| CHAPTER I. |
| INTRODUCTION—GIRDER BEARINGS. |
| PAGE |
| Pressure distribution—Square and skew bearings—Fixed bearings—Knuckles—Rollers—Yield of supports | 1 |
| CHAPTER II. |
| MAIN GIRDERS. |
| Plate webs: Improper loading of flanges—Twisting of girders—Remedial measures—Cracks in webs—Stiffening of webs—T stiffeners | 9 |
| Open webs: Common faults—Top booms—Buckling of bottom booms—Counterbracing—Flat members | 17 |
| CHAPTER III. |
| BRIDGE FLOORS. |
| Liability to defects—Impact—Ends of cross and longitudinal girders—Awkward riveting—Fixed ends to cross girders—Plated floor—Liberal depths desirable—Type connections—Effect of “skew” on floor—Water-tightness—Drainage—Timber floors—Jack arches—Corrugated sheeting—Ballast—Rail joints—Effect of main girders on floors | 20 |
| CHAPTER IV. |
| BRACING. |
| Effect of bracing on girders—Influence of skew on bracing—Flat bars—Overhead girders—Main girders stiffened from floor—Stiffening of light girders—Incomplete bracing—Tall piers—Sea piers | 34 |
| CHAPTER V. |
| RIVETED CONNECTIONS. |
| Latitude in practice—Laboratory experiments—Care in considering practical instances—Main girder web rivets—Lattice girders investigated—Rivets in small girders—Faulty bridge floor—Stresses in rivets—Cross girder connections—Tension in rivets—Defective rivets—Loose rivets—Table of actual rivet stresses—Bearing pressure—Permissible stresses—Proposed table—Immunity of road bridges from loose rivets—Rivet spacing | 45 |
| CHAPTER VI. |
| HIGH STRESS. |
| Elastic limit—Care in calculation—Impact—Examples of high stress—Early examples of high stress in steel girders—Tabulated examples—General remarks | 61 |
| CHAPTER VII. |
| DEFORMATIONS. |
| Various kinds—Flexing of girder flanges—Examples—Settlement deformations—Creeping—Temperature changes—Local distortions—Imperfect workmanship—Deformation of cast-iron arches | 73 |
| CHAPTER VIII. |
| DEFLECTIONS. |
| Differences as between new work and old—Influence of booms and web structure on deflection—Yield of rivets and stiffness of connections—Working formulÆ—Set—Effect of floor system—Deflection diagrams—Loads quickly applied—“Drop” loads—Flexible girders—Measuring deflections—New method of observing deflections—Effect of running load | 85 |
| CHAPTER IX. |
| DECAY AND PAINTING. |
| Examples of rusting of wrought-iron girders—Girder over sea-water—Rate of rusting—Steelwork—Precautions—Red-lead—Repainting—Scraping—Girders built into masonry—Cast iron—Effect of sea-water on cast iron—Examples—Tabulated observations—Percentage of submersion—Quality of metal | 96 |
| CHAPTER X. |
| EXAMINATION, REPAIR, AND STRENGTHENING OF RIVETED BRIDGES. |
| Purpose—Methods of examination—Calculations—Stress in old work—Methods of reducing stress—Repair—Loose rivets—Replacing wasted flange plates—Adding new to old sections—Principles governing additions—Example—Strengthening lattice girder bracings—Bracing between girders—Strengthening floors—Distributing girders | 107 |
| CHAPTER XI. |
| STRENGTHENING OF RIVETED BRIDGES BY CENTRE GIRDERS. |
| Principal methods in use—Method of calculation—Adjustments—Connections—Method of execution—Checks—Effect of skew on method considered—Results of calculation for a typical case—Probable error—Practical examples—Special case—Method of determining flexure curves | 122 |
| CHAPTER XII. |
| CAST-IRON BRIDGES. |
| Limitations of cast iron—Stress examples—Advantages and disadvantages—Foundry stresses—Examples—Want of ductility of cast iron—Repairs—Restricted possibilities | 141 |
| CHAPTER XIII. |
| TIMBER BRIDGES. |
| Perishable nature—Causes of decay—Sag—Lateral bracing—Piles—Uncertainty respecting decay—Examples—Conditions and practice favourable to durability—Bracing—Protection—Repair—Piles—Cost | 149 |
| CHAPTER XIV. |
| MASONRY BRIDGES. |
| Definition—Cause of defects or failure—Spreading of abutments—Closing in—Example—Stop piers—Example of failure—Strength of rubble arch—Equilibrium of arches—Effect of vibration on masonry—Safety centring—Methods of repair—Pointing—Rough dressed stonework | THE
ANATOMY OF BRIDGEWORK.
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