CN102002901B - Intersection space design method based on complexity control - Google Patents

Abstract

The invention discloses an intersection space design method based on complexity control, which comprises the following steps: (1) collecting basic data; (2) designing the intersection space, wherein an initial design scheme is generated according to the existing traffic factor design method; (3) calculating and evaluating the complexity, wherein the collision probability of collision points, the complexity of the collision points and the complexity of the intersection in the initial design scheme are calculated; the complexity of the collision points and the complexity of the intersection are analyzed so as to judge whether the complexities are in conformity with the conditions or not; the step (2) is performed again if the complexities are not in conformity with the conditions, and the next step is carried out if the complexities is in conformity with the conditions; (4) evaluating the scheme, wherein the service level of the intersection is judged so as to determine whether the service level is in conformity with the requirements on the service level or not by calculating the delay of the intersection; the step (2) is carried out if the service level is not in conformity with the requirements on the service level; and (5) generating the intersection space design scheme if the scheme evaluation is in conformity with the requirements. In the method of the invention, a new intersection space design method is provided for guiding the intersection space design in the whole by utilizing the comprehensive index and enhancing the safety and the efficiency of the intersection, and the method is more scientific and reasonable.

Description

Intersection space design method based on complexity control

Technical field

The invention belongs to the traffic design field, be specifically related to a kind of method of utilizing complexity that the intersection is designed.

Background technology

Level-crossing is the bottleneck of urban highway traffic, and mixed traffic flow is the basic characteristics of China's urban traffic, and difference turns to, different types of traffic flow interweaves, intersects in the intersection, makes that the operation conditions of intersection is very complicated.

The intersection spatial design is one of important content of intersection design, is according to certain being provided with according in the functional areas, intersection autos only space, bicycle passage space, walk space being designed.

Intersection spatial design in the past is primarily aimed at the method for designing of a certain concrete design considerations; Be provided with according to carrying out part research or carrying out the intersection spatial design from an angle; Make that intersection spatial design Total tune property and directiveness are not enough, lack the spatial design that a comprehensive index instructs the intersection on the whole.

Summary of the invention

Goal of the invention: the objective of the invention is to deficiency, propose a kind of intersection space design method that improves intersection safety, efficient based on complexity control to the space design method existence of existing intersection.

Technical scheme: the intersection space design method based on complexity control of the present invention comprises the steps:

(1) basic data is collected: confirm the intersection pattern and the traffic volume through analyzing with intersection category of intersection roads and intersection surrounding enviroment.

Divide two kinds of situation:

First kind of situation: for the planning intersection, basic data is collected and is referred to confirm all kinds of design traffic volumes in this intersection according to category of intersection roads and intersection surrounding enviroment.

Second kind of situation:,, obtain the intersection road conditions, motor vehicle, bicycle, pedestrian traffic amount, signal controlling scheme through site investigation for transforming the intersection.

(2) intersection spatial design:, generate preliminary project according to existing traffic factor designing method intersection motor vehicle, bicycle, walk space.

Specifically comprise the steps:

(21), confirm initialize signal phase place scheme according to category of intersection roads and design traffic volume;

(22) functional areas, intersection are confirmed: confirm the scope of design of intersection, i.e. intersection turnover stomatodeum broadening original position is with interior whole zone;

(23) cross section, intersection resource is distributed: confirm motor vehicle, bicycle and pedestrian's passage space and take runway wide;

(24) autos only spatial design: confirm motor vehicle number of lanes, lane function; If exclusive left-turn lane is set, confirm the form that is provided with, left turn lane width, left turn lane braking section length, the memory length of left turn lane, the setting of left-hand rotation Accreditation Waiting Area, the setting of left-hand rotation channelizing line of left turn lane; If exclusive right-turn lane is set, confirm the form that is provided with, track length, turning radius, kerb radius, the podium setting of exclusive right-turn lane;

(25) bicycle passage space design: confirm the stop line for non-motor vehicles position; Confirm that left-turn non-motor crosses the street mode; Confirm right-hand rotation bicycle processing mode;

(26) walk spatial design: confirm pedestrian's street crossing mode and pedestrian island setting.

(3) complexity is calculated and is estimated: according to intersection traffic, signal, flow condition; Calculate the complexity of conflict point collision probability and conflict point complexity and intersection in the preliminary project, and whether analysis conflict point complexity and intersection complexity be eligible; If meet and then do not return step (two), meet and then get into next step.

