed around the rammed-earth platform（kidan）. To prevent each story's pillars from looking too long, additional bracket complexes（koshigumi 腰組） were placed under the railings in the Eisai/Yōsai reconstruction（see Fig. VIII -4-31 and 32）.
Chapter IX: Conclusion
This chapter reviews and summarizes the study's findings, explains their significance, and identifies topics for future research. The study's findings were summarized in the preceding sections. The significance of its findings and topics for future research are discussed below.
Significance of Research Findings
The Nara-Period East Pagoda
Tōdaiji's seven-story pagodas built in the Nara period were previously believed to have a total height close to 100 meters. However, using an interdisciplinary approach that combined history and architectural history, we established the total height was instead closer to 70 meters. The ground floor plan was thought to be three bays square but our excavations revealed it was five bays square. Our study used the existing Hakozaki reconstruction as its starting point, but differed from previous research by re-examining materials that served as the basis for claims concerning the external appearance of the pagoda, namely, the ground floor plan and total height, and by re-establishing the pagoda's baseline parameters after verifying the accurate content of historical materials. This study also expanded on past research by incorporating new knowledge from recent conservations of similar extant buildings.
Historical research often draws on publications that have been reprinted or edited, but we were able to review handwritten manuscripts in this study. That allowed us to find discrepancies between the original manuscripts and later printed editions. These are significant findings in the field of history, as they highlight the importance of examining primary sources when conducting historical research as well as the importance of using proper methods when editing and reprinting.
Our study concluded that the ground floor was five bays square and the total height of the pagoda was 70 m（see ［Main Report］ frontispiece, Fig. 1 to 15 and Fig. VI -9-1）. As discussed in the Hakozaki reconstruction, the ground floor comprises a greater percentage of the total height than seen in extant multistoried pagodas. Further, the size of the eave overhang（noki-no-de） is small, meaning the pagoda would have had a somewhat "plump" appearance. There was no extra space in which to add decorative elements, like pent roof enclosures（mokoshi 裳階） or additional bracket complexes（koshigumi）. This study offers significant findings in the field of architectural history for identifying the ground floor plan and total height of an early example of a now-lost seven-story pagoda and for fundamentally changing the way it is perceived.
The pagoda body height and its relationship to other architectural members indicated the bracket complex style was older than that used in the main hall （kondō 金堂） of Tōshōdaiji and the miniature fivestory pagoda of Gokurakubō at Gangōji and that the eaves had an extremely shallow slope. These results fill a gap in architectural history by identifying early architectural techniques and their developments in the period between the construction of the east pagoda at Yakushij（i 薬師寺） in 730 and the main hall of Tōshōdaiji at the end of the Nara period（late eighth century）.
Tōdaiji's seven-story pagodas built during the Nara period have been a standard reference for conceptualizing historic seven-story pagodas that no longer exist, particularly because the heights of Tōdaiji's pagodas were thought to be known. We corrected basic data concerning Tōdaiji's pagodas, which raises the need to re-evaluate theoretical reconstructions based on them. Further, Tōdaiji was the head temple（sōkokubunji 総国分寺） of a system of state-sponsored provincial temples（kokubunji 国分寺）, and its pagodas would have been models for other temples. Notably, the majority of the theoretical reconstructions of pagodas for state-sponsored provincial temples appear to have been based on the Amanuma reconstruction and will have to be fundamentally re-examined（see Fig. IX -3-1 to 3）. This constitutes a significant finding in the field of architectural history. In addition to adding to our understanding of the Nara-period east pagoda at Tōdaiji, the finding impacts all the theoretical reconstructions of historic pagodas that were modeled on previous understandings.
The objective of this research was to create a theoretical reconstruction of the Nara-period east pagoda at Tōdaiji, but in the process, we uncovered many new findings concerning early pagodas and Buddhist halls. These discoveries are expected to contribute to future advances in architectural history. The Kamakura-Period East Pagoda The east pagoda that was rebuilt during the Kamakura period had not previously been studied. This study is the first to examine them. We created two theoretical reconstructions, the Chōgen reconstruction and the Eisai/Yōsai reconstruction（see Fig. 16 to 19, Fig. VIII -6-1 and 2）. This study's findings could serve as a starting point for future research, as they offer an important first look at architecture that is no longer extant in the Great Buddha style and early Zen style.
Through excavations, we determined the ground floor plan of the Kamakura-period east pagoda was three bays square, and historical records indicate its total height was 96 meters. These features differ from those of the Nara period. Further, the distance between the pillars on the ground floor was significantly widened, and the height of the ground floor was increased. Consequently, the total height of the pagoda was also increased. The modifications to the ground floor plan and total height indicate there was a major change in architectural style when the pagoda was rebuilt.
We created theoretical reconstructions of the Kamakura-period east pagoda as preliminary research for reconstructing the Nara-period east pagoda. This process revealed changes in the pagoda's structure between the Nara and Kamakura periods. These findings are important, as they offer insights into aspects of Tōdaiji's reconstruction during the Kamakura period that differ from conventional understandings.
The monk Chōgen led Tōdaiji's reconstruction during the Kamakura period. He received an imperial edict that indicated the temple's precincts were to be reconstructed as they were built in the Nara period and that their original layouts were to be retained. The changes we discovered in the east pagoda precinct suggest reconstruction decisions differed from the edict's specifications and existing understandings.
Future Research
This study focused on the Nara-period east pagoda. Topics for future research are discussed below.
First, the east pagoda precinct presumably included gates and cloisters（kairō） in addition to the east pagoda. This study was only concerned with the east pagoda and did not take into account the pagoda's relationship to the east pagoda precinct in its entirety, including its gates and cloisters. This is a topic for future research.
