SECTION 10.1 GENERAL 10.1.1 SCOPE This part of the Manual covers the structural design and installation of reinforced concrete pipe for railway culverts. Pipe geometry may be circular, arch, or elliptical. 10.1.2 DEFINITIONS 10.1.2.1 Pipe Installation Conditions a. Trench Installation. The pipe is installed in a relatively narrow trench excavated in undisturbed soil and then covered with backfill extending to the ground surface. b. Positive Projecting Embankment Installation. The pipe is installed on original ground or compacted fill with the top of the pipe above the ground, or compacted fill and then covered with embankment. c. Negative Projecting Embankment Installation. The pipe is installed within a relatively narrow trench with the top of the pipe below the natural ground or compacted fill, and then covered with embankment. d. Induced Trench Installation. The pipe is installed in a trench, backfilled with compressible material over the pipe, and then covered by a high embankment. e. Jacked or Tunneled Installation. The pipe is installed without removal of the ground above the pipe. Grouting of the exterior annular space around the pipe may be required to ensure full contact with the soil around the pipe. If existing soil conditions require an oversized tunnel, or if anticipated service conditions require access to the pipeline, a carrier pipe may be installed within the tunnel or casing pipe. 10.1.2.2 Direct Bury Pipe Installation Types Concrete Pipe may be installed in accordance with the requirements for a Type 1 through Type 4 Installation as shown in Figure 8-10- 1, and defined in Tables 8-10- 1, and 8-10- 2. The default installation for design shall be a Type 2 Installation, unless otherwise designated by the Engineer.
Figure 8-10- 1 Standard Trench/Embankment Installation (Circular Pipe shown; also applies to arch and elliptical pipe)
Table 8-10- 1 Standard Installations Soil and Minimum Compaction Requirements (Note: Compaction is a percentage of ASTM D698)
Table 8-10- 2 Equivalent USCS and AASHTO Soil Classifications for Soil Designations
10.1.2.3 Symbols B c = Outside width of the pipe (ft) B d = Width of the pipe trench (ft) B f = Bedding factor, defined as the ratio between the supporting strength of buried pipe to the strength of the pipe determined in the three- edge bearing test obtained according to requirements of ASTM Designation C497. B fe = Bedding factor for earth loads; the ratio of maximum moment in the three- edge bearing test to the maximum moment in the buried condition when the vertical soil load and three- edge bearing load are equal. B fll = Bedding factor for live loads; the ratio of maximum moment in the three- edge bearing test to the maximum moment in the buried condition when the vertical live load and the three- edge bearing load are equal. Coeff d = Coefficient of live load distribution through the pipe. D = inside diameter (or horizontal width) of the pipe (in) D o = outside diameter (or horizontal width) of the pipe (in) D- Load = the supporting strength of a pipe loaded under three- edge bearing test conditions, expressed in pounds per linear foot, per foot of inside diameter or horizontal span. (lbs/ft/ft) D 0.01 = the maximum three- edge bearing test load supported by a concrete pipe before a crack having a width of 0.01 inch occurs throughout a continuous length of 1 foot. (lbs/ft/ft) D ult = the maximum three- edge bearing test load supported by a concrete pipe Dist = Distribution of live load through the pipe (ft) FS = Factor of Safety; normally taken as 1.0 for the D 0.01 inch service D- load. H = Height of cover over the top of the pipe (ft) taken from the base of rail to the top of the pipe (ft.) I = the impact load applied to the top of the pipe as a fraction of the live load. L T = Length of tie (ft) IM = impact load factor
P = Train Axle Load (lbs) = 80,000 lbs for Cooper E- 80 Loading S = axle spacing (ft.) = 5 ft. between 80 kip axles S i = inside span of pipe (in) w = unit weight of the backfill material (lbs per cubic foot) W E = earth loads transmitted to the pipe (lbs per linear foot) W F = weight of fluid carried in the pipe (lbs per linear foot) W l = live load at the top of the pipe (lbs per square foot) W L = live load including impact transmitted through the pipe (lbs per linear foot) W S = other loads transmitted to the pipe (lbs per linear foot) 10.2.1 PIPE SECTION 10.2 MATERIALS Pipe shall conform to the following ASTM Standards for type, size, shape, manufacturing, testing and strength requirements as specified by the Engineer. a. ASTM Designation C76, Specification for Reinforced Concrete Culvert, Storm Drain, and Sewer Pipe. b. ASTM Designation C506, Specification for Reinforced Concrete Arch Culvert, Storm Drain, and Sewer Pipe. c. ASTM Designation C507, Specification for Reinforced Concrete Elliptical Culvert, Storm Drain, and Sewer Pipe. d. ASTM Designation C655, Specification for Reinforced Concrete D- Load Culvert, Storm Drain, and Sewer Pipe 10.2.2 RUBBER GASKETS Rubber gaskets, if specified, shall conform to ASTM Designation C443, Specification for Joints for Concrete Pipe and Manholes, Using Rubber Gaskets. 10.2.3 ACID RESISTANT COATINGS OR LINERS Acid resistant coatings or liners shall be specified by the Engineer for the particular condition required.
