Prestressed CFRP strip is a good reinforment method for construction structural strengthening .We must metion these following points:
(1) Cutting of prestressed carbon fiber laminate, should adopt the wheel saw, shall not use arc cutting;
(2) Stranding should be straighten out, bundled into a bundle, not disorder;
(3) The equipment and instruments for the application of prestressing CFRP strips shall be maintained and calibrated on a regular basis;
(4) The pre-stressed tendons should be provided the tensile strength test report before tensile . When the compressive strength of concrete to meet the design requirements, and not less than 75% of the design strength level;
(5) Before the prestressed tendons are tensioned, the pressure plate should be cleaned and the quality of the concrete behind the pressure plate should be checked. If there is a hollow phenomenon in the concrete, it should be repaired with epoxy mortar ;
(6) Anchor installation, the anchor plate should be positive, the clip should be tightened, and the chip to be uniform;
(7) Before the large tonnage prestressed tendons, the professional staff should try to pull first;
(8) Prestressed tendons should be loaded from zero to the initial pull of the starting point of the measured elongation at the time of tensioning, and then graded to the desired tension;
(9) To control the prestressed tendors ,we must take stress control, elongation check;
(10) The pipe grouting requirements of dense, cement slurry strength level should not be lower than C30.
(11) With the connector connected to the multi-span continuous prestressing tendons of the pipe grouting, should be finished over a cross-perfusion cross-span, not in the cross after the end of all the grouting;
(12) Prestressed tendons anchored after the exposed length, not less than 30mm, anchor with the application of end-capped concrete protection.
(13) tool clip for the three-piece, working clip for the two, the two can not be mixed. Work anchor can not be used as a tool anchor can not be reused;
(14)The anchor must keep properly, no rust, water and contaminated other debris.
(15) Tension should do a safety measure.
(16) The anchor system should be used together;
(17) Prestressed construction should be construct by a professional construction team, and the construction personnel should be trained in professional training.