sdaiPutADBTypePath

public const string ifcenginedll = @"ifcengine.dll";

[DllImport(IFCEngineDLL, EntryPoint = "sdaiPutADBTypePath")]
public static extern void sdaiPutADBTypePath(int_t ADB, int_t pathCount, string path);

[DllImport(IFCEngineDLL, EntryPoint = "sdaiPutADBTypePath")]
public static extern void sdaiPutADBTypePath(int_t ADB, int_t pathCount, byte[] path);    

using RDF;      //  include at least engine.cs within your solution

//
//  #13131 = IFCMEASUREWITHUNIT(IFCPLANEANGLEMEASURE(1.745E-2), #31313);
//  #31313 = IFCSIUNIT(*, .PLANEANGLEUNIT., $, .RADIAN.);
//

Int64 buildSIUnitInstance(Int64 model, string UnitType, string Prefix, string Name)
{
    //  #31313 = IFCSIUNIT(*, .PLANEANGLEUNIT., $, .RADIAN.);
    Int64 ifcSIUnitInstance = ifcengine.sdaiCreateInstanceBN(model, "IFCSIUNIT");

    ifcengine.sdaiPutAttrBN(ifcSIUnitInstance, "UnitType", ifcengine.sdaiENUM, UnitType);
    if (Prefix != null)
    {
        ifcengine.sdaiPutAttrBN(ifcSIUnitInstance, "Prefix", ifcengine.sdaiENUM, Prefix);
    }
    ifcengine.sdaiPutAttrBN(ifcSIUnitInstance, "Name", ifcengine.sdaiENUM, Name);

    return ifcSIUnitInstance;
}

Int64 buildMeasureWithUnitInstance(Int64 model)
{
    Int64 valueComponentADB;
    double valueComponent = 0.01745;

    //  #13131 = IFCMEASUREWITHUNIT(IFCPLANEANGLEMEASURE(1.745E-2), #31313);
    Int64 ifcMeasureWithUnitInstance = ifcengine.sdaiCreateInstanceBN(model, "IFCMEASUREWITHUNIT");

    valueComponentADB = ifcengine.sdaiCreateADB(ifcengine.sdaiREAL, ref valueComponent);
    ifcengine.sdaiPutADBTypePath(valueComponentADB, 1, "IFCPLANEANGLEMEASURE");
    ifcengine.sdaiPutAttrBN(ifcMeasureWithUnitInstance, "ValueComponent", ifcengine.sdaiADB, ref valueComponentADB);

    ifcengine.sdaiPutAttrBN(ifcMeasureWithUnitInstance, "UnitComponent", ifcengine.sdaiINSTANCE, buildSIUnitInstance(model, "PLANEANGLEUNIT", null, "RADIAN"));

    return ifcMeasureWithUnitInstance;
}