Specifically comprise the steps:

(31) number N of statistics intersection intramural conflict point, each conflict point has three parameters: conflict point type, the preferentially magnitude of traffic flow, the secondary magnitude of traffic flow, be designated as i (k, Q, Q);

(32) type of i conflict point of judgement; The type of conflict point has five types: interflow conflict point, diverging conflicts, intersection conflict point, motor vehicle and bicycle conflict point, motor vehicle and Pedestrian conflicts's point;

(33) according to the type of i conflict point, the stream flow one that will conflict, conflict stream flow two are updated to corresponding conflict point collision probability p computation model, multiply by corresponding weight coefficient again and calculate i conflict point complexity p '.

Concrete design formulas is following:

1. intersect the conflict point collision probability:

$p=1-e^{1(1.588*{10}^{-8}{Q_1}^2+2.526*{10}^{-5}{Q}_1)Q_2}$

Wherein, p-conflict point collision probability;

Q ₁-preferential traffic flow flow (pcu/h);

Q ₂-secondary traffic flow flow (pcu/h).

2. collaborate the conflict point collision probability:

$p=0.55(1-e^{1(1.588*{10}^{-8}{Q_1}^2+2.526*{10}^{-5}{Q}_1)Q_2}),$

Wherein, p, Q ₁, Q ₂Meaning is the same.

3. diverging conflicts collision probability:

$p=0.33(1-e^{1(1.588*{10}^{-8}{Q_1}^2+2.526*{10}^{-5}{Q}_1)Q_2}),$

Wherein, p, Q ₁, Q ₂Meaning is the same.

4. motor vehicle-bicycle conflict point collision probability:

$p=1-e^{-\frac{Q_1}{60}*(-0.2{Q_2}^3+0.7{Q_2}^2-0.7Q_2+1.2)},$

Wherein, p-conflict point collision probability;

Q ₁-preferential the magnitude of traffic flow, i.e. automobile traffic flow (pcu/min);

Q ₂-secondary the magnitude of traffic flow, promptly the bicycle magnitude of traffic flow (/min).

5. motor vehicle-Pedestrian conflicts puts collision probability:

$p=1-e^{-\frac{Q_1}{60}*(-0.003{Q_2}^3+0.025Q_3+0.595)}$

P-conflict point collision probability;

Q ₁-preferential the magnitude of traffic flow, i.e. automobile traffic flow (pcu/min);

Q ₃-secondary the magnitude of traffic flow, i.e. pedestrian's magnitude of traffic flow (people/m/min).

(34) judge whether that all conflict point collision probabilities all calculate and finish, judge promptly whether i equals N, is then to continue next step, otherwise return step (32), calculate i+1 conflict point collision probability;

(35) calculate conflict point complexity and intersection complexity: each conflict point collision probability multiply by different weights, obtain conflict point complexity p ', add and solve intersection complexity C, design formulas is following:

p′ _i＝k _jp _i

$C=\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{p}_i^{\′}$

Wherein, k _j, j=1,2,3, machine representation motor-car and motor vehicle conflict respectively, motor vehicle and bicycle conflict, motor vehicle and Pedestrian conflicts, dissimilar conflict point weight coefficients are seen table 1.

The dissimilar conflict point weight coefficients of table 1

The conflict type	k 1	k 2	k 3
				Weight	1	1.3	1.7

Intersection complexity C to calculating analyzes, with C and reasonable complexity scope C ₀(as shown in table 2) compares, and whether estimate the corresponding intersection space layout scheme of this complexity value reasonable; Whether each conflict point complexity p ', it is balanced to estimate the traffic flow conflict if being analyzed; If through analyzing and diagnosing existing space layout existing problems, then return step (two) and design again, then get into next step if meet the requirements.

The reasonable complexity scope of table 2 typical intersection

1. if C＜C ₀, then the intersection complexity gets into next step and carries out evaluate alternatives within reasonable complexity scope.

2. if C＞C ₀, then the intersection complexity is excessive, and the intersection security performance can not ensure, and inefficiency should be returned step (two) design scheme is adjusted.

3. as if p '＞0.25, then this conflict point conflict situations is serious, should adjust control.

