Asymmetric cable-membrane tensegrity structure of opening type, method of constructing the same and method of designing the same

Abstract

A cable-membrane tensegrity structure which is asymmetric, and construction method and design method thereof are provided. The cable-membrane tensegrity structure comprises a central opening and is formed by a ring cable (4) and three layers of radial cables comprising a suspension cable (1), a ridge cable (2) and a valley cable (3), wherein the suspension cable (1) is located above the ridge cable (2), the ridge cable (2) is located above the valley cable (3), wherein one end of each of the suspension cable (1), the ridge cable (2) and the valley cable (3) is connected to the ring cable (4), and the other end of each of the suspension cable (1), the ridge cable (2) and the valley cable (3) is connected to a peripheral supporting structure (7), wherein a coating membrane (5) is tensioned between the ridge cable (2) and the valley cable (3) that are adjacent to each other and function as a skeleton to tension the coating membrane (5). The method of constructing the cable-membrane tensegrity structure comprises steps of: lifting step by step the suspension cable (1), the ridge cable (2) and the valley cable (3) to positions adjacent to respective cable anchor nodes by a traction device, based on a shape of formed cable-membrane tensegrity structure; and tensioning and anchoring synchronously the suspension cable (1), the ridge cable (2) and the valley cable (3) in place by a tensioning device, so as to achieve a final shape of the cable-membrane tensegrity structure. A multi-stage design method, based on the bearing whole-process, of a cable-membrane tensegrity structure of an opening type is also provided.

Claims

1. A multi-stage design method, based on a bearing whole-process, of a pre-stress cable-membrane tensegrity structure, the cable-membrane tensegrity structure comprising a central opening and being formed by three layers of radial tension cables and a ring cable, the three layers of radial tension cables comprising a layer of suspension cable, a layer of ridge cable and a layer of valley cable, wherein the suspension cable is located above the ridge cable, the ridge cable is located above the valley cable, inner end of each of the suspension, ridge and valley cables is connected to the ring cable, and the other end of each of the suspension, ridge and valley cables is connected to a peripheral supporting structure, a coating membrane is tensioned between the ridge cable and the valley cable that are adjacent to each other and function as a skeleton to tension the coating membrane; wherein based on structural nonlinear characteristics of the pre-stress cable-membrane tensegrity structure of an opening type during the bearing whole-process, sequentially dividing a structural-mechanics-response change process into following stages of: stage {circle around (1)}, that is, an elastic stage, a load is increased from a structure formation state under a pre-tension stress and a self weight to a normal structure formation state under a permanent load and one times of variable load, a tension stress of the valley cable is decreased, a tension stress on suspension and ridge cables is linearly increased, and the ring cable deforms nonlinearly and vertically; stage {circle around (2)}, the valley cable is loosened or the tension stress of the valley cable is decreased to a minimum, the tension stress of the suspension and ridge cables is linearly increased, and the ring cable nonlinearly vertically deforms with a maximum vertical-deformation incremental times larger than a load incremental times; stage {circle around (3)}, the valley cable is tightened again, the tension stress on all tension cables is linearly increased, and the ring cable nonlinearly vertically deforms with the maximum vertical-deformation incremental times less than the load incremental times; stage {circle around (4)}, the tension stress of the tension cables is nonlinearly increased with a stress incremental times less than the load incremental times until the tension cables are tensioned to be broken, and the ring cable nonlinearly vertically deforms with the maximum vertical-deformation incremental times less than the load incremental times until the structure is failed in bearing capacity, wherein the load incremental times is a ratio of an applied load to the one times of variable load (P.sub.1); the vertical-deformation incremental times is a ratio of the ring cable vertical deformation under the permanent load and the applied load to the ring cable vertical deformation under the permanent load and the one times of variable load; the stress incremental times is a ratio of the tension cable stress under the permanent load and the applied load to the tension cable stress under the permanent load and the one times of variable load; the applied load is the load applied on the structure except for the permanent load; the terms of valley is loosened means that the tension stress of the valley cable is equal to 0.

2. The method according to claim 1, wherein: a structure material model is set to have a nonlinear property during the bearing whole-process of the pre-stress cable-membrane tensegrity structure of an opening type; a pre-tension stress loss of tension cable and a cable clamp anchor node restriction rigidity are considered in a calculation model based on a test result, and a structural system geometrically nonlinear is also considered during calculating; a large universal finite element program is adopted to analyze and a Newton-Raphson nonlinear iteration strategy is used to solve equations.

