Chapter I: Preface: To the Sixth Edition

During the few years that have elapsed since the publication of the first edition of this work, the art of tunneling through different soils and especially under large bodies of water, has made considerable progress. During the last ten years, no less than eight subaqueous tunnels involving the construction of sixteen tubes have been constructed for the service of the city of New York alone. The reader will, no doubt, also recall the tunnels under the Boston Harbor, the St. Clair, the Charles and Detroit Rivers in our own country as well as the tunnels under the Thames and the Seine in Europe. Engineers, contractors and workmen have acquired such experience in these difficult underground and under-river construction that the work is now undertaken without any of the fear and hesitation that were associated with the earlier enterprises.

As entirely new methods have been introduced by professional men, it was found necessary to arrange the presentation of the subject in this sixth edition so as to give due prominence to these recent methods.

Besides this, other changes have been made in order to give greater attention to American method of excavating tunnels through rock and loose soil. This will explain the treatment of the crown-bar and also the extensive illustration of the heading and bench method as well as the drift method of driving tunnels which is followed in the United States.

Space has also been given to important tunnels recently built mainly for the purpose of illustrating the various methods discussed in the text and also to bring out more clearly the characteristics of the different methods of tunnel excavation.

The author hopes that these added features will meet the present requirements of engineers and students.

CHARLES PRELINI.

MANHATTAN COLLEGE,
NEW YORK CITY.

CONTENTS

PAGE

INTRODUCTORY--THE HISTORICAL DEVELOPMENT OF TUNNEL BUILDING xiii

CHAPTER

I. PRELIMINARY CONSIDERATIONS; CHOICE BETWEEN A TUNNEL AND AN
OPEN CUT; GEOLOGICAL SURVEYS 1

II. METHODS OF DETERMINING THE CENTER LINE AND FORMS AND
DIMENSIONS OF CROSS-SECTION 9

III. EXCAVATING MACHINES AND ROCK DRILLS; EXPLOSIVES AND
BLASTING 22

IV. GENERAL METHODS OF EXCAVATION; SHAFTS; CLASSIFICATION OF
TUNNELS 36

V. METHODS OF TIMBERING OR STRUTTING TUNNELS 47

VI. METHODS OF HAULING IN TUNNELS 59

VII. TYPES OF CENTERS AND MOLDS EMPLOYED IN CONSTRUCTING TUNNEL
LININGS OF MASONRY 66

VIII. METHODS OF LINING TUNNELS 72

IX. TUNNELS THROUGH HARD ROCK; GENERAL DISCUSSION;
REPRESENTATIVE MECHANICAL INSTALLATIONS FOR TUNNEL WORK 84

X. TUNNELS THROUGH HARD ROCK (_continued_); EXCAVATION BY
DRIFTS; THE SIMPLON AND MURRAY HILL TUNNELS 102

XI. TUNNELS THROUGH HARD ROCK (_continued_); EXCAVATION BY
HEADINGS 130

XII. EXCAVATING TUNNELS THROUGH SOFT GROUND; GENERAL
DISCUSSION; THE BELGIAN METHOD 143

XIII. THE GERMAN METHOD--EXCAVATING TUNNELS THROUGH SOFT GROUND
(_continued_); BALTIMORE BELT LINE TUNNEL 155

XIV. THE FULL SECTION METHOD OF TUNNELING; ENGLISH METHOD;
AMERICAN METHOD; AUSTRIAN METHOD 166

XV. SPECIAL TREACHEROUS GROUND METHOD; ITALIAN METHOD;
QUICKSAND TUNNELING; PILOT METHOD 182

XVI. OPEN-CUT TUNNELING METHODS; TUNNELS UNDER CITY STREETS;
BOSTON SUBWAY AND NEW YORK RAPID TRANSIT 195

XVII. SUBMARINE TUNNELING; GENERAL DISCUSSION; THE SEVERN TUNNEL 218

XVIII. SUBMARINE TUNNELING (_continued_); THE COMPRESSED AIR
METHOD; THE MILWAUKEE WATER-WORKS TUNNEL 225

XIX. SUBMARINE TUNNELING (_continued_); THE SHIELD SYSTEM 238

XX. SUBMARINE TUNNELING (_continued_); THE SHIELD AND
COMPRESSED AIR METHOD; THE HUDSON RIVER TUNNEL OF THE
PENNSYLVANIA RAILROAD 263

XXI. SUBMARINE TUNNELING (_continued_); TUNNELS AT VERY SHALLOW
DEPTH; THE COFFERDAM METHOD; THE PNEUMATIC CAISSON METHOD;
THE JOINING TOGETHER SECTIONS OF TUNNELS BUILT ON LAND 281

XXII. ACCIDENTS AND REPAIRS IN TUNNELS DURING AND AFTER
CONSTRUCTION 301

XXIII. RELINING TIMBER-LINED TUNNELS WITH MASONRY 315

XXIV. THE VENTILATION AND LIGHTING OF TUNNELS DURING
CONSTRUCTION 325

XXV. THE COST OF TUNNEL EXCAVATION AND THE TIME REQUIRED FOR
WORK 336

LIST OF ILLUSTRATIONS

FIGURE PAGE

1. Diagram Showing Manner of Lining in Rectilinear Tunnels 10

2. B. R. Value’s Device for Locating the Center Line Inside of
a Tunnel 11

3. Triangulation System for Establishing the Center Line of the
St. Gothard Tunnel 12

4. Method of Transferring the Center Line down Center Shafts 13

5. Method of Transferring the Center Line down the Side Shafts 14

6. Method of Laying out the Center Line of Curvilinear Tunnels 15

7. Diagram of Polycentric Sectional Profile 19

8, 9 and 10. Typical Sectional Profiles for Tunnel 20

11. Soft Ground Bucket Excavating Machine; Central London
Underground Railway 22

12. Column Mounting for Percussion Drill; Ingersoll Sargent Drill
Co. 26

13. Sketch of Diamond Drill Bit 27

14. Diagram Showing Sequence of Excavation for St. Gothard
Tunnel 36

15. Diagram Showing Manner of Determining Correspondence of
Excavation to Sectional Profile 38

16. Polar Protractor for Determining Profile of Excavated Cross-