(4) evaluate alternatives: through calculating intersection delay, judge whether the intersection service level satisfies the service level requirement, then do not return step (two) if meet.

Wherein, motor vehicle is incured loss through delay the following formula calculating of employing:

1. each track is incured loss through delay and can be estimated by following formula:

d＝d ₁+d ₂+d ₃

In the formula: each track per car of d-is on average believed control delay (s/pcu);

Each track per car of d1-is on average believed control delay (s/pcu);

Additional at random incur loss through delay (s/pcu) of d2-, promptly vehicle arrives at random and causes the additional delay that the over-saturation cycle is produced;

Additional incur loss through delay (s/pcu) of the initial queuing of d3-, promptly incur loss through delay analyze initial stop having on a period stay the additional delay that the initial queuing of cumulative vehicle stands follow-up vehicle.

D1 is calculated as follows:

$d_1=d_s\frac{t_u}{T}+f_a{d}_u\frac{T-t_u}{T}$

In the formula: the saturated delay of ds-;

d _s＝0.5C(1-λ)

d _u-unsaturation is incured loss through delay;

$d_u=0.5C\frac{{(1-\mathrm{\λ})}^2}{1-\min [1,X]\mathrm{\λ}}$

C-cycle duration (s);

λ-split, the ratio of traffic flow effective green time and cycle duration;

The X-saturation ratio;

T-analyzes period lasting duration (h);

t _u-the duration of cumulative vehicle (h) in T;

$t_u=\min [T,\frac{Q_b}{C_p[1-\min [1,X\left]\right]}]$

Q _b-analyzing initial beginning cumulative vehicle (pcu), must survey;

C _pThe traffic capacity (pcu/h) in-track of calculating;

f _a-green light the phase, the wagon flow arrival rate was than positive coefficient;

$f_a=\frac{1-P}{1-\mathrm{\λ}}$

The P-green light phase arrives the ratio that vehicle accounts for arrival complete cycle amount, but field observation.

d ₂Be calculated as follows:

$d_2=900[(X-1)+\sqrt{{(X-1)}^2+T\frac{8\mathrm{eX}}{C_p}}]$

In the formula: e-single crossing signal controlling type correction coefficient, timing signal is got e=0.5; Induced signal e becomes during with saturation ratio and green light for a long time, and the average e value of advising when being 2～5s for a long time during green light is listed among the table 3-4 [40];

Other symbolic significance is the same.

Table 3 single crossing signal controlling type correction coefficient recommended value

Saturation ratio X	e	The average of e
			≤0.5	0.04～0.23	0.13
0.6	0.13～0.28	0.20
			0.7	0.22～0.34	0.28
0.8	0.32～0.39	0.35
			0.9	0.41～0.45	0.43
＞1.0	0.5	0.5

d ₃Calculate in T the cumulative vehicle duration tu and decide, specifically be calculated as follows:

2. the average letter control of each entrance driveway is incured loss through delay

Weighted average by incur loss through delay in each track in this entrance driveway is estimated:

$d_A=\underset{i}{\mathrm{\Σ}}{d}_i{q}_i/\underset{i}{\mathrm{\Σ}}{q}_i$

In the formula: d _A(s/pcu) incured loss through delay in the average letter control of-entrance driveway A;

d _i(s/pcu) incured loss through delay in the average letter control in i track among the-entrance driveway A;

q _iThe hourly traffic volume in i track is scaled the wherein traffic flow rate of peak 15min among the-entrance driveway A.

3. the control of the average signal of whole intersection is incured loss through delay

The weighted number estimation that each entrance driveway of this intersection is incured loss through delay:

$d_1=\underset{A}{\mathrm{\Σ}}{d}_A{q}_A/\underset{A}{\mathrm{\Σ}}{q}_A$

In the formula: d ₁(s/pcu) incured loss through delay in the average letter control of-intersection per car;

q _AThe peak 15min traffic flow rate of-entrance driveway A.

Bicycle is incured loss through delay the following formula of employing and is calculated:

$d_b=\frac{0.5\·C\·{(1-\frac{g_b}{C})}^2}{1-[\frac{g_b}{C}\·\min (\frac{V_b}{{C_p}^b},1.0)]}$

In the formula, d _b-bicycle is incured loss through delay (s);

C-signal period duration;

g _b-bicycle phase place green light duration;

V _b-bicycle flow rate;

C _p ^b-bicycle import the traffic capacity.

