ICC Prestressed Concrete SI case studies
ICC Prestressed Concrete SI · Put your knowledge to work in context.
The ICC Prestressed Concrete Special Inspector (SI) certification is a credential for inspectors who verify precast, prestressed concrete elements - both in the fabrication plant and in the field. It is aimed at quality-control technicians, plant inspectors, field inspectors, testing-lab staff, and engineering technicians who check pretensioned and post-tensioned members against approved drawings, specifications, and referenced standards. The ICC Prestressed Concrete SI case studies are 5 cases and about 2,580 words.
1Low Strand Elongation in a Pretensioning Bed
At a long-line pretensioning plant, a 15.2 mm seven-wire low-relaxation strand (nominal area 140 mm², certified Ep = 195 GPa, fpu = 1,860 MPa) is tensioned in a 91.4 m bed to 0.75fpu, or 195.3 kN. The jack gauge was last calibrated 13 months ago; the plant's annual calibration is due.
557 words, about 3 min2Transfer Strength and Steam-Curing Temperature Nonconformance
A precast plant produces 400 mm deep prestressed hollow-core slabs with a mix containing 420 kg/m³ Type III cement, 7% silica fume, w/cm 0.32, and a polycarboxylate retarder. The specified transfer strength is 32 MPa.
503 words, about 3 min3Under-Capacity Four-Point Lift of a Prestressed Box Girder
At an erection site, a 30.0 m prestressed concrete box girder weighs 540 kN and has four cast-in lifting inserts, each rated 150 kN for a vertical lift. The contractor plans a four-point lift with slings at 45° to the horizontal, using a single crane hook and a spreader beam that is not equalizing.
525 words, about 3 min4Anchorage Component Mismatch and Abnormal Wedge Pull-In
During post-tensioning of a 20 m span transfer girder, the inspector notices that one 12-strand tendon using 15.2 mm strand takes 12 mm of wedge pull-in at the live end, while the other five tendons take 5-6 mm. The tendon is specified as a 15.2 mm system, but the wedge marks on the strand are shallower and the anchor head has a different stamp than the approved submittal.
494 words, about 2 min5Expired Gauge Calibration and Missing Strand Traceability
An inspector audits a prestressed pile plant producing 400 mm square piles. The plant's stressing gauge calibration is dated 14 months ago; the calibration interval in the quality manual is 12 months.
501 words, about 3 min