EC2-Compliant Design Method
12Pages

Design method verified by Dept, of Civil & Structural Engineering, University of Sheffield

KSN Anchor Box Cost-effective slab-to-wall continuity system with four-step EC2-compliant design method In this document, Ancon details a four-step EC2-compliant design method for the use of its KSN Anchors at slab-to-wall connections subjected to a combination of shear and tensile loads. The design method has been developed by Ancon and independently verified by the Department of Civil and Structural Engineering at the University of Sheffield, UK. Ancon’s internally threaded KSN Anchors, supplied in a metal casing and used in combination with Bartec Plus parallel-threaded reinforcing bars,...

APPROVAL KSN Anchor 5061 Technical Approval TA 5061 Eliminates risks Virtually unlimited associated with on-site continuation bar length. bar straightening Suitable for EC2 lap lengths Reduces reinforcement congestion EC2 indented construction joint Simple to schedule. Fast to install Easy visual check of correct bar engagement Independently-verified design method

System Components KSN Anchor Box There are eight standard anchors in the KSN range. They are manufactured from highly reliable Cr-Mo alloy steel with a minimum 15% elongation. The head is formed by hot forging to minimise material usage and improve the strength characteristics. The anchor is subsequently machined to incorporate a metric thread. Independent tests have verified the direct pull out strength of the anchors. UK CARES have independently assessed the KSN Anchor, refer to CARES Technical Approval TA1-B 5061. Anchor Embedment Length heff* When used for shear connections, KSN...

Slab Reinforcemente> Bartec Plus Continuation Bars Unlike re-bend continuity systems where bar lengths are restricted to the box dimensions, there is virtually no restriction on continuation bar length with KSN Anchors. Ancon KSN Anchors are designed for use with 12mm, 16mm and 20mm diameter grade B500B or B500C reinforcing bar, threaded with a metric thread, supplied by Ancon. The Bartec Plus system produces a full strength joint. The bar end is cut square and enlarged by cold forging. This increases the core diameter of the threaded portion of the bar to ensure that the strength of the...

Design Method The design method for slab-to-wall connections subjected to a combination of shear and tensile loads was developed by Ancon in collaboration with the Department of Civil & Structural Engineering at the University of Sheffield. It is to be adopted for the use of KSN anchors under predominant shear load conditions and makes reference to the following design codes: • BS EN 1992-1-1-1: Eurocode 2 • prEN 1992-4:2013 • ETAG 001-1997 Annex C The design method is aimed at providing continuity to the structure through simply-supported slabs: all relevant anchorage and shear checks are...

The tensile capacity NRd of the KSN system required to resist the tie force, expressed per linear metre of construction joint, is determined as follows: • In accordance with clause 7.2.1.3 of prEN 1992-4:2013, the tensile capacity for steel NRk,s is determined using the equation NRk,s = ΣKSN As 1.15 fyk / γMs , where: ΣKSN is the number of KSN anchors per linear metre of joint; γMs is taken as 1.4. It must also be checked that the spacing of the KSN anchors matches the spacing of primary reinforcing bars within the slab section at the support location. • In accordance with clause 7.2.1.4 of...

Step 3: Available Shear Capacity for KSN System after Deduction of Tie Force • In accordance with clause 7.2.3.1 of prEN 1992-4:2013 - table 7.3, the available capacity for steel VRd,s must fulfil the following equation: VRd,s = V(1-(NEd / Value E)2). Value H • In accordance with clause 7.2.3.1 of prEN 1992-4:2013 - table 7.3, the available capacity for concrete VEd,c must fulfil the following equations: VRd,c = (1-(NEd / (min. of Value F and G))35)2/3. Value J • In accordance with clause 6.2.5 of BS EN 1992:2001, the available shear capacity at wall-slab interface is determined as...

Design Example

Mid Slab Anchor ConnectionWall-Part Edge Elevation KSN Anchor Box Slab Reinforcement(A Projecting rebar with Bartec Plus threaded end to suit KSN Anchor Length calculated in accordance with BS EN 1992 Length derived from Bartec Plus continuation bar dimensions shown on page 5 Note A The U shaped end rebars to be 12mm diameter minimum. The bars may be formed from the top steel reinforcement. Horizontal rebar 120 at 200mm maximum centres Installation Guidance The Bartec Plus parallel-threaded continuation bars are inserted into the KSN Anchors and hand-tightened until fully locked using a...

Design Sheet - KSN Anchor Box Please provide: contact details; project details and design conditions • Reinforcement yield stress = 500 N/mm2 • Standard KSN Anchor Box is used (15mm/17mm rebate depths) 2. Design Conditions Please enter values in all boxes mm Concrete grade Slab top reinforcement provided at support Slab bottom reinforcement provided in span Vertical shear at joint VEd Horizontal tie force at joint T Email to: concrete@ancon.co.uk Ancon Ltd, President Way, President Park, Sheffield S4 7UR, United Kingdom Tel: +44 (0)114 238 1410, Web: www.ancon.co.uk

Ancon President Way, President Park Sheffield S4 7UR United Kingdom Tel: +44 (0) 114 275 5224 Email: inf^aneon.eo.uk www.ancon.co.uk