The pedestrian incurs loss through delay the following formula of employing and calculates:

$d_p=\frac{{(C-g)}^2}{2C}$

In the formula, d _p-pedestrian incurs loss through delay (s);

C-Cycle Length (s);

G-pedestrian's effective green time (s).

(5) meet the demands when the complexity evaluation, service level meets the demands, and then generates intersection spatial design scheme.

Above-mentioned steps is applicable to the planning intersection, and for transforming the intersection, then skips steps (two) directly gets into step (three) earlier, and promptly complexity is calculated and estimated, and then returns step (two) again and carries out the space layout design.

The present invention compared with prior art; Its beneficial effect is: 1, the present invention proposes a composite target and comes on the whole the intersection spatial design to be instructed; Improve safety, the efficient of intersection, the present invention proposes the new intersection space design method of a cover, and is more scientific and reasonable; 2, the inventive method has been simplified intersection spatial design process; Do not need frequently to calculate the evaluation index such as the traffic capacity, delay, queue length of intersection; Only need according to the relation between intersection space layout and the complexity; Through simple estimation, can predict the influence of the change of space layout, thereby improve the operating efficiency of intersection spatial design the intersection running status.

Description of drawings

Fig. 1 is a method for designing flow chart of the present invention.

Fig. 2 collects sketch map for basic data.

Fig. 3 is an intersection space layout design flow diagram.

Fig. 4 is the complexity calculating method sketch map.

Fig. 5 is a complexity evaluation method sketch map.

Fig. 6 estimates sketch map for the intersection.

Fig. 7 transforms the path space design of preceding intersection among the embodiment.

Fig. 8 is the river road-road intersection signal timing (unit: s) of the institution of higher learning of offering incense in a temple among the embodiment.

Fig. 9 transforms the path space design of intersection, back among the embodiment.

Figure 10 is the timing figure (unit: s) of middle scheme one among the embodiment.

The specific embodiment

Be example with Nanjing river road-intersection, the institution of higher learning road spatial design of offering incense in a temple below, technical scheme of the present invention is elaborated, but protection scope of the present invention be not limited to said embodiment.

Concrete design procedure is following:

(1) the intersection basic data is collected

River road-the intersection, institution of higher learning road of offering incense in a temple is positioned at the central area, Nanjing, is intersected by the river road of offering incense in a temple in transmeridional institution of higher learning road and north-south to form.

1. intersection road conditions

The space layout of this intersection and geometric properties thereof such as table 4 are with shown in Figure 7.

Table 4 river road-intersection, the institution of higher learning road present situation geometrical condition summary sheet of offering incense in a temple

Annotate: 1.L, T, R, TL, TR, TLR represent left-hand rotation, craspedodrome, right-hand rotation, a straight left side, straight right, straight track, the left and right sides respectively; 2. entrance driveway and exit width are with road-center alignment arranged on both sides.

2. intersection signal controlled condition

The control of two phase signal lamp is adopted in this intersection, and the signal phase design is as shown in Figure 8:

Annotate: 1, there is walker signal lamp this intersection, nothing but motor vehicle signal lamp; 2,7:00～11:00 signal timing dial is identical.

3. intersection flow condition

This intersection is bigger at the traffic volume of peak period, especially goes to school period and evening peak classes are over the period in morning peak.The control time of intersection is 7:00～11:00 in the morning on working day, and the investigating period weather condition is good.

Through Video Document is carried out statistical analysis, can obtain automobile traffic amount (table 5), the bicycle traffic volume (table 6) and the pedestrian traffic amount (table 7) of this intersection peak hour.Wherein motor vehicle has been converted into the standard passenger car equivalence with in-between car and large car.

Table 5 each the import track automobile traffic amount of river road-intersection, institution of higher learning road of offering incense in a temple

Table 6 each the import bicycle traffic volume of river road-intersection, institution of higher learning road of offering incense in a temple

Table 7 each the import cross walk pedestrian traffic amount of river road-intersection, institution of higher learning road of offering incense in a temple

Present embodiment belongs to transforms the intersection, directly gets into former step (three) earlier, and promptly complexity is calculated and estimated, and then returns former step (two) and carry out the space layout design.