SECTION 10.3 DESIGN 10.3.1 GENERAL The design of reinforced concrete pipe culverts must take into account the type of installation and bedding, the soil constants of the natural ground and backfill, the relative settlements of the pipe, pipe foundation, bedding, backfill and natural ground, acidity of the flow, the physical measurements such as depth of cover and width of cut, determination of earth load, live load, impact, and any additional loading. 10.3.2 REFERENCES Satisfactory design methods, utilizing more exact design procedures, are referenced for the use of the Engineer. a. American Concrete Pipe Association Concrete Pipe Design Manual b. American Concrete Pipe Association Concrete Pipe Handbook c. ASCE 15-98, Standard Practice for the Direct Design of Buried Precast Reinforced Concrete Pipe Using Standard Installations (SIDD) 10.3.3 LOADS a. Design loading on the pipe shall include Dead (Earth) Load, Live (Railroad) Load, Impact, and any other surcharge loads. Unless otherwise specified by the Engineer, Live (Railroad) Load shall be Cooper E 80. Earth Loads and Cooper E 80 Live Loads may be obtained from Figure 8-10- 2.
Figure 8-10- 2 Loads on Concrete Pipe b. The Engineer may use the equation below to determine the earth load transmitted to the pipe. Other acceptable methods of analyses are given in Article 10.3.2 W E = 1.45 x B c x H x w EQ. 10-1 c. Track loading to be supported by the pipe is shown in Figure 8-10- 2. The indicated loading includes a variable Impact Load of 40% at 1.5 feet below the base of rail, and 0% at 10 feet. The equation for this is shown below: IIII = 1.. 0.40 EQ. 10-2 d. The Engineer may calculate the E 80 live load on the pipe in (psf) by dividing the 80 kip axle load by the 5 foot spacing length between axles, and a total width of 8 feet for the track
plus the load distribution through the height of cover using a ratio of 1:1 as shown in Figure 8-10- 3: Figure 8-10- 3 Live Load Distribution Through the Soil e. The following equation may be used to calculate the live load at the top of the pipe in pounds per square foot: WW = EQ. 10-3 f. Where the live load spread from multiple tracks running side by side overlap (center- to- center spacing of tracks is less than L T + H), the live load distribution shall consider the area that encompasses the spread from all interacting tracks. That load shall be assumed uniform over the entire area of the live load spread.
g. When the live load reaches the top of the pipe, it is further dissipated through the structure of the pipe a distance of: Coeff d = 242 D o - 1.97 + 0.855 Dist = Coeff d x D o < 54 inches EQ. 10-4 EQ. 10-5 h. Live load pressure at the top of the pipe is independent of the direction the train travels with respect to the axis of the pipe. i. For track running perpendicular to the longitudinal axis of the pipe, the live load in pounds per linear foot for design shall be: WW = EQ. 10-6 For track running parallel to the longitudinal axis of the pipe, the live load in pounds per linear foot for design shall be: WW = WW BB EQ. 10-7 j. Any surface surcharges, other than track load shall be converted to additional height of fill to determine their loading on the pipe. k. Loading on a carrier pipe, that is within a casing pipe, shall be taken as the full Dead + Live + Impact Load without consideration of the presence of the casing, unless the casing is permanently protected from corrosion using such means as providing extra pipe thickness or a resistant coating. l. If a trench design is utilized, the design trench width shall be indicated on the construction drawings as a maximum width of trench. The minimum width of trench shall be B c +2 feet, or 1.33 B c, whichever is greater.
