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300 Core Technical Issues in Reinforcement Steel Engineering (II) 101: How are the dimensions of tension bars in shear walls calculated? Answer: The length of the horizontal section, obtained by subtracting the thickness of the wall minus the thickness of the two protective layers, represents the inner dimension for the tie rod; to this is added two 135-degree bends, each with a length of 10d and greater than 75 mm. 102. What is the typical spacing of tie rods in shear walls? Answer: It shall be twice the spacing of the horizontal or vertical distribution bars in the wall, as specified in the design. 103. When binding shear walls, where is the most difficult part to handle, and how can this problem be solved? Answer: It’s in the corner, where it should be secured firmly and kept vertical. 104. What are the differences in reinforcement for shear walls and pool walls? Answer: For shear wall reinforcement, the vertical bars are on the inside and the horizontal bars on the outside; for pool walls, the positions are reversed. 105. For the horizontal and vertical distribution bars in a pool wall, which one is on the inside and which one on the outside? Answer: The horizontal reinforcement is on the inside of the pool wall, while the vertical reinforcement is on the outside. 106. What other important characteristics are there regarding the reinforcement of swimming pool walls? Answer: Add corbels at the bottom of the pool and at the corners for reinforcement; there are hidden foundation beams at the pool bottom, while there are top beam frames or top ring beams at the pool ceiling. 107. What elements make up a complete steel bar mixing list? Answer: Cover thickness of steel bars, component length, component width, component height, component thickness, width of each support, length of each clear span, clear height of columns, number of components, number of individual reinforcing bars, total number of reinforcing bars, specifications of steel bars, diameter, spacing, anchorage length, hook length, side length, shape and style, angle, correction factor, lap length, number of layers of tie bars, number of longitudinal bars included in inner stirrups, number of clear spans allocated, bending adjustment value, cutting length, completion status, total length, theoretical weight of steel bars, total weight, equivalent tonnage, remarks. 108. In the steel bar scheduling table, what contents are included in the item regarding steel bar arrangement? Answer: The parameters of the rebar, the number of bars, the spacing between them, the dimensions of their shapes, the cutting length, as well as the bending adjustment values. 109. In the steel bar scheduling sheet, what contents are included in the settlement items? Answer: Total length of rebar, theoretical weight, total weight, and composite tonnage. 110. For the 4 column headers of root count, specification, diameter, and spacing, what is the proper way to arrange them? Answer: The number of roots, specifications, diameter, and spacing must be consistent with those indicated in the drawings. 112. In the steel bar specification sheet, is it acceptable to use decimeters or meters as units? Answer: In a broad sense, it can be considered possible; but in a strict sense, it is absolutely not possible, as values need to be converted frequently, which makes it easy for workers to make mistakes. 113. Why is it said that using millimeters as the unit in the steel bar specification sheet is the most standard approach? Answer: The units of measurement used in the rebar scheduling sheet should be consistent with those in the drawings; the drawings are designed using millimeters as the unit of measurement. 114. What is the “reinforcement detailing elevation demonstration method”? Answer: In spreadsheets, it is a method of calculating rebar quantities that involves depicting, arranging, analyzing, and computing rebar in an elevation format. 115. What is the most reasonable basis for calculating the theoretical weight of steel bars? Answer: Based on the specific gravity of iron, using a parametric algorithm is inaccurate. 116. For the classification and summary of steel bar mix designs, what method is the fastest and most accurate? Answer: Use the “Pivot Table” in spreadsheets on a computer, or specialized software. 117. What are the different forms of stair totals? Answer: Beam type, slab type, rotary type, electric type, stepped type, etc. 118. What are the characteristics of a beam-type staircase? Answer: Use the inclined beam as the main support point. 119. What are the characteristics of plate staircases? Answer: The inclined plate is the main component. 