(3) complexity is calculated and is estimated

1. this intersection conflict point calculates

Through statistics, can obtain the number of conflict between the different modes of transportation, as shown in table 8:

The dissimilar numbers of conflict of table 8

2. the intersection complexity is calculated

Get the magnitude of traffic flow according to inquiry agency, the magnitude of traffic flow be assigned on each conflict point according to streamline, calculate the collision probability of each conflict point of intersection:

(1) motor vehicle-motor vehicle conflict

Intersect conflict: first phase place for example, western import is kept straight on and is turned left to take place to intersect to conflict with eastern import, and the traffic volume is respectively 175pcu/h and 69pcu/h, with its substitution formula:

$p_{a-a,j}=1-e^{(1.588\×{10}^{-8}{Q_1}^2+2.526\×{10}^{-5}{Q}_1)Q_2}=1-e^{(1.588\×{10}^{-8}\×{175}^2+2.526\×{10}^{-5}\×175)\×69}=0.2872$

Interflow conflict: first phase place for example, western import craspedodrome and southing mouth are turned right and the interflow takes place are conflicted, and the traffic volume is respectively 175pcu/h, 148pcu/h, with its substitution formula:

$p_{a-a,m}=0.55[1-e^{(1.588\×{10}^{-8}{Q_1}^2+2.526\×{10}^{-5}{Q}_1)Q_2}]=0.55\×[1-e^{(1.588\×{10}^{-8}\×{175}^2+2.526\×{10}^{-5}\×175)\×148}]=0.2581$

Shunting conflict: first phase place for example, eastern import is kept straight on and is turned left to take place the shunting conflict, and the traffic volume is respectively 172pcu/h, 69pcu/h, with its substitution formula:

$p_{a-a,d}=0.33\×[1-e^{(1.588\×{10}^{-8}{Q_1}^2+2.526\×{10}^{-5}{Q}_1)Q_2}]=0.33\×[1-e^{(1.588\×10^{-8}\×{172}^2+2.526\×{10}^{-5}\×172)\×69}]=0.1413$

Result of calculation sees table 9 for details.

Table 9 motor vehicle-motor vehicle conflict point complexity result of calculation

(2) motor vehicle-bicycle conflict

The substitution computes, first phase place for example, eastern import craspedodrome motor vehicle and the non-conflict of eastern import left-turn non-motor generator, the traffic volume is respectively 172pcu/h, and 11/h, with its substitution formula:

$p=1-e^{-\frac{Q_1}{60}(-0.2{Q_2}^3+0.7{Q_2}^2-0.7Q_2+1.2)}=1-e^{-\frac{172/60}{60}\×[-0.2\×{\left(\frac{11}{60}\right)}^3+0.7\×{\left(\frac{11}{60}\right)}^2-0.7\×\frac{11}{60}+1.2]}=0.0509$

Result of calculation sees table 10 for details.

Table 10 motor vehicle-bicycle conflict point complexity result of calculation

(3) motor vehicle-Pedestrian conflicts

According to the actual conditions of intersection, select the substitution computes.For example: first phase place, eastern import left-hand rotation and southing mouth pedestrian generator people conflict, the traffic volume is respectively 72pcu/h, 1047 people/h, the current condition in intersection is good, so:

$p=1-e^{-\frac{Q_1}{60}(0.003{Q_3}^2-0.025Q_3+0.595)}=1-e^{-\frac{72/60}{60}\×[0.003\×{\left(\frac{1047}{60}\right)}^2-0.025\×\frac{1047}{60}+0.595]}=0.1212$

Result of calculation sees table 11 for details.

Table 11 motor vehicle-Pedestrian conflicts puts complexity result of calculation

Result of calculation gathers as shown in table 12:

Table 12 present situation complexity result of calculation

The complexity size of this intersection is 8.45.

