[Engineering Version] Daily Question 20180406
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The construction area of a comprehensive building in a certain city is 1,450㎡. It is a building with 4 floors on the left side and 2 floors on the right side; its structural system is brick-concrete. During construction, a concrete mixing plant was set up at the site, and small components were prefabricated on-site. When checking the quality of these prefabricated components at the construction site, 600 samples were inspected, and the following quality issues were found:Issues:
(1) What statistical method should the construction unit use to analyze these quality issues?
(2) What are the main quality problems associated with the prefabricated components? What measures can be taken to address them?
Answer: (1) Given the characteristics of this situation, the construction unit should use the Pareto chart method for analysis. (2) Main quality issues: 1) Pareto chart. 2) Analysis: Through Pareto analysis, the main quality issues are honeycombing and pitting on the surface of prefabricated components, as well as local reinforcement exposure. ①The rough areas should be washed with clean water; once thoroughly moistened, they should be smoothed out using cement slurry or 1:2 cement mortar. ②Clean the concrete and rust from the exposed rebar, then smooth it out by applying 1:2 cement mortar. If the exposed reinforcement is deep, the weak concrete should be removed and cleaned thoroughly; then it should be compacted with concrete of a higher grade containing aggregate, followed by proper curing. ③The small cells can be first rinsed thoroughly with water, and then repaired using 1:2 cement mortar ； For large honeycombs, loose stones and protruding particles must first be removed and the structure shaped into a trumpet shape; it should then be rinsed thoroughly with clean water, compacted using concrete of a higher grade, and given proper curing.
(1) Given the characteristics of this problem, the construction unit should choose the Pareto chart method for analysis. (2) Main quality issues: 1) Pareto chart preparation; 2) Analysis: Through Pareto analysis, the main quality issues are honeycombing and pitting on the surface of precast components, as well as localized reinforcement exposure. ①The rough areas should be washed with clean water; once thoroughly moistened, they should be smoothed out using cement slurry or 1:2 cement mortar. ②Remove the concrete and rust from the exposed rebar
(1) Use the Pareto chart method. (2) Main quality issues: honeycombing and pitting on the surface of prefabricated components, as well as localized missing rebar. Treatment method: 1. Scrub the rough surface with clean water; once it is thoroughly wet, smooth it out using cement slurry or 1:2 cement mortar. 2. Clean the concrete and rust from the exposed rebar, then smooth it out by applying 1:2 cement mortar. If the exposed reinforcement is deep, remove the weak concrete, clean the area thoroughly, compact it with concrete of a higher grade containing aggregate, and provide proper curing. 3. Small honeycombs can be first rinsed thoroughly with water, and then repaired using 1:2 cement mortar ； For large honeycombs, loose stones and protruding particles must first be removed and the structure shaped into a trumpet shape; it should then be rinsed thoroughly with clean water, compacted using concrete of a higher grade, and given proper curing.
、(1) Given the characteristics of this problem, the construction unit should use the Pareto chart method for analysis. (2) Main quality issues: Pareto chart analysis: Through pareto chart analysis, the main quality issues are honeycombing and pitting on the surface of precast components, as well as localized missing rebar. What treatment methods can be adopted: ① Wash the rough areas with clean water; once they are thoroughly moistened, smooth them out using cement slurry or 1:2 cement mortar. ②Clean the concrete and rust from the exposed rebar, then smooth it out by applying 1:2 cement mortar. If the exposed reinforcement is deep, the weak concrete should be removed and cleaned thoroughly; then it should be compacted with concrete of a higher grade containing aggregate, followed by proper curing. ③The small cells can be first rinsed thoroughly with water, and then repaired using 1:2 cement mortar ； For large honeycombs, loose stones and protruding particles must first be removed and the structure shaped into a trumpet shape; it should then be rinsed thoroughly with clean water, compacted using concrete of a higher grade, and given proper curing.
(1) Given the characteristics of this problem, the construction unit should choose the Pareto chart method for analysis. (2) Main quality issues: 1) Pareto chart preparation; 2) Analysis: Through Pareto analysis, the main quality issues are honeycombing and pitting on the surface of precast components, as well as localized reinforcement exposure. ①The rough areas should be washed with clean water; once thoroughly moistened, they should be smoothed out using cement slurry or 1:2 cement mortar. ②Remove the concrete and rust from the exposed rebar...
(1) What statistical method should the construction unit use to analyze the existing quality issues? The construction unit should choose the Pareto chart method for analysis. (2) What are the main quality issues with precast components? What treatment methods can be employed? Through Pareto chart analysis, the main quality issues are honeycombing and pitting on the surface of the precast components, as well as local missing rebar. a) Wash the pitted areas with clean water; once thoroughly moistened, smooth them out using cement slurry or 1:2 cement mortar. b) Clean the concrete and rust from the exposed rebar, then smooth it out by applying 1:2 cement mortar. If the exposed reinforcement is deep, the weak concrete should be removed and cleaned thoroughly; then it should be compacted with concrete of a higher grade containing aggregate, followed by proper curing. c) The small cells can be first rinsed thoroughly with water, and then repaired using 1:2 cement mortar ； For large honeycombs, loose stones and protruding particles must first be removed and the structure shaped into a trumpet shape; it should then be rinsed thoroughly with clean water, compacted using concrete of a higher grade, and given proper curing.