Further, this study primarily referenced pagodas and historical records that exist in Japan. Research on pagodas and historical materials from East Asia remains inadequate and should be taken up in future research.
Although the study used an interdisciplinary approach combining architectural history, archaeology, and history, the fields of art history and Buddhist history were not sufficiently incorporated. In particular, much research remains to be done on the central altar that made up the interior of the ground floor and other interior and exterior decorative elements, including colors, motifs, and plaques.
Reports were published following recent conservation of historic pagodas, including the east pagoda of Yakushiji and the west pagoda of Taimadera（当麻寺）. Conservation is currently underway for the large-scale five-story pagoda at Kōfukuji. These projects are producing new discoveries concerning early pagodas and large-scale pagodas. In the future, we expect this research to be updated to reflect new findings. Existing theoretical reconstructions of pagodas of state-sponsored provincial temples（kokubunji） should also be updated pursuant to this study's findings.
To achieve this study's primary objective, we created theoretical reconstructions of the Kamakuraperiod east pagoda but did not study the building in detail. Further, our research on the Nara-period east pagoda was only to the extent that a model could be created. The research scope did not include construction methods or other details necessary to create a full-scale reconstruction.
Appendix I: The Nara-Period Daibutsuden's Pent Roof Enclosure（Mokoshi） and Surrounding Elements
Although lost to a fire in 1180, Tōdaiji's original Daibutsuden was built during the Nara period（ca. 752）. As a building made on the same premises in the same period（see Fig. Appx. I -1-1）, we believed it would be a useful reference for making a theoretical reconstruction of the east pagoda. In particular, historical records describe the bracket complexes used in its pent roof enclosure（mokoshi）. We focused our study on this part of the structure and created a reconstruction drawing（see Fig. Appx. I -3-2）. In our reconstruction,the ground floor has an inner core（moya 身舎） seven bays wide by three bays deep, an aisle（hisashi 廂） extending one-bay deep on all four sides, and a pent roof enclosure extending one-bay deep on all four sides. In its entirety, the ground floor is consequently eleven bays wide by seven bays deep. In this report, the moya and hisashi together are referred to as shuoku（主屋; see Fig. Appx. I -2-3）.
Appendix II: Miscellaneous Research
Other subjects of the preliminary research we conducted to create a theoretical reconstruction of Tōdaiji's east pagoda included: pillar-base stones across Japan that were allegedly taken from Tōdaiji, historic architectural materials owned by Tōdaiji, and architectural drawings of Gangōji's five-story pagoda（destroyed by a fire in 1859; see Fig. 43 and Fig. Appx. II -3-1）, which was referenced as a potentially similar structure. In the end, these studies did not produce information pertinent to creating a theoretical reconstruction of Tōdaiji's east pagoda. However, we eliminated the possibility of using these sources and narrowed the breadth of our reference materials. Our research resulted in individual findings pertinent to other fields of research.
Appendix III: Structural Evaluations
Appendix III uses structural analysis data（see［Figures and Structural Analysis Materials］） to calculate the stress distribution characteristics of Kōfukuji's five-story pagoda, the original reconstruction we made of the Nara-period east pagoda, and a variant reconstruction we made with inner pillars（naibu hashira 内部柱; see Fig. VI -4-11）. Comparing the stress distributions of each structure resulted in a better understanding of the characteristics of our original reconstruction and allowed us to identify how they would change in the variant reconstruction with inner pillars.
Notably, we found the interior pillars（irigawa-bashira） would be subject to enormous compressive force in the original reconstruction we made for the Nara-period east pagoda, which has a ground floor five bays square（see Fig. Appx. III -2-2）. This indicates that, for large-scale, multistoried pagodas with a diminishing number of bays in ascending stories, the distribution of weight along the interior members that support the structure is more important than forces exerted on the external pagoda body, which has more often been the focus of past research. Further, we confirmed that making the ground floor five bays square is an effective strategy for supporting the structure's weight, because it distributes compressive forces among the pillars, including the four pillars surrounding the central pillar on the ground floor. We confirmed that the variant reconstruction with inner pillars for the Nara-period east pagoda would tend to distribute the load more evenly among architectural members than the original reconstruction and reduce stress concentrations.
Appendix IV: Reference Drawings
As instructed by the advisory committee, we created reference drawings of theoretical reconstructions of the Daibutsuden and east pagoda constructed in the Nara period（see Fig. Appx. IV -1-1 to 3, Fig. Appx. IV -2-20 and 21）. We received instructions to make drawings for alternate styles of bracket complexes and drawings of the Nara-period east pagoda with a total height of 32 jō（approx. 100 m）.
Through the creation of these drawings for the Nara-period east pagoda, we verified that a pagoda with a total height of 32 jō（approx. 100 m） and a ground floor five bays square（with a total bay width of 52.0 shaku = 15.34 m）, would have needed specially designed elements to increase the height, including bracket complexes, eaves, and railings, and could not have been made without additional bracket sets（koshigumi）. Even with these modifications, the pagoda body would have been narrow compared to the size of the ground floor, probably causing the pagoda to appear unbalanced. Creating the reference drawings resulted in important findings, as they allowed us to validate the feasibility of the Nara-period east pagoda's theoretical reconstruction（total height of 230.8 shaku = approx. 68 m）.
Other Notes
This report is appended by additional volumes of ［Figures and Structural Analysis Materials］. Figures include theoretical reconstructions from this study as well as previous theoretical reconstructions and other visual materials（excavation drawings, historical records, paintings, and drawings of similar buildings）. The volume of structural analysis materials includes documents prepared by Bunkenkyo and Tateishi Kōzō Sekkei.
2024年3月29日 発行
奈良文化財研究所学報 第104冊