120. What are the differences in the design of the enclosure structure for elevators compared to ordinary stairs? Answer: Add sturdy walls as a barrier to prevent harm to people in the surrounding area in the event of an accident. 121. In the flat method, what does the k value mean and what is its purpose? Answer: The k value is a slope coefficient that is used to calculate the slant length of the ladder steps quickly and accurately. 122. How should the inclined length of the tie bars in a straight-flight staircase be determined? Answer: One quarter of the net span of the inclined tread length plus the length extending into the beam multiplied by the k value. 123. In a slab staircase, what is the inherent relationship between the lower main reinforcement and the upper tie reinforcement? Answer: Design it at half the strength of the lower longitudinal reinforcement. 124. In folded-step stairs, why are the rebar bars arranged in an interlocking pattern at the turning corners? Answer: Rebars are interlocked to reinforce weak areas, ensuring that the turning joints remain sturdy. 125. In folded-step stairs, how is the insertion depth of the interlocking rebar at corners calculated? Answer: The diameter of the rebar multiplied by the anchorage length. 126. In slab stairs, where does the thickness of the stair slab refer to, and what symbol is used to denote it? Answer: The vertical distance from the corner of the step to the bottom of the slab. Denote it as h. 127. When calculating which type of rebar, can the thickness of the tread plate be used? Answer: Stair tread support reinforcement. 128. For the inclined longitudinal reinforcement of ladder slats, what value gives the fastest calculation? Answer: Use the k value. 129. What are some good methods and measures to ensure that the tie bars on ladder steps do not get deformed from being stepped on? Answer: Use cross-shaped shims tied under the tie bars. 130. Based on what value is the diagonal length of the stirrups in folded-plate stairs calculated? Answer: The horizontal net span of the step section, as well as the k value. 131. Where are the single-side support points of the ladder step? Answer: On the stair stringer. 132. Why are steel bars added to concrete elements? Answer: Steel bars can compensate for the deficiency in tensile strength of concrete. 133. What is the difference between the tensile and compressive strength of concrete, and by how much? Answer: Its tensile strength is low while its compressive strength is high; the difference is approximately 8 to 10 times. 134. Why are bends made at the ends of grade 1 steel bars, and what is the angle of these bends? Answer: Plain round steel bars cannot be anchored without hooks; therefore, a 180-degree semi-circular hook should be made. 135. In what circumstances is it unnecessary to make hooks for Grade I steel bars? Answer: When under stress alone and as a structural reinforcement. 136. Below the midpoint of a beam’s span, what force acts most significantly on the reinforcing bars? Answer: Tension. 137. At the upper part of the middle support of the beam, which force does the reinforcement experience the most? Answer: Tension. 138. At a distance of 15 centimeters from the support along the net span of the beam, what type of force acts on the rebar with the greatest intensity? Answer: Shear force. 139. On the side of the awning beam or balcony beam, which force does the rebar experience the most? Answer: Torque. 140. At the base of the canopy and balcony slabs, what type of stress does the concrete experience the most? Answer: Tension. 141. What exactly is meant by the term \"lowering the curtain\" regarding awnings, and why does it happen? Answer: The canopy collapsed because the position of the reinforcing bars at the top changed, causing them to be pressed down. 142. What are the common types of stirrups used for positioning rebar? Answer: several-shaped, cross-shaped, I-shaped, horse-shoe shaped, triangular, V-shaped, king-shaped, and so on. 143. What are the advantages and disadvantages of the several-character-shaped horse stool known as “grasshopper legs”? Answer: Simplicity in production is its advantage ； Its disadvantages are its tendency to tip over and its small support area. 144. What are the advantages and disadvantages of cross-shaped shims, and how can they be made using several pieces of material? Answer: Its advantages are a large support area, stability, and the use of material ends; its disadvantage is the large amount of welding required. It is made using 3 to 4 material ends. 145. What are the advantages and disadvantages of the two-tooth hook-type stirrup, and what is its working principle? Answer: Its advantages are simple production and flexibility, while its disadvantage is a small force application area; it utilizes the principle of levers. 