Effects of diameter, embedment depth and edge distance to tensile force on the chemical anchors

Chemical anchors are frequently used in reinforcement of existing structures and addition of new elements. Tensile strength of chemical anchors was effected by many parameters such as anchor diameter, edge distance, embedment depth, the chemicals used for bonding and cleaning and humidity conditions of the anchor hole. In the present study, epoxy based chemical adhesives were used to embed 80 anchors consisting of S420 outfits with an average compressive strength of 27 MPa. These anchors were then subjected to tension test. Anchors were embedded to depths determined as 5, 10, 15 and 20 times of diameter and with an edge distance determined as 5, 7.5, 10, 15 and 20 times of diameter. Load and displacement values are measured during experiments and load-displacement graphics were drawn and collapse modes were determined. Experiments were evaluated based on anchor diameter, embedment depth and edge distance. Results were compared to capacity and strength values estimated due to ACI 318 App-D and safety coefficient was determined accordingly. Evaluation of experimental study showed an increase of tensile strength with increasing anchor diameter and edge distance and the increase of tensile strength has increased until an embedment depth which was 15 times (cm) of diameter. Comparison of design strength estimated by ACI 318 App-D and experimental results indicated that safety coefficient had decreased with increasing diameter. Key Words: Chemical Anchors; Tensile Strength; ACI 318