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Carbon Fiber Reinforced Polymer (CFRP)
Aslan 500 Carbon Fiber Reinforced Polymer (CFRP) Tape is used for structural strengthening of concrete, masonry or timber elements using the technique known as "Near Surface Mount" or NSM strengthening.
Features of Aslan 500 CFRP Tape Aslan 500 is a 2mm X 16mm "tape" designed specifically for NSM strengthening. It is made from 700ksi, 33Msi carbon fiber, 60% by volume in a Bisphenol Epoxy Vinyl ester resin matrix. A surface treatment is applied to the wide faces of the CFRP Tape to enhance the bond characteristics when used with structural epoxy adhesives or cementitious latex modified grouts. The nominal "diameter" or cross sectional area of Aslan 500 is the same as a #2 or 1/4" diameter rod. It is furnished in continuous lengths in spools that are 250ft (76m) long. 
Tensile strengths shown are the average minus three standard deviations. Per ACI440, this value is f*fu, the guaranteed tensile strength. Tensile Modulus of Elasticity values are the average of a population of test specimens as per ACI440 guidelines.
Coefficient of Thermal Expansion:Transverse Direction ..... 41 to 58 X 10-6/F (74 to 104 X 10-6/C)Longitudinal Direction... 4 to 0.0 X 10-6/F (-9 to 0.0 X 10-6/C) Barcol Hardness:48 - 55 per ASTM D2583Unlike steel materials, the stress-strain curve of FRP materials is linear elastic to failure.
NSM Design  Recommended Structural Adhesives include:
NSM Design Example - BASEMENT WALL STRENGTHENING The following example shows the strengthening of a basement wall subjected to a maxium of 305 lbs per square foot of earth pressure. In this instance, since the earth force will be sustained against the basement wall, the use of CFRP Tape is desirable. ObjectiveThe design specifications are in compliance with ACI 440.1R-01, hereafter referred to as ACI 440 and ACI 530-02/ASCE 5-02/TMS 402-02, hereafter referred to as ACI 530 reported by the Masonry Standard Joint Committee, and Masonry Designer's Guide (MDG)MaterialsTable 1 presents the properties of concrete masonry, and carbon (CFRP) tapes.
Design ConsiderationsThe design of the strengthening follows Allowable Stress Design (ASD). Thus, according to ACI 530 and MDG, the following parameters were computed for the masonry:
where Fb, Fv and Em represent allowable compressive strength, shear strength and modulus of elasticity of the masonry, respectively. The design properties used for the FRP reinforcement are expressed as follow:
where ffu and ff-all are the ultimate design strength and allowable design strength of FRP reinforcement, CE is the environmental reduction factor as reported in ACI 440 (Table 7.1), and k gives the percentage of the ultimate to define the allowable stress of the FRP reinforcement. A value of k equal to 0.3 is used in the case of the CFRP tape in order to avoid premature modes of failure. Design modulus of elasticity of FRP is taken as indicated by the Hughes Brothers. Table 2 summarizes the assumed design properties for FRP.
External LoadsThe pressure exerted to the wall by the earth is considered to have a triangular distribution, with the maximum pressure w=305 psf at the bottom of the wall.AnalysisThe structural analysis is carried out considering that the wall is simply supported (see Fig 1).
Maximum bending moment is expressed as (Eq. (3)): 
(3)
Maximum shear force due to the applied load is expressed as (Eq.(4)): 
(4)
The amount of FRP needed to satisfy the load demand is one CFRP Tape every 24 in. This spacing of 24 in. does not exceed the maximum spacing recommended by MDG (four times the wall thickness).
A sketch of the reinforcement placed into the masonry blocks is depicted:
  Installation
Installation (con't.)
Strengthening
During the summer of 2002, the Martin Spring Bridge near Rolla Missouri was strengthened using Aslan 500 CFRP Tape. Load testing of the bridge verified the effectiveness of the NSM methods and bridge posting limits were removed. (upper right) Concrete beam without shear stirrups, designed to fail in shear was strengthened with Aslan 500 as part of undergraduate reinforced concrete design coursework. The resulting failure mode after strengthening was yielding of the longitudinal reinforcing steel. (right) 
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