3. The method according to claim 2, wherein determining a relation among various parameters in the structural system during the bearing whole-process is based on the calculation model and a calculation method.

4. The method according to claim 1, comprising step 1: determining parameters including the following: cable elastic modulus, yield strength, limit strength 6.sub.u, linear expansion coefficient, cable clamp anchor node friction factor and cable clamp anchor node restriction rigidity; building up a simulation calculation model conforming to a building by means of a computer soft, and inputting the parameters into the simulation calculation model to perform the bearing whole-process of the pre-stress cable-membrane tensegrity structure of an opening type, wherein a pre-tension stress of tension cable is 6.sub.0; and determining mechanical response stages of the respective structures, and drawing related structural response curves.

5. The method according to claim 4, further comprising step of: checking the cable elastic modulus, the yield strength, the limit strength 6.sub.u, the linear expansion coefficient, the cable clamp anchor node friction factor and the cable clamp anchor node restriction rigidity by means of mechanics experiment.

6. The method according to claim 4, wherein the pre-tension stress of tension cable 6.sub.0 is in a range of 0.26.sub.u-0.36.sub.u.

7. The method according to claim 4, further comprising step 2: based on the stage {circle around (1)}, that is, the elastic stage, under an action of the permanent load and the one times of variable load, calculating the tension cable stress 6.sub.1, and determining whether the tension cable stress 6.sub.1 satisfies a safety condition regarding bearing stress in stage {circle around (1)}: 0<6.sub.1(0.35-0.5)6.sub.u; calculating a vertical deformation value d.sub.1 of the ring cable and a curve angle .sub.1 of the vertically deforming valley cable, wherein d.sub.1 is the vertical deformation value of the ring cable under the action of the permanent load and the one times of variable load (P.sub.1), .sub.1 is an angle of a tangent line at any point of a valley cable curve with respect to a horizontal line after the valley cable vertically deforms under the action of the permanent load and the one times of variable load, and determining whether vertical deformation value d.sub.1 and the angle .sub.1 satisfy a safety condition regarding vertical deformation capacity in stage (1): d.sub.1[d.sub.1], .sub.1[], in which [d.sub.1] is an allowable maximum vertical deformation value for the ring cable under the action of the permanent load and the one times of variable load according to membrane structure building using requirements, [] is an allowable minimum curve angle for the valley cable after the valley cable vertically deforms under the action of the permanent load and the one times of variable load, if determining result is yes, then it is determined that the pre-tension stress of tension cable 6.sub.0 is suitable, if determining result is not, then adjusting the pre-tension stress of tension cable 6.sub.0, or changing an arrangement of the structure, or increasing tension cable rigidity or bearing capacity, and redesigning based on the step 1 and the step 2 until the safety condition regarding vertical deformation capacity in stage (1) is satisfied.

8. The method according to claim 7, wherein [d.sub.1] is set to be equal to L/(60-85), wherein L is a cantilever length of the pre-stress cable-membrane tensegrity structure of an opening type; [] is in a range of 5-7 degrees.

9. The method according to claim 7, further comprising step 3: based on the structure response stage {circle around (2)} where the valley cable is loosened or the tension stress thereof is decreased to the minimum, determining whether the load incremental times P.sub.s/P.sub.1 satisfies a safety condition regarding elastic bearing capacity in stage {circle around (2)}: P.sub.s/P.sub.1K.sub.s, wherein K.sub.s is the system elastic bearing capacity coefficient; determining whether an elastic vertical deformation capacity coefficient d.sub.s/d.sub.1 satisfies a safety condition regarding elastic vertical deformation capacity in stage {circle around (2)}: d.sub.s/d.sub.1(P.sub.s/P.sub.1), wherein is a coefficient, d.sub.s is a ring cable vertical deformation value under the applied load (P.sub.s) when the valley cable is loosened or the tension stress thereof is decreased to the minimum, if the safety condition regarding elastic bearing capacity or the safety condition regarding elastic vertical deformation capacity in the step 3 is not satisfied, then adjusting the initial tension force of the tension cable, or increasing tension cable rigidity or bearing capacity, and redesigning based on the step 1, the step 2 and the step 3 until the safety condition regarding elastic bearing capacity and the safety condition regarding elastic vertical deformation capacity in the step 3 are satisfied.