146. What are the various reinforcement methods for pre-attached beam frameworks? Which reinforcement method is the best? Answer: 1) Cable-stayed reinforcement type ； 2) Binding reinforcement in loop form (sides, at an angle, wrapped) ； 3) Welded intersections (not allowed) ； 4) Fastening right-angle hook ； 5) Internal spiral fixation type. An internal spiral fixation is the best option. 147. What is the difference between spacing and clear distance? Answer: The spacing is the distance between the center points, while the clear distance is the shortest distance between the edges of the ribs; the two are different. 148. Where is spacing @100 most commonly used? Answer: At the reinforcement stirrup densification area. 149. Where is spacing @50 most commonly used? Answer: Additional stirrups at the intersection of primary and secondary beams. 150. Where is spacing @150 most commonly used? Answer: Wall reinforcement bars, slab reinforcement bars, and wall/column stirrups. 151. Where is spacing @200 most commonly used? Answer: Ordinary stirrups, distribution bars in walls and slabs. 152. Where is spacing @250 most commonly used? Answer: Stirrups for beams and columns that are not required to be seismic-resistant, as well as distribution bars for one-way slabs. 153. How to ensure the accuracy of the spacing between rebar bars when binding them? Answer: Underlining for positioning is the best practice. 154. What is the allowable deviation for the spacing of stirrups? Answer: Plus or minus 20 millimeters. 155. What is the allowable deviation for the spacing of rebar bars? Answer: Plus or minus 10 millimeters. 156. What is the allowable deviation for the spacing of longitudinal reinforcement bars in columns? Answer: Plus or minus 5 millimeters. 157. What are the allowable tolerances for the height and width of the skeleton cross-section? Answer: Plus or minus 5 millimeters. 158. What determines the spacing of the upper layer rebar in a beam? Answer: The 135-degree inclined hook of the stirrups ； Reinforcement bar with a diameter of 25. 159. What is used for positioning the spacing of the rebar at the bottom of the beam? Answer: Use short steel bars with a diameter of 25 mm. Commonly known as shims, iron shims, or reinforcement shims. 160. What is the cutting length of the pitch positioning rib? Answer: Subtract 20mm to 30mm from the beam width. 161. What is the purpose of stirrups? Answer: To bear the concentrated loads generated by the secondary beams in the main beam. 162. How is the inclined length of the suspension bars calculated? Answer: Use the beam height minus the cover thickness multiplied by the slant length coefficient. 163. How is the upper horizontal section of the suspension bar calculated? Answer: The diameter of the stirrup multiplied by 20. 164. How is the lower straight section of the suspension bar calculated? Answer: Add 100mm to the width of the secondary beam. 165. Where should the suspension bars be tied to the beam? Answer: The center point below the hanging bar is directly above the center point of the lower surface of the secondary beam, and it is located inside the angle bars of the main beam. 166. Is it correct to attach the tie bars to the stirrups and bind them together? Why? Answer: No, because it affects the load-bearing performance. 167. What are the various angles of the inclination of stirrups, and under what circumstances are they used? Answer: There are two angles, 45 degrees and 60 degrees, which are applied when the beam height is greater than, equal to, or less than 800. 168. How many categories are there for lumbar muscles? Answer: There are two types: constriction lumbar muscles and torsion-resistant lumbar muscles. 169. How should the waist tendons be arranged in a beam? Answer: They are arranged at equal intervals within the range of the beam clear height minus the cover thickness. 170. What is the difference between anti-torsion lumbar muscles and structural lumbar muscles? Answer: Different codes are used for different functions; those for anti-torsion lumbar muscles start with N, while those for structural lumbar muscles start with G. The anti-torsion waist reinforcement is anchored in the same manner as the beam longitudinal reinforcement, with a construction waist reinforcement anchor length of 15d. 171. To which category do the waist bars that are anchored in the same way as the longitudinal beams belong? Answer: It belongs to the anti-torsion lumbar muscles. 