Are you getting nonsensical values? Are you getting some sort of exception? I don't really know what problem you're having.
As a reference, we initialized the accelerometer like this:
Code:
ADXL345_I2C _accelerometer = new ADXL345_I2C(1,ADXL345_I2C.DataFormat_Range.k2G);
and read from it like this:
Code:
double yAccel = _accelerometer.getAcceleration(ADXL345_I2C.Axes.kY);