10. The method according to claim 9, wherein
K.sub.s=1.31.8;
=1.01.2.

11. The method according to claim 9, further comprising step 4: based on the structure response stage {circle around (3)}, determining whether the load incremental times P.sub.y/P.sub.1 when the tension cable is yielded satisfies a safety condition regarding system yield bearing capacity in stage {circle around (3)}: P.sub.y/P.sub.1>K.sub.y, wherein K.sub.y is the system yield bearing capacity coefficient and P.sub.y is the load applied on the structure when the tension cable is yielded; calculating the ring cable vertical deformation value d.sub.y and the valley cable vertical deforming curve angle .sub.y when the tension cable is yielded, and determining whether the deformation value d.sub.y and the curve angle .sub.y satisfy a safety condition regarding vertical deformation capacity in stage {circle around (3)}: d.sub.y[d.sub.y], .sub.y[.sub.y], wherein [d.sub.y] is an allowable maximum vertical deformation value for the ring cable when the tension cable is yielded, and [.sub.y] is an allowable minimum curve angle when the tension cable is yielded after the valley cable deforms, and wherein [.sub.y]0; if the safety condition regarding system yield bearing capacity or the safety condition regarding vertical deformation capacity in the step 4 is not satisfied, it needs to adjust the initial tension force of the tension cable, or increase tension cable rigidity or bearing capacity, and redesign based on the step 1, the step 2, the step 3 and the step 4 until the safety condition regarding system yield bearing capacity and the safety condition regarding vertical deformation capacity in the step 4 are satisfied.

12. The method according to claim 11, wherein
K.sub.y=5.06.5; [d.sub.y]=L/(12-20), wherein L is a cantilever length of the pre-stress tensegrity structure of an opening type.

13. The method according to claim 11, further comprising step 5: based on the structure response stage {circle around (4)}, determining whether the load incremental times P.sub.u/P.sub.y corresponding to tension cable limit breaking satisfies a safety condition regarding system limit bearing capacity in stage {circle around (4)}: P.sub.u/P.sub.y>K.sub.u, wherein K.sub.u is system bearing capacity ductility coefficient and P.sub.u is the load applied on the structure when the tension cable is in a condition of limit breaking; calculating the ring cable vertical deformation value d.sub.u corresponding to the tension cable limit breaking, and determining whether the system vertical deformation capacity ductility coefficient d.sub.u/d.sub.y satisfies a safety condition regarding system limit vertical deformation capacity in stage {circle around (4)}: d.sub.u/d.sub.y(P.sub.u/P.sub.y), wherein d.sub.u is the ring cable vertical deformation value corresponding to the tension cable limit breaking; if the safety condition regarding system limit bearing capacity or the safety condition regarding system limit vertical deformation capacity in the step 5 is not satisfied, it needs to adjust the initial tension force of the tension cable, or increase tension cable rigidity or bearing capacity, and redesign based on the step 1, the step 2, the step 3, the step 4 and the step 5 until the safety condition regarding system limit bearing capacity and the safety condition regarding system limit vertical deformation capacity in the step 5 are satisfied.

14. The method according to claim 13, wherein
K.sub.u=1.41.8.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above and other features of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the accompanying drawings, in which:

(2) FIG. 1 is a cross section view of a cable-membrane tensegrity structure according to an exemplary embodiment of the present invention;

(3) FIG. 2 is a three-dimensional view of a cable-membrane tensegrity structure according to an exemplary embodiment of the present invention;

(4) FIG. 3 is a local three-dimensional view of a cable-membrane tensegrity structure according to an exemplary embodiment of the present invention;

(5) FIG. 4 is a local cross section view of a cable-membrane tensegrity structure according to an exemplary embodiment of the present invention;

(6) FIG. 5 is an illustrative view of a first ring-cable-clamp anchor node connected to a valley cable and a suspension cable, according to an exemplary embodiment of the present invention;

(7) FIG. 6 is an illustrative view of a second ring-cable-clamp anchor node connected to a ridge cable, according to an exemplary embodiment of the present invention;

(8) FIG. 7 is an illustrative view of a ring truss or beam-suspension cable anchor node according to an exemplary embodiment of the present invention;

(9) FIG. 8 is an illustrative view of a ring beam-ridge cable anchor node according to an exemplary embodiment of the present invention;

(10) FIG. 9 is an illustrative view of a ring beam-valley cable anchor node according to an exemplary embodiment of the present invention;

