I was pulling into a parking spot in a parking garage and pressed on the brake. The brake pedal did not offer the usual resistance and went flat to the floor. The car began to accelerate and smashed into a concrete I-beam on the wall of the garage. I put the car in park and kept my foot on the brake but it still kept trying to move forward. Then I put it in reverse and it slowly backed away from the wall but still wouldn’t stop with the brake applied and in park. I pulled the emergency brake on and the car stopped and then I turned off the engine.