10.3.4 BEDDING FACTORS a. Earth load bedding factors to be used in the equation for determination of the D- Load shall be obtained from Table 8-10- 3 or as permitted by interpolation. Pipe Installation Methods Standard Installation Types (Note 1) 1 2 3 4 Tunnel Direct Bury (Note 2) D = 12 inches 4.4 3.2 2.5 1.7 D = 24 inches 4.2 3.0 2.4 1.7 D = 36 inches 4.0 2.9 2.3 1.7 D = 72 inches 3.8 2.8 2.2 1.7 D = 144 inches 3.6 2.8 2.2 1.7 Jacked or Tunneled (all 3.0 sizes) Carrier Pipe (all sizes) 3.6 2.8 2.2 1.7 Casing Pipe (all sizes) 3.0 Note 1: See Figure 8-10- 1 and Tables 8-10- 1 and 8-10- 2 Note 2: For pipe diameters other than listed in Table 8-10- 3, earth load bedding factors can be obtained by interpolation Table 8-10- 3 Earth Load Bedding Factors
b. Live load bedding factors to be used in the equation for determination of the D- Load shall be obtained from Table 8-10- 4, or as permitted by interpolation. Fill Height (ft) Pipe Diameter, inches 12 24 36 48 60 72 84 96 108 120 144 1.0 2.2 2.2 1.7 1.5 1.4 1.3 1.3 1.3 1.1 1.1 1.1 1.5 2.2 2.2 2.1 1.8 1.5 1.4 1.4 1.3 1.3 1.3 1.1 2.0 2.2 2.2 2.2 2.0 1.8 1.5 1.5 1.4 1.4 1.3 1.3 2.5 2.2 2.2 2.2 2.2 2.0 1.8 1.7 1.5 1.4 1.4 1.3 3.0 2.2 2.2 2.2 2.2 2.2 2.2 1.8 1.7 1.5 1.5 1.4 3.5 2.2 2.2 2.2 2.2 2.2 2.2 1.9 1.8 1.7 1.5 1.4 4.0 2.2 2.2 2.2 2.2 2.2 2.2 2.1 1.9 1.8 1.7 1.5 4.5 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.0 1.9 1.8 1.7 5.0 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.0 1.9 1.8 5.5 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.0 1.9 6.0 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.1 2.0 6.5 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.2 Note 1: For pipe diameters other than listed in Table 8-10- 4, B fll values can be obtained by interpolation Note 2: For fill heights equal to or greater than 6.5 feet, the live load bedding factor shall be 2.2 10.3.5 MINIMUM PIPE STRENGTH Table 8-10- 4 Live Load Bedding Factors Pipe subjected to track loads shall have a minimum strength of D 0.01 = 1350 lbs/ft/ft (Class III) even if analysis indicates that a lower D- Load is satisfactory. 10.3.6 FACTOR OF SAFETY The standard Factor of Safety of 1.0 against a 0.01 inch crack D- Load should be used for design unless the Engineer indicates that a higher factor of safety is required. 10.3.7 PIPE STRENGTH The required D- Load of the pipe shall be determined by the following equation: D. = + EQ. 10-8
10.3.8 ALTERNATE DESIGN PROCEDURE In lieu of carrying out the complete design analysis required by these guidelines, the Engineer may choose the required pipe strength for E 80 loading based on Table 8-10- 5. Class III = Class IV = Class V = 1350 lbs/ft/ft 2000 lbs/ft/ft 3000 lbs/ft/ft Type 2 Installation_ Inside Diameter, Di (inches) Fill Height (ft) From Base of Rail to Top of Pipe 1 1.5 2 3 4 5 6 7 8 9 10 12 1386 1371 1342 1297 1270 1257 1255 1262 1277 1298 1326 15 1507 1319 1291 1251 1226 1215 1215 1223 1239 1261 1288 18 1290 1279 1254 1217 1196 1187 1189 1199 1216 1239 1267 24 1227 1220 1199 1170 1156 1152 1158 1172 1193 1219 1250 30 1313 1197 1157 1135 1125 1126 1136 1153 1175 1205 1236 36 1434 1183 1123 1107 1103 1108 1121 1141 1167 1197 1232 42 1463 1223 1135 1082 1082 1091 1107 1129 1156 1188 1224 48 1515 1283 1160 1067 1070 1081 1099 1123 1152 1185 1222 54 1562 1384 1212 1071 1074 1086 1104 1128 1157 1190 1227 60 1614 1506 1271 1076 1080 1092 1110 1135 1164 1197 1235 66 1670 1555 1369 1138 1087 1099 1118 1142 1172 1206 1243 72 1732 1607 1487 1209 1094 1107 1126 1151 1181 1215 1253 78 1735 1611 1491 1238 1116 1112 1131 1156 1186 1221 1258 84 1740 1616 1496 1269 1138 1118 1138 1162 1192 1226 1264 90 1745 1673 1544 1301 1181 1125 1144 1169 1199 1233 1270 96 1750 1733 1595 1336 1227 1132 1151 1176 1205 1239 1277 102 1884 1739 1601 1403 1255 1168 1158 1182 1212 1246 1283 108 2041 1745 1607 1478 1284 1207 1165 1190 1219 1253 1290 114 2047 1752 1662 1485 1315 1232 1185 1197 1226 1260 1297 120 2053 1758 1721 1492 1347 1257 1206 1204 1234 1267 1305 126 2060 1824 1728 1518 1381 1274 1221 1212 1241 1275 1312 132 2067 1895 1735 1544 1416 1292 1236 1219 1249 1283 1320 138 2073 1971 1742 1572 1454 1309 1251 1227 1257 1290 1327 144 2081 2053 1750 1600 1493 1327 1266 1235 1264 1298 1335 Table 8-10- 5 Reinforced Concrete Pipe Fill Height Tables for E 80 Loading