(1) The construction unit should choose the Pareto chart method for analysis. (2) Main quality issues: 1) Pareto chart; 3) Analysis: Through Pareto analysis, the main quality issues are honeycombing and pitting on the surface of precast components, as well as localized reinforcement exposure. ①The rough areas should be washed with clean water; once thoroughly moistened, they should be smoothed out using cement slurry or 1:2 cement mortar. ②Clean the concrete and rust from the exposed rebar, then smooth it out by applying 1:2 cement mortar. If the exposed reinforcement is deep, the weak concrete should be removed and cleaned thoroughly; then it should be compacted with concrete of a higher grade containing aggregate, followed by proper curing. ③The small cells can be first rinsed thoroughly with water, and then repaired using 1:2 cement mortar ； For large honeycombs, loose stones and protruding particles must first be removed and the structure shaped into a trumpet shape; it should then be rinsed thoroughly with clean water, compacted using concrete of a higher grade, and given proper curing.
Answer: (1) Use the Pareto chart method. (2) Major quality issues: honeycombing and pitting on the surface of precast components, as well as localized exposure of rebar. Treatment method: 1. Scrub the rough surface with clean water; once it is thoroughly wet, smooth it out using cement slurry or 1:2 cement mortar. 2. Clean the concrete and rust from the exposed rebar, then smooth it out by applying 1:2 cement mortar. If the exposed reinforcement is deep, remove the weak concrete, clean the area thoroughly, compact it with concrete of a higher grade containing aggregate, and provide proper curing. 3. Small honeycombs can be first rinsed thoroughly with water, and then repaired using 1:2 cement mortar ； For large honeycombs, loose stones and protruding particles must first be removed and the structure shaped into a trumpet shape; it should then be rinsed thoroughly with clean water, compacted using concrete of a higher grade, and given proper curing.
Answer: (1) Given the characteristics of this problem, the construction unit should choose the Pareto chart method for analysis. (2) Main quality issues: 1) Pareto chart. 2) Analysis: Through Pareto analysis, the main quality issues are honeycombing and pitting on the surface of prefabricated components, as well as local reinforcement exposure. ①The rough areas should be washed with clean water; once thoroughly moistened, they should be smoothed out using cement slurry or 1:2 cement mortar. ②Clean the concrete and rust from the exposed rebar, then smooth it out by applying 1:2 cement mortar. If the exposed reinforcement is deep, the weak concrete should be removed and cleaned thoroughly; then it should be compacted with concrete of a higher grade containing aggregate, followed by proper curing. ③The small cells can be first rinsed thoroughly with water, and then repaired using 1:2 cement mortar ； For large honeycombs, loose stones and protruding particles must first be removed and the structure shaped into a trumpet shape; it should then be rinsed thoroughly with clean water, compacted using concrete of a higher grade, and given proper curing.
(1) The Pareto chart method should be selected for analysis. (2) Main quality issues: honeycombing and pitting on the surface of precast components, as well as localized exposure of rebar. Treatment method: ① Scrub the rough areas with clean water; once thoroughly moistened, smooth them out using cement slurry or 1:2 cement mortar. ②Clean the concrete and rust from the exposed rebar, then smooth it out by applying 1:2 cement mortar. If the exposed reinforcement is deep, the weak concrete should be removed and cleaned thoroughly; then it should be compacted with concrete of a higher grade containing aggregate, followed by proper curing. ③The small cells can be first rinsed thoroughly with water, and then repaired using 1:2 cement mortar ； For large honeycombs, loose stones and protruding particles must first be removed and the structure shaped into a trumpet shape; it should then be rinsed thoroughly with clean water, compacted using concrete of a higher grade, and given proper curing.
(1) Given the characteristics of this problem, the construction unit should choose the Pareto chart method for analysis. (2) Main quality issues: 1) Pareto chart. 2) Analysis: Through Pareto analysis, the main quality issues are honeycombing and pitting on the surface of prefabricated components, as well as local reinforcement exposure. ①The rough areas should be washed with clean water; once thoroughly moistened, they should be smoothed out using cement slurry or 1:2 cement mortar. ②Clean the concrete and rust from the exposed rebar, then smooth it out by applying 1:2 cement mortar. If the exposed reinforcement is deep, the weak concrete should be removed and cleaned thoroughly; then it should be compacted with concrete of a higher grade containing aggregate, followed by proper curing. ③The small cells can be first rinsed thoroughly with water, and then repaired using 1:2 cement mortar ； For large honeycombs, loose stones and protruding particles must first be removed and the structure shaped into a trumpet shape; it should then be rinsed thoroughly with clean water, compacted using concrete of a higher grade, and given proper curing.