(11) FIG. 10 is a flow chart of a construction method of an asymmetric open cable-membrane tensegrity structure system according to an exemplary embodiment of the present invention;

(12) FIG. 11 is an illustrative view of structure bearing whole-process load-mechanical response nonlinear iterative process, according to an exemplary embodiment of the present invention;

(13) FIG. 12 is a relationship curve between the applied load P and the ring cable vertical deformation d, according to an exemplary embodiment of the present invention;

(14) FIG. 13 is a relationship curve between the applied load P and the valley cable stress , according to an exemplary embodiment of the present invention;

(15) FIG. 14 is a relationship curve between the applied load P and the ring cable stress , according to an exemplary embodiment of the present invention;

(16) FIG. 15 is an illustrative view of the valley cable vertical deformation according to an exemplary embodiment of the present invention;

(17) FIG. 16 is an illustrative perspective view of a pre-stress tensegrity structure of an opening type according to an exemplary embodiment of the present invention; and

(18) FIG. 17 is a flow chart of multi-stage design method of a bearing whole-process of a pre-stress tensegrity structure of an opening type according to an exemplary embodiment of the present invention.

REFERENCE LIST

(19) Suspension cable-1, ridge cable-2, valley cable-3, ring cable-4, coating membrane-5, ring truss or beam-suspension cable anchor node-6, peripheral steel structure (or supporting structure)-7, ring beam-ridge cable anchor node-8, ring beam-valley cable anchor node-9, ring-cable-clamp anchor node connected to the valley and suspension cables-10, ring-cable-clamp anchor node connected to the ridge cable-11, membrane side cable-12.

(20) In FIG. 11, the horizontal ordinate d indicates the vertical deformation, the vertical ordinate P indicates the restoring force, subscript i indicates the i.sup.th step in the iterative process, P.sup. indicates the target load.

(21) In FIG. 12, the vertical ordinate d indicates the ring cable vertical deformation, the horizontal ordinate P indicates the applied load, and L indicates different structure response stages in bearing capacity whole-process analysis.

(22) In FIG. 13, the vertical ordinate .sub.g indicates the valley cable stress, the horizontal ordinate P indicates the applied load, and L indicates different structure response stages in bearing capacity whole-process analysis.

(23) In FIG. 15, .sub.1 indicates the valley cable curve angle after vertically deforming.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

(24) Exemplary embodiments of the present disclosure will be described hereinafter in detail with reference to the attached drawings, wherein the like reference numerals refer to the like elements. The embodiments described with reference to the drawings are only for demonstration and illustration and rather than for limitation.

(25) Hereafter, it will take a stadium project as an example to describe a cable-membrane tensegrity structure which is asymmetric and is of an opening type with reference to FIGS. 1-9.

(26) A peripheral supporting steel structure 7 is firstly built up, as shown in FIG. 2, the peripheral supporting steel structure is configured to be an X-typed post or a ring beam with a ring truss provided on the top thereof.

(27) A ring beam-suspension cable anchor node 6 is provided at the position where the top ring truss is connected to the suspension cable;

(28) A ring beam-ridge cable anchor node in the middle 8 and a ring beam-valley cable anchor node at the bottom 9 are provided at positions where the middle ring beam of the peripheral supporting steel structure 7 are connected to outer ends of the ridge cable 2 and the valley cable 3, respectively;

(29) According to the cable tension, a set of inner ring cables is composed of 10 inner ring cables 4 parallel to each other, the set of inner ring cables are divided into an upper layer and a lower layer, each layer of cables comprises 5 inner ring cables 4;

(30) The inner ring cables 4 are connected to inner ends of the suspension cable 1 and the valley cable 3 by means of the cable clamp anchor node 10;

(31) The inner ring cables 4 are connected to inner end of the ridge cable 2 by means of the cable clamp anchor node 11;

(32) The coating membrane 5 is tensioned among the ridge cables 2 and the valley cables 3 as well as the membrane side cables 11 to form the cable-membrane tensegrity structure which is asymmetric and is of an opening type.

(33) Hereafter, it will describe a method of constructing an cable-membrane tensegrity structure which is asymmetric and is of an opening type with reference to FIGS. 1-10.

(34) Exemplary Embodiment 1:

(35) It will take a stadium project as an example to describe the exemplary embodiment 1.