Inside Diameter, inches Type 2 Installation Fill Height (ft) 11 12 13 14 15 16 17 18 19 20 12 1381 1438 1497 1558 1621 1684 1749 1815 1882 1949 15 1343 1399 1457 1517 1578 1640 1704 1768 1833 1899 18 1321 1378 1435 1495 1556 1618 1681 1744 1809 1875 24 1305 1362 1421 1481 1542 1605 1668 1733 1798 1864 30 1292 1350 1409 1470 1532 1594 1658 1722 1788 1853 36 1289 1348 1408 1470 1532 1595 1660 1725 1791 1857 42 1282 1341 1401 1463 1526 1589 1654 1719 1784 1851 48 1280 1339 1400 1462 1525 1589 1653 1718 1784 1851 54 1286 1345 1406 1468 1531 1595 1659 1724 1790 1857 60 1293 1353 1414 1476 1539 1603 1667 1733 1799 1865 66 1302 1362 1423 1485 1549 1613 1677 1743 1809 1876 72 1312 1372 1433 1496 1559 1624 1689 1754 1821 1887 78 1317 1377 1438 1500 1564 1628 1692 1758 1824 1891 84 1323 1382 1443 1505 1568 1632 1697 1762 1828 1895 90 1328 1388 1449 1511 1574 1638 1702 1767 1833 1899 96 1335 1394 1455 1517 1580 1643 1708 1773 1838 1905 102 1341 1401 1462 1523 1586 1649 1714 1779 1844 1910 108 1348 1408 1468 1530 1592 1656 1720 1785 1850 1916 114 1355 1415 1475 1537 1599 1662 1726 1791 1857 1922 120 1363 1422 1482 1544 1606 1669 1733 1798 1863 1929 126 1370 1429 1489 1551 1613 1676 1740 1805 1870 1936 132 1377 1437 1497 1558 1620 1683 1747 1812 1877 1943 138 1385 1444 1504 1566 1628 1691 1756 1819 1884 1950 144 1393 1452 1512 1573 1635 1698 1762 1826 1891 1957 Table 8-10- 5 Reinforced Concrete Pipe Fill Height Tables for E 80 Loading (Cont.) Notes: Values in the Table are D- Load values for the D 0.01, D- Load strengths of the pipe in lbs/ft/ft. The assumptions used to determine the values in the table are: o W = 120 pcf unit weight of soil o Live Load = E 80 o Installation Type = Type 2 Installation using a granular soil compacted to 90% Standard Proctor o Installation Condition = positive projecting embankment condition
10.4.1 PREPARATION OF SUBGRADE 10.4.1.1 Excavation SECTION 10.4 INSTALLATION a. Trenches shall be excavated in accordance with bank stability requirements to a width sufficient to allow for proper joining of the pipe and thorough compaction of the bedding and backfill material under and around the pipe. The completed trench bottom shall be firm and cleaned for its full length and width. b. The pipe trench bottom shall be cambered longitudinally if settlement after installation is expected. If camber of the pipe trench is required, the indicated camber must be shown on the plans. c. Where specified on the plans, the excavation for a pipe to be placed within embankment fill shall be made after the embankment has been completed to the specified height above the top of the pipe. 10.4.1.2 Foundation a. If the foundation is incapable of supporting the pipe loads, an adequate support shall be specified or approved by the Engineer. 10.4.2 PIPE INSTALLATION 10.4.2.1 Laying Pipe a. Pipe laying shall begin at the downstream end of the culvert. The bell or groove end of the pipe shall be placed upstream. No culvert shall be put into service until a suitable outlet is provided for the water. b. Elliptical pipe shall be placed with the vertical axis within 5 degrees of a vertical plane through the longitudinal axis of the culvert. 10.4.2.2 Bedding a. Pipe bedding and placement shall be specified to conform to one of the Installations denoted in Table 8-10- 1. b. When pipe cannot be placed on a prepared surface, but must instead be placed on an unprepared surface, the installation shall be considered to be a Type 4 Installation. Type 4 Installations should only be used for emergency work, and are not recommended for
