1913.5 Preconstruction Tests

A test panel shall be shot by each nozzleman and then, cured, cored or sawn, examined and tested prior to commencement of the project. The sample panel shall be representative of the project and simulate job conditions as closely as possible. The panel thickness and reinforcing shall reproduce the thickest and most congested area specified in the structural design. It shall be shot for each proposed concrete mix, at the proposed angles. The equipment used in preconstruction testing shall be the same equipment used in the work requiring such testing, unless substitute equipment is approved by the commissioner. Cores taken from the test panel shall be used to demonstrate that the proposed mix design meets the requirements of the construction documents and this code. All sampling and testing of shotcrete shall be performed by a licensed concrete testing laboratory. Construction of the test panels shall be witnessed by the special inspection agency responsible for the shotcrete construction.

Six core samples shall be obtained from each preconstruction test panel:

1. Three specimens with no reinforcing shall be sampled and prepared in accordance with ASTM C 42; and
2. Three specimens with reinforcing steel.

The licensed concrete testing laboratory that sampled the preconstruction test panels shall test the core specimens with no reinforcing in accordance with ASTM C 39.

The shotcrete test panel strength shall be deemed acceptable if the mean compressive strength of the set of three cores shall equal or exceed f'_c with no individual core less than 0.75 f'_c.

Core samples and/or test panels shall be cut with reinforcing steel and shall be visually evaluated by the registered design professional of record for the structural design, or a registered design professional acceptable to the registered design professional of record for the structural design. The nozzleman shall not proceed with work if cores and/or sections cut show the rebar not to be encapsulated with concrete to the satisfaction of the registered design professional of record for the structural design.