172. To which category does the lumbar tendon that is anchored for 15 days belong? Answer: It belongs to the structural lumbar muscles. 173. What is the specified maximum vertical spacing for the lumbar muscles? Answer: Not more than 200mm. 174. At what height must stirrups be added to a beam? Answer: When the web height is ≥ 450 mm. 175. For diaphragm beams and hidden beams with straight anchors at both ends, how is the beam length determined? Answer: The length of the beam is determined by the net span plus twice the anchorage length. 176. For continuous beams and hidden beams with a straight anchor at one end, how is the beam length determined? Answer: The width of one end support plus the net span plus the anchorage length. 178. What is the concept of a beam? Answer: A supporting beam member with at least 1 bearing, such as the beam strut inside **. 179. What is the concept of a column? Answer: A component that is erected perpendicular to the ground and has a certain foundation. 180. What is the concept of a wall? Answer: A plate-like component built perpendicular to the ground. 181. What are the differences between shear walls and brick walls? Answer: Brick walls may have holes, while shear walls contain hidden beams and columns that provide diagonal support; there are at least 5 differences. 182. What is the concept of a floor slab? Answer: In buildings, the partitions, floors, and ceilings between different floors. 183. What is the concept of a roof panel? Answer: The roof of a house is its ceiling. 184. What are the differences in the reinforcement design between floor beams and roof beams? Answer: The rebar in floor beams can be anchored directly, while the rebar in roof beams cannot be anchored directly; in addition, an increased anchorage length is required. 185. What are the differences in reinforcement between hidden beams and edge beams in wall beams? Answer: The rebar in hidden beams can be anchored directly, while the rebar in edge beams cannot be anchored directly; in addition, an increased anchorage length is required. 186. What are the differences and similarities in the reinforcement of wall columns and frame columns? Answer: The lap length for the longitudinal bars in wall columns is the same as that in shear walls, while the lap length for the longitudinal bars in frame columns is determined using a correction factor based on the area percentage. When reinforcing with stirrups, the construction requirements for wall columns and frame columns are the same. 187. Can the reinforcement configuration of tie beams in wall beams be applied interchangeably with that of ring beams in brick walls? Answer: No, the requirements for anchorage length are different. 188. What are the similarities between the reinforcement in lintels and that in ring beams? Answer: The reinforcement in a lintel is generally similar to that in a ring beam cross-section, with relatively less reinforcement on the lintel. 189. What is a simply supported beam, what is a connecting beam, and what is a cantilever beam? Answer: A beam with only two supports is called a simply supported beam ； A beam with three or more supports that are connected to each other is called a connecting beam ； A beam that has only one support and is suspended at one end is called a cantilever beam. 190. How are the cross-sectional heights at the root and tip of a cantilever beam represented in the flat method? Answer: It is represented using a slash /. 191. What is the length of the hook at the tip of the top reinforcement bar in a cantilever beam? Answer: 12 times the diameter of the rebar. 192. What is the anchorage length of the lower reinforcement in a cantilever beam at its root? Answer: 12 times the diameter of the rebar; for smooth rebar, 15 times the diameter. 193. What is the length of the upper two rows of reinforcement in the cantilever beam within the cantilevered area? Answer: 0.75 times the net length of the cantilevered section. 194. Under what circumstances must the middle rebar at the top of a cantilever beam be bent downward? Answer: When the ratio of the net length of the cantilevered section to the height at the root of the cantilever beam is greater than one-quarter. 195. Where is the maximum shear force in a cantilever beam? Answer: At the root of the beam. 196. In the flat method, what component does KZ represent? Answer: Frame column. 197. In the flat method, what component does Q represent? Answer: The shear wall body. 198. In the flat method, what component does YAZ represent? Answer: Restrict edge dark columns. 199. In the flat method, what component does LL represent? Answer: Diagonal bracing. 200. In the flat method, what component does YDZ represent? Answer: Constrain the edge end posts.