Records,

unit costs, 385

weights of lift bridges, 297

"Red Lead Lute," 432

Red lead,

paint for shop coat, 431

proportion of, in paint, 434

Red Oxide No. 31, 432

Red Rock Cantilever Bridge,

designing of piers for, 167

Reduced live loads for combined

bridges, 132

Reducing-gear, hydraulic, 313

Reduction of voids in the aggregate, 389

Reichmann, Albert, 214

Reinforced-concrete,

bridges,

arch bridges, 225-230

economics of, 218

life of, 64

limiting span-length of, 66

small cost of maintenance

and repairs for, 64

caissons, 169

columns, 223

girders, 221, 223-225

pier-shafts, 167

piles, 225

piles versus wooden piles, 174

steel structures, 64

trestles for steam railways, 230

trestle versus steel trestle, 114

versus plain concrete for pedestal

bases, 173

viaducts, water-proofing for, 454

Reinforcing bars, high-carbon steel for,

133

Reinforcing steel, 218

Repainting, determination of time for, 445

Repairs, 124

economics of, 407-429

renewals, equipment for, 420

stone masonry, 420

timber bridges, 419

Replacing,

long spans, 405

short spans on old substructure, 404

steel bridges, 403, 404

Report,

author to S.P.E.E., 3

home office, 380

progress, 381

Requirements of U. S. Government, 116

Resident engineer,

arbitrary power of, 382

decisions by, 381

instructions to, 380

Resistance of brakes, 315

Restrictions of speed, 412

Retaining walls, 231

Revenue, sources of, 20

Reversal of current, 122

Reversing stresses, 135

effect of, on continuous trusses, 77

Rhett, Albert H., 458

Rhine crossing near Honningen, 471

Ribbed structure versus solid

barrel, 228, 229

Rib depths, economic, 235, 236

Rice, Geo. S., 433

Right-of-way, cost of, 114

Rim-bearing versus center-

bearing swing spans, 287

Rip-rap, 122, 424

Rise,

arch, 226

economic, of suspension

bridge cables, 265, 266

ratio of, to span, 233-235

with span-length unchanged, 225

Rise in price of labor, 348

Risk, assumption of, 340

Rivalry in bridge projects, 20

River traffic, 123

Riveted spans, economics of, 70

Riveted tension members, 199

Riveted versus pin-connected

bridges, 72

Riveting,

arrangement of, 199

machines, 377

sequence of, 214

staggered, 211

Rivets,

loose, 423

spacing, 210

Roads, drainage of, 454

Roadways,

crowning of, 426

widths, 127

widths for military bridges, 473, 474

Rolled I-beam spans, economics

of, 67

Roller-bearing bascules, 290

Rolling-lift bascules, 290

Roof protection for timber bridges, 420

Round corners in plate-girders, 207

Rusting as affecting detailing, 201

S

Sabin, Dr. A. H., 433, 436-438

Safety and permanence in military

bridges, 462

Safety considerations, 370

Safety factor small in military

bridges, 462

Salary for contractor, objectionable,

348, 349

Sand and gravel used without

screening, 390

San Francisco Harbor Bridge,

proposed, 8, 10

Sanitation of bridges and tunnels, 56

Stamping work, 342

Scarcity of timber, growing, 22

Schedule prices for various

sections, 205

Schneider, C. C., 287

Sciotoville bridge, 75, 77

Scour, 122, 424