(36) (1) Performing the whole-process computer simulation analysis of tensioning pre-stressed tension cable, by taking a structure formation meeting design requirement as a target, taking whole tension of cable-membrane structure as a basic principle for tension construction, building up a whole structure calculation model by a computer, and inputting related structure parameters;

(37) using technical parameters, such as, the pre-stress of the tension cables, a cutting length of the cables and a sequence to tension the tension cables, for the tension construction;

(38) wherein the whole-process computer simulation analysis of tensioning pre-stressed tension cable considers structural system geometrical nonlinear, adopts a large universal finite element program and uses a Newton-Raphson nonlinear iteration strategy to solve equations.

(39) (2) Mounting the peripheral steel structure 7 from bottom to top, and mounting the ring beam-valley cable anchor node 9, the ring beam-ridge cable anchor node 8, and the ring beam-suspension cable anchor node 6;

(40) (3) Obtaining cutting lengths of the respective cables based on a result of the construction simulation analysis, and accurately cutting the ring cable 4 and the radial cables 1, 2, 3 based on the obtained cutting lengths;

(41) (4) Assembling the ring cable 4 on the ground, connecting the ring cable 4 to inner ends of the suspension cable 1 and the valley cable 3 via a first ring-cable-clamp anchor node 10, and connecting the ring cable 4 to inner end of the ridge cable 2 via a second ring-cable-clamp anchor node 11;

(42) (5) Pulling the outer end of the suspension cable 1 to a position distanced from a corresponding connection anchor node of the top ring beam or truss and the peripheral steel structure 7, by a predetermined distance within 0.4 m to 1.5 m by means of an auxiliary cable, so as to lift the ring cable 4 together with the ridge cable 2 and the valley cable 3 off the ground;

(43) (6) Replacing a traction assembly with a tension assembly, and synchronously tensioning the outer end of the suspension cable 1 based on the result of the construction stimulation analysis, detecting the tension stress 6.sub.DS on the tensioned suspension cable 1, and determining whether the tension stress 6.sub.DS satisfies a suspension-cable-tension-stress determination condition for allowing construction:
0.956.sub.D06.sub.DS1.056.sub.D0, wherein

(44) 6.sub.D0 is a pre-tension stress of suspension cable determined by the whole-process computer simulation analysis,

(45) if not, it needs to adjust the tension stress of the suspension cable 1 by loosening or tightening the tensioned suspension cable until the determination condition is satisfied,

(46) after the outer end of the suspension cable 1 is tensioned in place, the outer end of the suspension cable 1 is connected to the ring beam or truss-suspension cable anchor node at the top 6.

(47) (7) Pulling the outer end of the ridge cable 2 to a position adjacent to a corresponding ring beam-ridge cable anchor node 8 at the middle layer by means of the auxiliary cable, then replacing a traction assembly with a tension assembly, and synchronously tensioning the outer end of the ridge cable 2 based on the result of the construction stimulation analysis, detecting the tension stress 6.sub.JS of the tensioned ridge cable 2, and determining whether the tension stress 6.sub.JS satisfies a ridge-cable-tension-stress determination condition for allowing construction:
0.956.sub.J06.sub.JS1.056.sub.J0, wherein

(48) 6.sub.J0 is a pre-tension stress of ridge cable determined by the whole-process computer simulation analysis,

(49) if not, it needs to adjust the tension stress of the ridge cable 2 by loosening or tightening the tensioned ridge cable until the determination condition is satisfied,

(50) after the outer end of the ridge cable 2 is tensioned in place, the outer end of the ridge cable 2 is connected to the ring beam or truss-ridge cable anchor node 8.

(51) (8) Synchronously tensioning the outer end of the valley cable 3 based on the result of the construction stimulation analysis, detecting the tension stress 6.sub.GS of the tensioned valley cable 3, and determining whether the tension stress 6.sub.GS satisfies a valley-cable-tension-stress determination condition for allowing construction:
0.956.sub.G06.sub.GS1.056.sub.G0, wherein

(52) 6.sub.G0 is a pre-tension stress of valley cable determined by the whole-process computer simulation analysis,

(53) if not, it needs to adjust the tension stress of the valley cable 3 by loosening or tightening the tensioned valley cable 3 until the determination condition is satisfied,

(54) after the outer end of the valley cable 3 is tensioned in place, the outer end of the valley cable 3 is connected to the ring beam or truss-valley cable anchor node 9.