3. the intersection complexity is estimated

Xianghe-intersection, institution of higher learning road belongs to the intersection that subsidiary road and branch road intersect, and East and West direction institution of higher learning road is a branch road, and eastern import has an import track, and western import has two import tracks, and the river road of offering incense in a temple, north-south is a subsidiary road, and three entrance driveway are respectively arranged.Function collecting and distributing and service is taken into account in this intersection.The reasonable complexity scope in such intersection is≤10.6, this shows that present intersection complexity is within reasonable complexity scope.But, can find out that there is certain problem at present in this intersection from above computational process and result:

This intersection first phase place complexity is that 2.82, the second phase place complexities are that 5.63, the second phase place complexities are much larger than the first phase place complexity.This is that the complexity of each conflict point is bigger because the second phase place intersection intramural conflict is counted out morely.In addition, the complexity proportion that the machine in second phase place-the machine conflict is produced is the highest.Find that through analyzing 10 maximum conflict points of this intersection complexity almost are the machine-machine conflict point from second phase place (being the north and south phase place) all.The conflict point complexity is greater than 0.25 have 10, and is as follows:

The big conflict point of table 13 complexity

Can find out by last table, craspedodrome motor vehicle and serious to the conflict of turning left between the favourable turn motor-car, wherein the conflict of north and south entrance driveway is particularly serious.Because the through-traffic stream flow of this intersection North and South direction is bigger, it is less that the subtend left-turn traffic flow finds suitable gap to pass through the chance of conflict point during green light.Though through-traffic stream is higher than left-turn traffic flow through the priority of intersection; But in the running of reality; In case have suitable gap to make to win a left-hand rotation autos only; The left-hand rotation motor vehicle of back queuing will follow first left-hand rotation motor vehicle closely continuously through conflict point, forces the craspedodrome wagon flow of conflict with it to be interrupted, and through-traffic stream is caused obstruction.Therefore, should take measures necessary to reduce the conflict vehicle flowrate at straight left conflict point place, north-south,, guarantee that left turning vehicle can find suitable critical gap, reduce the interference of left-turn traffic flow through-traffic stream to reduce the probability of straight left side conflict.

Through analytical engine-non-complexity of conflicting; The machine that left-turn non-motor produced-non-number of conflict is maximum; And its complexity also is maximum, therefore should take certain measure to reduce number of conflict between left-turn non-motor and the motor vehicle and the probability that clashes.

Because machine-people's number of conflict is less, and this intersection size is less, the pedestrian can seek suitable gap through the intersection in green time, and this intersection machine-people's running status is good.

Return step (two), carry out intersection space layout design

At first consider to start with from lane function division, consideration is widened original shared track and is dedicated Lanes, and to eliminate the shunting conflict in the shared track: the straight left-lane that the southing stomatodeum is original transform the left-hand rotation dedicated Lanes as; The straight right lane of northing mouth transform the right-hand rotation dedicated Lanes as, and straight left-lane transform the craspedodrome dedicated Lanes as.Concrete transformation is as shown in Figure 9.

Get into step (three) again and carry out complexity calculating and evaluation:

The traffic volume is assigned to each conflict point, selects suitable design formulas substitution computation complexity, computational methods are the same, and calculating the intersection complexity is 6.56

The complexity of this intersection is 6.56 after the transformation, less than the complexity before transforming.Can think the intersection spatial design to be transformed and obtain good effect through complexity control.But can find that through analyzing the complexity between north-south craspedodrome and the left-hand rotation motor vehicle is still very big, and is visible, though divide the number that has reduced conflict point through adjustment motorway function, the situation that the conflict point complexity is big does not improve.Find that through further analysis under current flux and phase condition, the adjustment of space layout has been difficult to solve the bigger problem of intersection complexity, need seek the cooperation of time resource.North-south left-hand rotation motor vehicle flow is respectively 252pcu/h, 73pcu/h, and wherein southing mouth left-hand rotation motor vehicle flow is bigger.Though the north and south import is provided with the left-hand rotation dedicated Lanes; But owing to be not provided with the protection phase place; The function of left-hand rotation dedicated Lanes is not fully exerted, and the conflict between left turn traffic and the craspedodrome wagon flow still exists, and has had influence on whole intersection operational efficiency.Initial scheme is carried out scheme to be designed again.Initial scheme is carried out scheme design again, consider to add the protection phase place of turning left,, be designated as middle scheme one with the left-hand rotation of elimination north and south entrance driveway and conflicting of subtend craspedodrome wagon flow.

Return step (two) again and carry out intersection space layout design: middle scheme one intersection signal phase place is shown in figure 10.

Get into step (three) again and carry out complexity calculating and evaluation: according to project setting, flow is redistributed calculating, the intersection complexity in the middle of can obtaining in the scheme one is 4.61.Intersection intramural conflict point complexity is relatively more balanced, has solved the serious problem of north-south automobile traffic conflict basically, and has reduced the complexity between left-turn non-motor and the motor vehicle.

