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The program DC-Nail analyzes ground nailings. The analysis is performed according to the Method of the Kinematic. Elements with a block sliding mechanism. The program calculates the necessary nail lengths and determines the nail forces by the block sliding, as well as by the nail-wall dimensioning. Concerning the safety definition the program applies the concept of the authorization of the Institute für Bautechnik, Berlin. Alternatively partial safety factors may be applied following DIN 1054:2005 or SIA 267 or any approach may be set by free standard definition. The following check calculations are done:
1. Check of the internal and external stability a) Safety against sliding inside and below the nailed earth block b) Safety against overturning (not definite for usual nail walls, may be dropped) c) Bearing capacity acc. to DIN 4017:1979, DIN 1054:2005 with DIN 4017:2006 and SIA 267 d) Sliding block analysis Determining of the most unfavorable sliding line by variation of the angle of inclination θ. Definition of the safety by comparison of the resistances and loads in the sliding line under the angle θ The necessary safety factor is given as: η ≥ 2.0 (Load case 1 = final state) η ≥ 1.5 (Load case 2 = construction stage) Please note that according to the authorization the check has to be done that the nail forces may be transferred into the soil with a safety of 2.0. As the available safety is defined as the relation between the possible and the available nail forces, for the stability analysis in construction stages the necessary safety should also set to 2.0. For the analysis with partial safety factors no necessary safety needs to be defined, but for the loads and resistances multiplied with the partial safety factors the proof Ed/Rd ≤ 1.0 has to be checked. The analysis has to be done for: construction stages (Lc 2) final state (Lc 1). e) Analysis of slope stability following DIN 4084 This check has to be done and is of great importance if below the nailed soil block layers with a lower shear capacity are present. DC-Software DC-Nail 6
2. Proof of the nails maximum nail forces from sliding block analysis (Lc1/Lc2) maximum nail forces from the analysis of the shotcrete wall a) Steel stress „inner nail safety“ σ < βs/1.75 for global safety resp. βs/1.15 for partial safety factors b) Transfer of the nail forces into the soil max. Tm / erf. Tm ≥ 2 „external nail safety“
3. Shotcrete wall Dimensioning following DIN 1045, DIN 1045-1, SIA 262 or ÖNORM B 4700 for 0.85-fold active earth pressure rectangular distribution (alternatively) a) Calculation of the outer and inner reinforcement b) Proof against punching (Hint: Block-outs in the punching area (e.g. drain pipes, are not allowed in the check).
Brochure
Video
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BROCHURE_DC_NAIL.pdf 
DCNail.wmv