permanent installations unless authorized by the Engineer. For typical Type 4 Installations, see Figure 8-10- 1, and Table 8-10- 1. 10.4.2.3 Joining Pipe a. Pipe may either be bell and spigot or tongue and groove design unless otherwise specified. When bell pipe is used, a shallow excavation shall be made underneath the bell of sufficient depth so that the bell does not rest on the bedding material. b. Pipe sections shall be joined so that the ends are fully entered and the inner surface areas are flush and even per pipe manufacturer s recommendations. c. Joints shall be made with grout, rubber gaskets, plastic mastic compounds, or other combination of these types as approved and specified by the Engineer. Mortar joints in pipe that is jacked into place shall not be sealed with mortar until the culvert jacking is complete. d. In areas where pipe sections could separate, suitable ties should be specified to prevent pipe section separation. e. Endwalls or headwalls may be used for culverts under tracks and designed to resist pipe separations as well as to retain the embankment. 10.4.2.4 Leak Resistance If leak resistant joints are required, rubber gasketed pipe is recommended. When such joints are specified, the pipe should be tested for infiltration and exfiltration as specified by the Engineer. The maximum rate of leakage shall conform to the following accepted requirements, or to other standards set forth by the Engineer. Infiltration 0.6 gallons per hour per inch of diameter per 100 feet of pipe Exfiltration 0.6 gallons per hour per inch of diameter per 100 feet of pipe when subjected to an internal head of 2 feet, and increased by 10% for each additional 2 feet of head. 10.4.2.5 Culverts Carrying High Acid Fluids Where the ph of the conducted fluid is less than 4.5, the internal surfaces of the culvert shall be protected from acid attack by a suitable permanent coating or liner. The Engineer shall specify the type of protection and the means of application.
10.4.3 BACKFILL AND EMBANKMENT 10.4.3.1 General a. The backfill around the culvert shall be placed in accordance with the installation requirements denoted in Table 8-10- 1 and Figure 8-10- 1, and other requirements of Section 8, Part 10. b. All culverts that are to carry track load shall have the backfill thoroughly compacted to a minimum density of 95% as determined by ASTM D698, and as specified elsewhere in the project specifications for adjacent embankment. 10.4.3.2 Embankment Bedding a. Where rock or noncompressible foundation material is encountered, the hard unyielding material should be excavated below the elevation of the bottom of the pipe or pipe bell to a depth in accordance with Table 8-10- 1, or ½ inch for each foot of fill over the top of the pipe, whichever is greater, but need not be more than ¾ of the diameter (or horizontal span) of the pipe. b. For a negative projecting embankment condition, the width of the excavation, B d, shall be at least 1.33 B c and with a minimum of 2 feet greater than the outside diameter of the pipe for thorough filling and compaction of the void space under the pipe haunch. 10.4.3.3 Trench Bedding a. Materials for backfill on each side of the pipe for the full width of the trench and to an elevation of 1 foot above the pipe shall not contain frozen lumps, stones that would be retained on a 2 inch sieve, chunks, highly plastic clay, or other objectionable material. Granular backfill material shall have 100% passing a ¾ inch sieve, not less than 95% passing a ½ inch sieve, and not less than 95% retained on a No. 16 sieve. Oversized material shall be removed at the source of the material, except as directed by the Engineer. b. When the top of the pipe is even with or below the top of the trench, backfill material shall be placed at or near the optimum moisture content and compacted in layers not exceeding 6 inches (compacted) on both sides of the pipe for the full required length. c. Backfill material shall be placed and compacted for the full depth of the trench, unless induced trench installation is used.