(4) evaluate alternatives

It is as follows to transform each entrance driveway operation conditions of intersection, back:

Intersection capacity and service level in the middle scheme one of table 14

Can find out that from last table though eastern import service level is relatively poor, whole intersection running status is good, satisfies C level service level.

(5) generation scheme

For transforming the intersection, target be make this intersection intramural conflict count out minimizings, complexity reduces and be tending towards equilibrium, and guarantees that whole intersection service level is not less than the C level.The function of considering this intersection is to take into account collecting and distributing and service, and main service object lays equal stress on for automobile traffic and slow-moving traffic, thus get complexity minimum and the satisfactory scheme of service level, to guarantee intersection user's safety to greatest extent.Scheme one is optimal case in the middle of getting, and its spatial design layout is as shown in Figure 9.

As stated, although represented and explained the present invention that with reference to specific preferred embodiment it shall not be construed as the restriction to the present invention self.Under the spirit and scope of the present invention prerequisite that does not break away from the accompanying claims definition, can make various variations in form with on the details to it.

Claims (2)

1. the intersection space design method based on complexity control is characterized in that comprising the steps:

(1) basic data is collected;

(2) intersection spatial design:, generate preliminary project according to existing traffic factor designing method intersection motor vehicle, bicycle, walk space;

(3) complexity is calculated and is estimated: according to intersection traffic, signal, flow condition, calculate conflict point collision probability, conflict point complexity and intersection complexity in the preliminary project, and analyze conflict point and the intersection complexity whether eligible; If meet and then do not return step (two), meet and then get into next step;

Step (three) specifically comprise the steps:

(31) number

of statistics intersection intramural conflict point; Each conflict point has three parameters: conflict point type, the preferential magnitude of traffic flow, the secondary magnitude of traffic flow are designated as

;

(32) type of judgement

individual conflict point;

(33) according to the type of individual conflict point; The preferential magnitude of traffic flow, the secondary magnitude of traffic flow are updated to corresponding conflict point complexity computation model, calculate

individual conflict point collision probability

;

(34) judging whether that all conflict point collision probabilities all calculate finishes; Promptly judge

and whether equal

; Be then to continue next step; Otherwise return step (32), calculate

individual conflict point collision probability;

(35) calculate the intersection complexity: all conflict point collision probabilities multiply by different weights; Obtain each conflict point complexity

, again all conflict point complexities are added and solve intersection complexity

; Intersection complexity

to calculating is analyzed; Whether

, it is reasonable to estimate the corresponding intersection space layout scheme of this complexity value if being compared with reasonable complexity scope

; analyzes to each conflict point complexity, and whether estimate the traffic flow conflict balanced; If through analyzing and diagnosing existing space layout existing problems, then return step (two) and design again, then get into next step if meet the requirements;

(4) evaluate alternatives: through calculating intersection delay, judge whether the intersection service level satisfies the service level requirement, then do not return step (two) if meet;

(5) evaluate alternatives meets the requirements and then generates intersection spatial design scheme.

2. the intersection space design method based on complexity control according to claim 1, it is characterized in that: step (two) specifically comprise the steps:

(21), confirm initialize signal phase place scheme according to category of intersection roads and design traffic volume;

(22) functional areas, intersection are confirmed: confirm the scope of design of intersection, i.e. intersection turnover stomatodeum broadening original position is with interior whole zone;

(23) cross section, intersection resource is distributed: confirm motor vehicle, bicycle and pedestrian's passage space and take runway wide;

(24) autos only spatial design: confirm motor vehicle number of lanes, lane function; Confirm the form that is provided with, left turn lane width, left turn lane braking section length, the memory length of left turn lane, the setting of left-hand rotation Accreditation Waiting Area, the setting of left-hand rotation channelizing line of left turn lane; Confirm the form that is provided with, track length, turning radius, kerb radius, the podium setting of exclusive right-turn lane;

(25) bicycle passage space design: confirm the stop line for non-motor vehicles position; Confirm that left-turn non-motor crosses the street mode; Confirm right-hand rotation bicycle processing mode;

(26) walk spatial design: confirm pedestrian's street crossing mode and pedestrian island setting.

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