Briefly describe the structure of handrails and railings

Railings and handrails are calculated by extension meters. Except for the balcony railings, their lengths can be calculated by multiplying the horizontal projection length by a factor of 115, excluding the length of the part extending into the wall. The coefficients cannot be used for the railings and handrails on the balcony. This is because the handrails of the stairs are obliquely long. According to the geometric principle and the projection relationship, the oblique length of the space cannot reflect its actual length when it is horizontally projected.

Therefore, for the sake of simplicity in calculation, the principle that the hypotenuse of a right triangle is longer than the straight side is used, and the comprehensive coefficient is 115. If the actual stair angle is different, the actual length of the handrail will also be different, but the quota is the comprehensive coefficient.

The actual difference is not allowed to be adjusted, and it is implemented according to the quota. The coefficient of 115 cannot be used for the handrails and railings of the balcony, and the length of the part extending into the wall cannot be used as the calculated length. The elbow in the stair handrail, at the turn of the parallel stairs, when the first step of the ascending and descending sections is flush, in order to maintain the same height of the handrails of the ascending and descending sections, the handrails are often set within the edge. half a step wide.

However, if the width of the passage is not changed, the railing should be set close to the edge, but at the same time, the height difference will be formed between the upper and lower stair handrails. The method of crane top handrail is often used to deal with it. By staggering the sections by one step, the above two problems can be solved, but at the same time, the depth of the stairwell can be increased. The elbows are calculated individually, and the bending quota items are set.