d. When the top of the pipe is above the top of the trench, backfill shall be placed at or near optimum moisture content and compacted in layers not exceeding 6 inches (compacted) and shall be brought up evenly on both sides of the pipe for its full length to an elevation 1 foot above the top of the pipe. The width of backfill on each side of the pipe for the portion above the top of the trench shall be equal to twice the diameter of the pipe or 12 feet, whichever is less. The backfill material used in the trench section and the portion above the top of the trench for a distance on each side of the pipe equal to the horizontal diameter and to 1 foot above the top of the pipe shall conform to the requirements for backfill in paragraph a. The remainder of the backfill shall meet the requirements for embankment construction. e. The width of the trench B d, shall be 1.33 B c, but not less than 2 feet greater than the outside diameter of the pipe in order to completely fill the void. 10.4.3.4 Induced Trench Method (Special Design) a. The Induced Trench method shall not be used when the pipe is subjected to track loading without making a complete investigation of settlements involved. b. When the Induced Trench method is used, design and installation requirements shall follow the recommendations set forth in the references in Article 10.3.2. The embankment shall be completed as required in Article 10.4.3.3 to a height above the pipe equal to the vertical outside diameter of the pipe plus 1 foot. A trench equal in width to the outside horizontal diameter of the pipe, in depth equal to the vertical outside diameter of the pipe, and to the length shown on the plans shall then be excavated to within 1 foot of the top of the pipe, trench walls being as nearly vertical as possible. This trench shall be loosely filled with highly compressible material. Construction of the embankment above the pipe shall then proceed in a normal manner using regular fill material. c. The length of the Induced Trench method shall be determined by the Engineer in keeping with the design assumptions and the pipe strength being used. d. When the Alternate Induced Trench method is used, the embankment shall be constructed in a normal manner to a height above the culvert bedding elevation equal to twice the outside diameter of the pipe. A trench as required shall then be excavated with the walls as nearly vertical as possible, and the pipe bedded and backfilled to 1 foot above the pipe as called for in Article 10.4.3.3. The remaining portion of the trench shall then be loosely filled with highly compressible material. Construction of embankment shall then proceed in a normal manner. e. In no case shall the length of compressible material extend to the ends of the culvert.
f. Rock fill shall not be dumped over the culvert without a sufficient cushion of earth to prevent breakage of the pipe. 10.4.3.5 Jacking Pipe a. Pipe used for jacking shall form a continuous smooth outside surface when placed in contact with the adjacent pipe. The tongue or spigot shall preferably be at the downstream end. Jacking frames shall be so constructed as to avoid breaking the pipe or forcing it out of alignment. The pipe shall preferably be jacked upgrade in order to provide drainage at the heading during excavation. Satisfactory means shall be provided for maintaining the lead pipe at the correct line and grade. b. The pipe shall be installed according to plans and specifications. The contractor s submittal shall document the construction procedure, extra pipe reinforcement, jack shield (if required), jacking pit location, shoring, estimated deformation, track monitoring procedures, and other features for the safe and satisfactory completion of the work. Plans prepared by the contractor giving the construction details shall be submitted to the Engineer for review. c. Voids created during jacking operations shall be filled with a suitable grout material. Grout shall be pumped through grout ports integrally cast into the pipe, or drilled after production. Locations shall be recorded after mining is completed. d. Monitor elevation and alignment of the railroad track above during the jacking procedures. Jacking must be stopped and any problems corrected if track movement is detected. 10.4.3.6 Installing Pipe in Tunnels When it is necessary to place culvert pipe by tunneling, plans and specifications for the completed structure shall be prepared by the Engineer. The contractor shall set forth the construction procedures and other necessary details and submit them to the Engineer for review.