(55) (9) Detecting the maximum deformation value d.sub.S of the ring cable 4, and determining whether the maximum deformation value d.sub.S satisfies a ring-cable-deformation determination condition for allowing construction:
0.90 d.sub.0d.sub.S1.10 d.sub.0,wherein

(56) d.sub.0 is a maximum deformation value determined by the whole-process computer simulation analysis;

(57) detecting the tension stress 6.sub.HS of the ring cable 4, and determining whether the tension stress 6.sub.HS satisfies a ring-cable-tension-stress determination condition for allowing construction:
0.90 6.sub.H06.sub.HS1.10 6.sub.H0, wherein

(58) 6.sub.H0 is a pre-tension stress of ring cable determined by the whole-process computer simulation analysis,

(59) if not, it needs to readjust the tension stress of the suspension cable 1, the ridge cable 2 and the valley cable 3 until the ring-cable-tension-stress and ring-cable-deformation determination conditions for allowing construction, as well as the suspension-cable-tension-stress, ridge-cable-tension-stress and valley-cable-tension-stress determination conditions for allowing construction are satisfied.

(60) (10) Tensioning the coating membrane 5 among the ridge cable 2, the valley cable 3 and a membrane side cable 12 to form the cable-membrane tensegrity structure based on the result of the construction whole-process computer simulation analysis.

(61) Exemplary Embodiment 2:

(62) It will take a stadium project as an example to describe the exemplary embodiment 2.

(63) (1) Performing the whole-process computer simulation analysis of tensioning pre-stressed tension cable, by taking a structure formation meeting design requirement as a target, taking whole tension of cable-membrane structure as a basic principle for tension construction, building up a whole structure calculation model by a computer, and inputting related structure parameters;

(64) using technical parameters, such as, the pre-stress of the tension cables, a cutting length of the cables and a sequence to tension the tension cables, for the tension construction;

(65) wherein the whole-process computer simulation analysis of tensioning pre-stressed tension cable considers structural system geometrical nonlinear, adopts a large universal finite element program and uses a Newton-Raphson nonlinear iteration strategy to solve equations.

(66) (2) Mounting the peripheral steel structure 7 from bottom to top, and mounting the ring beam-valley cable anchor node 9, the ring beam-ridge cable anchor node 8, and the ring beam-suspension cable anchor node 6;

(67) (3) Obtaining cutting lengths of the respective cables based on a result of the construction simulation analysis, and accurately cutting the ring cable 4 and the radial cables 1, 2, 3 based on the obtained cutting lengths;

(68) (4) Assembling the ring cable 4 on the ground, connecting the ring cable 4 to the inner end of the suspension cable 1 via a first ring-cable-clamp anchor node 10, and connecting a second ring-cable-clamp anchor node 11 to the ring cable 4 at the same time;

(69) (5) Pulling the outer end of the suspension cable 1 to a position distanced from a corresponding connection anchor node 6 of the top ring beam or truss and the peripheral steel structure 7, by a predetermined distance within 0.4 m to 1.5 m by means of an auxiliary cable, so as to lift the ring cable 4 off the ground;

(70) (6) Connecting the first ring-cable-clamp anchor node 10 to inner end of the valley cable 3, and connecting the second ring-cable-clamp anchor node 11 to inner end of the ridge cable 2;

(71) (7) Replacing a traction assembly with a tension assembly, and synchronously tensioning the outer end of the suspension cable 1 based on the result of the construction stimulation analysis, detecting the tension stress 6.sub.DS of the tensioned suspension cable 1, and determining whether the tension stress 6.sub.DS satisfies a suspension-cable-tension-stress determination condition for allowing construction:
0.956.sub.D06.sub.DS1.056.sub.D0, wherein

(72) 6.sub.D0 is a pre-tension stress of suspension cable determined by the whole-process computer simulation analysis,

(73) if not, it needs to adjust the tension stress of the suspension cable 1 by loosening or tightening the tensioned suspension cable until the determination condition is satisfied,

(74) after the outer end of the suspension cable 1 is tensioned in place, the outer end of the suspension cable 1 is connected to the ring beam or truss-suspension cable anchor node at the top 6.

