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Structural Engineering: What is negative moment /positive moment at supports/midspan?
Can you explain to me what negative moment and positive moment mean in structural engineering, particularly at supports and midspans?
Sure! In structural engineering, moments refer to the force that causes an object to rotate. A positive moment occurs when the resulting rotating force is in the same direction as the normal orientation of the object, while a negative moment occurs when the force is in the opposite direction. 

At supports, a positive moment indicates a downward force, while a negative moment indicates an upward force. At midspans, a positive moment indicates that the object is bending downward, while a negative moment indicates that it is bending upward.