Landscape membrane structure as the outdoor landscape architecture, natural need to consider the load and stress distribution under various climate conditions. Due to the membrane material is a new kind of building materials, flexible it has a certain scale, the membrane surface under the action of load, there will be some deformation, so the landscape membrane structure architecture to "rain" and "snow" is more sensitive. Membrane structure of architectural design and structural design stage must be fully aware of the "water" and "snow" problem. Otherwise, leave a lot of hidden dangers. Past a lot of landscape membrane structure engineering accident, this problem is one of the main cause of the accident.

From the concrete operating level, the landscape design of membrane structure should be used according to the structure of the characteristics and general layout requirements, reasonable slope drainage and drainage position, ensure catchment is smooth at the membrane surface; In snow load larger areas, should adopt the larger slope at the membrane surface and the necessary snow prevention measures.

Landscape drainage design of membrane structure can be used without drainage or organized drainage way. Because of his strange landscape of the modelling of membrane structure, free surface, the reasonable way of modelling and drainage should be considered.

Large public membrane structure architecture (more than 3000 ㎡), should adopt organized drainage; Small open membrane structure architecture (below 500 ㎡) can take disorganized drainage; Medium-sized public buildings (500 ~ 3000 ㎡) membrane appropriate according to its height, closed and open sex, select the appropriate drainage form, can be partly free drainage, drainage combined with organization.

The rain water at the membrane surface is designed on the basis of the drainage system, its size and the degree of the local rainstorm q, the catchment area of A proper drainage capacity coefficient k and the membrane surface, according to the following formula

Qr = k1 (A.q 5/1000)

Type of qr - rain design flow

A - catchment area (㎡), based on the characteristics of the membrane surface calculation;

Q5 - local rainfall duration rainstorm intensity of 5 min

K1 - design return period is 1 a appropriate drainage capacity coefficient of the membrane surface (slope at the membrane surface is less than 10% when desirable k1 = 1.0, when the slope is greater than 10% in 1.2 ~ 2.0).

The rainstorm intensity can be calculated at the following formula

H = (1 + C.t F ant0)/n (t + b)

Type of h - storm (rain) intensity (mm/min)

T0 - design return period (a)

T - rainfall duration (min)

F, C, b, n - local rainfall parameters.

The membrane surface drainage slope demand is greater than the general construction. Slope more than 15 ~ 20% flat membrane, hyperboloid ridge (curvature) should be greater than 10%. At the same time the membrane surface tension 1.0 ~ 2.0 KN/m above, avoid membrane in the rain under the action of large deformation, so as to produce water, dripping water on the membrane surface. Membrane area of water has Matthew efficiency characteristics, water will lead to partial concave deformation, concave deformation in turn aggravate water phenomenon. Enough slope, curvature and the tension level is the necessary condition to ensure catchment is smooth. Water board (for stainless steel, aluminum plate, membrane belt), gutters, downspouts design should be coordinated with membrane node structure design.