(75) (8) Pulling the outer end of the ridge cable 2 to a position adjacent to a corresponding ring beam-ridge cable anchor node 8 at the middle layer by means of the auxiliary cable, then replacing a traction assembly with a tension assembly, and synchronously tensioning the outer end of the ridge cable 2 based on the result of the construction stimulation analysis, detecting the tension stress 6.sub.JS of the tensioned ridge cable 2, and determining whether the tension stress 6.sub.JS satisfies a ridge-cable-tension-stress determination condition for allowing construction:
0.956.sub.J06.sub.JS1.056.sub.J0, wherein

(76) 6.sub.J0 is a pre-tension stress of ridge cable determined by the whole-process computer simulation analysis,

(77) if not, it needs to adjust the tension stress of the ridge cable 2 by loosening or tightening the tensioned ridge cable until the determination condition is satisfied,

(78) after the outer end of the ridge cable 2 is tensioned in place, the outer end of the ridge cable 2 is connected to the ring beam or truss-ridge cable anchor node 8.

(79) (9) Pulling the outer end of the valley cable 3 to be adjacent to a corresponding ring beam or truss-valley anchor node 9 by means of an auxiliary cable, replacing a traction assembly with a tension assembly, and synchronously tensioning the outer end of the valley cable 3 based on the result of the construction stimulation analysis, detecting the tension stress 6.sub.GS on the tensioned valley cable 3, and determining whether the tension stress 6.sub.GS satisfies a valley-cable-tension-stress determination condition for allowing construction:
0.956.sub.G06.sub.GS1.056.sub.G0, wherein

(80) 6.sub.G0 is a pre-tension stress of valley cable determined by the whole-process computer simulation analysis,

(81) if not, it needs to adjust the tension stress of the valley cable 3 by loosening or tightening the tensioned valley cable 3 until the determination condition is satisfied,

(82) after the outer end of the valley cable 3 is tensioned in place, the outer end of the valley cable 3 is connected to the ring beam or truss-valley cable anchor node 9.

(83) (10) Detecting the maximum deformation value d.sub.S of the ring cable 4, and determining whether the maximum deformation value d.sub.S satisfies a ring-cable-deformation determination condition for allowing construction:
0.90 d.sub.0d.sub.S1.10 d.sub.0, wherein

(84) d.sub.0 is a maximum deformation value determined by the whole-process computer simulation analysis;

(85) detecting the tension stress 6.sub.HS of the ring cable 4, and determining whether the tension stress 6.sub.HS satisfies a ring-cable-tension-stress determination condition for allowing construction:
0.90 6.sub.H06.sub.HS1.10 6.sub.H0, wherein

(86) 6.sub.H0 is a pre-tension stress of ring cable determined by the whole-process computer simulation analysis,

(87) if not, it needs to readjust the tension stress of the suspension cable 1, the ridge cable 2 and the valley cable 3 until the ring-cable-tension-stress and ring-cable-deformation determination conditions for allowing construction, as well as the suspension-cable-tension-stress, ridge-cable-tension-stress and valley-cable-tension-stress determination conditions for allowing construction are satisfied.

(88) (11) Tensioning the coating membrane 5 between the ridge cable 2, the valley cable 3 and a membrane side cable 12 to form the cable-membrane tensegrity structure based on the result of the construction whole-process computer simulation analysis.

(89) Hereafter, it will describe a multi-stage design method, based on bearing whole-process, of a pre-stress tensegrity structure of an opening type with reference to FIGS. 1-17.

(90) An opening-type whole tension roof structure, as shown in FIG. 1, has a maximum cantilever length of 43 m and a maximum height of 65 m. The whole roof structure system is formed by a radial suspension cable 1, a membrane structure ridge cable 2 and a valley cable 3, a membrane side cable 12, a ring cable 4 and a peripheral supporting structure 7.

(91) Step 1:

(92) According to the relevant national design standard, determining following parameters: cable elastic modulus E.sub.s=1.6105 MPa, (nominal) yield strength f.sub.y=1330 MPa, limit strength f.sub.u=1670 MPa, linear expansion coefficient a=1.210.sup.5/ C. ; cable clamp anchor node friction factor and cable clamp anchor node restriction rigidity calculated by performing mechanical tests on the cable and the cable clamp anchor node in a laboratory and considering about 3% loss.

(93) Based on the laboratory test results, the structure material model to is set to have the material nonlinear properties, and the structural system geometry nonlinear and the anchor node pre-stress loss are considered in the process of calculation. The analysis of the pre-stress cable-membrane tensegrity structure of an opening type is conducted by the ANSYS soft, and equations are solved by the Newton-Raphson nonlinear iteration strategy. Based on the analysis result, it can be obtained the cable pre-stress 6.sub.0=334 Mpa, determine the mechanics response stages of various structure elements, and draw the response curves of the related structure elements (see FIGS. 12-14).

(94) Step 2:

(95) Under the action of the permanent load and the one times of variable load (P.sub.1), through calculation, it can be obtained that the maximum tension stress of tension cable 6.sub.1=580 Mpa <0.41670 Mpa, the minimum tension stress of tension cable 6.sub.s=210 Mpa>0, meeting the cable material bearing capability requirement; that the ring cable vertical deformation value d.sub.1=476 mm<43000/85, meeting the requirement of allowable maximum vertical deformation value for the ring cable under the action of the permanent load and the one times of variable load (P.sub.1). Also, it can be determined that the valley cable curve angle .sub.1=6 degrees>5 degrees in a case where the valley cable vertically deforms under the action of snow load, and it can be determined that the valley cable meets the requirement of the allowable minimum curve angle value. Since the above parameters all satisfy the related safety conditions, it is suitable to set the pre-tension stress of tension cable 6.sub.0=334 Mpa, then the next step of design may be conducted.

(96) Step 3:

(97) In the stage {circle around (2)}, through analysis, it can be obtained the load incremental times P.sub.s/P.sub.1 equals 1.9 when the valley cable tension stress is decreased to the minimum, wherein K.sub.s=1.8, P.sub.s/P.sub.1>K.sub.s, thus it can be determined that the safety condition regarding elastic bearing capacity in stage {circle around (2)} is satisfied by the load incremental times P.sub.s/P.sub.1; through calculation, the ring cable vertical deformation value d.sub.s equals 1163 mm when the tension stress is decreased to the minimum, in addition, the ring cable vertical deformation value d.sub.1=476 mm under the action of the permanent load and the one times of variable load (P.sub.1), thus, it can be obtained that the elastic vertical deformation capacity coefficient d.sub.s/d.sub.1=2.44. In the step 2, when the parameter =1.2, d.sub.s/d.sub.1>(P.sub.s/P.sub.1) is satisfied. In this case, the safety condition regarding elastic vertical deformation capacity in stage {circle around (2)} is satisfied, then the next step of design may be conducted.

(98) Step 4:

(99) In the preceding stage {circle around (3)}, thought analysis, it can be obtained that the load incremental times P.sub.y/P.sub.1 equals 8.2 when the tension cable is yielded, wherein when K.sub.y=6.5, P.sub.y/P.sub.1>K.sub.y, thus, it can be determined that the safety condition regarding system yield bearing capacity in stage {circle around (3)} is satisfied by the load incremental times P.sub.y/P.sub.1; through calculation, it can be obtained that the ring cable vertical deformation value d.sub.y equals 2863 mm when the tension cable is yielded, and when [d.sub.y]=L/15=2867 mm, d.sub.y<[d.sub.y], and further, .sub.y=1.2 degrees>0. thus, it can be determined that the safety condition regarding system yield vertical deformation capacity in stage is satisfied, then the next step of design may be conducted.

(100) Step 5:

(101) In the stage {circle around (4)}, thought analysis, it can be obtained that the load incremental times P.sub.u/P.sub.y equals 1.85 corresponding to the tension cable limit breaking, wherein when K.sub.u=1.8, P.sub.u/P.sub.y>K.sub.u, thus, it can be determined that the safety condition regarding system limit bearing capacity in stage {circle around (4)} is satisfied by the load incremental times P.sub.u/P.sub.y; thought calculation, it can be obtained that the ring cable vertical deformation value d.sub.u corresponding to the tension cable limit breaking equals 6568 mm, thus, the system vertical deformation capacity ductility coefficient d.sub.u/d.sub.y equals 2.45, wherein when =1.2, d.sub.u/d.sub.y(P.sub.u/P.sub.y), then it can be determined that the safety condition regarding system limit vertical deformation capacity in stage {circle around (4)} is satisfied by the system vertical deformation capacity ductility coefficient d.sub.u/d.sub.y.

(102) Since all safety conditions are satisfied in the above steps, the design is completed.

(103) Although several exemplary embodiments have been shown and described, it would be appreciated by those skilled in the art that various changes or modifications may be made in these embodiments without departing from the principles and spirit of the disclosure, the scope of which is defined in the claims and their equivalents.