首页 朱明之关于建筑-公众号 笔记《模块化背景下的塔式起重机市场》



原文标题《Underthe PPVC: tower cranes》

By Heinz-GertKessel, Alex Dahm13 July 2020

PPVC (prefabricated pre-finished volumetricconstruction) is becoming increasingly popular. It requires high capacity towercranes

Potain MR608

Hotel and student apartment towers areideal for modular construction, here carried out by a Potain MR608 with a 32tonne lifting capacity up to 22.5 metres radius

酒店和学生公寓大楼是模块化建筑的理想选择,这里由Potain MR608进行,具有32吨的起重能力,半径达22.5米

Prefabrication is a broad category thatrefers to a construction process where building elements are constructedoff-site and then shipped to the construction site for installation. Generally,prefabrication can be categorised as either two-dimensional building panels(2D), like walls, floor systems, or three-dimensional modules (3D). This iswhere an entire unit of a building is constructed off-site.


Fully fitted out modular units require theleast amount of on-site construction time as all plumbing, electrical, internalfinishes and fixtures have typically already been installed at the factory.This PPVC (prefabricated pre-finished volumetric construction) method increasesproductivity and sustainability of modularisation to its highest level incomparison to traditional on-site construction methods.


) Savings in constructiontime: The most obvious benefit is saving construction time. Siteestablishment, earth work and foundations can all be in progress on site at thesame time as modules are fabricated in the factory off site. A six-storeyhotel, for example, can be built on the factory floor in three months andassembled in only 20 days on site. This time saved has financial benefit, asthere is a faster return on equity as rental revenue.


) Quality assurance: Noweather-related delays affect factory-based module construction. Assembly lineproduction and robots can raise building construction into today’s industrystandard of productivity.


) Safety: More offsiteconstruction means fewer hours working at height.


) Traffic reduction: Modularconstruction can reduce the number of site deliveries by 90 percent anddecreases the average travel distance of workers to the site by 75 %.


) Overcome recruitingproblems: 80 % of the traditional labour activity can be moved offsite tothe module manufacturing facility. For this workforce the daily commute remainsunchanged from project to project while the few experts to fix the modules onsite can be offered an attractive skilled job.


) Reducing noise, dust and carbondioxide pollution on site: The construction phase on site is reduced as isthe amount of heavy equipment. Electric tower cranes for module placementminimise the noise and pollution impact on the neighbourhood and environment.


) Waste and space reduction: Modularconstruction cuts net waste in half compared to conventional construction.Modules delivered just in time under the crane hook reduce the requestedstorage area for construction material.


) Sustainability: Nearly 90 % offsite industrialised module production has great potential for green andlean construction, reducing the greenhouse gas emission during fabrication aswell as during the lifetime of a building.


Cost drivers for PPVC are:

) Module transportrestrictions: Restrictive road regulations, abnormal load transportpermits and transport restrictions on inner city sites sets economic sitelimits. Overall transport size is restricted to 3.4 metres wide, 3.2 metresheight and 12 metres length. Maximum weight is 30 to 40 tonnes. Transport is 20% of the PPVC cost drivers tending to increase.


) Crane size: Above six floorstower cranes are preferred due to the space needed for erection. Two types ofPPC module system are in general use. The weight of steel modular units isbetween 8 and 20 tonnes while concrete modular units weigh 25 to 35 tonnes.Concrete modules are often preferred in residential buildings due to durabilityand ease of inspection. Less carbon intensive module construction will see morehybrid and light timber modules because the production of cement accounts foran estimated 5 % of global carbon dioxide emission.


Adding to the module weight will bepurpose-built self-balancing lifting frames. These prevent the introduction ofinward forces into the modules and accommodate the individual centre of gravityof every module for precise positioning. For these reasons PPVC projectsrequire high capacity tower cranes. Experience in Singapore shows the initialcost and rental rates of tower cranes above 30 tonnes capacity is responsiblefor 15 % of the PPVC project total. Recent tower crane developments, however,for the PPVC market will help contractors to keep crane costs of upcomingprojects more easily under control.


Comansa LC21LC1050

Concrete module placement using a ComansaLC21LC1050 in double trolley, heavy lift configuration, for fast trackapartment construction in Singapore

混凝土模块放置使用Comansa LC21LC1050双小车,重型升降机配置,用于新加坡的快速轨道公寓建设

Same again

Projects delivering the greatest costsavings with the PPVC construction method are those with the highest level ofrepeatability. Examples include student accommodation, hotels, residentialtowers and affordable homes. These are exactly the type of building for whichdemand is rising as a result of the global trend for urbanisation.


PPVC construction can be the solution wherethere is a labour shortage, where traditional construction is expensive andwhere there Is a need to build rapidly, due to extreme housing shortages.Housing is needed in Australia, France, the UK and the USA, which recentlyannounced one million housing units to be built by 2020. Governments inAustralia, Singapore and the UK are making offsite construction a strategicpriority. Singapore’s Housing and development Board (HDB) adopted the concretePPVC method for 35 % of its projects in 2019. In Australia the government isseeking to create “twenty-minute cities”, so-called because of the traveldistance in which people can fulfil their daily needs. It will increase thenumber of high-rise residential towers to reduce the carbon footprint. Othermunicipalities around the world will follow, again boosting the market for PPVCprojects.

PPVC建筑可以解决劳动力短缺、传统建筑昂贵以及由于住房极度短缺而需要快速建造的问题。澳大利亚、法国、英国和美国都需要住房,这些国家最近宣布将在2020年前建造100万套住房。澳大利亚、新加坡和英国政府正把场外建设作为一项战略重点。2019年,新加坡住房和发展局(HDB) 35%的项目采用了具体的PPVC方法。在澳大利亚,政府正试图创建“20分钟城市”,之所以这样称呼是因为人们可以满足他们的日常需求的旅行距离。它将增加高层住宅楼的数量,以减少碳足迹。世界其他城市也将跟进,再次推动PPVC项目的市场。

Singapore is the biggest testing ground formodular construction today. Early experiments elsewhere revealed the challengefor the lifting equipment. The 12-storey Habitat 67 apartment complex built forthe Expo in Montreal, Canada, in 1967 is a manifestation of the potential ofprefabrication. The 354 concrete modules, each weighing 80 tonnes, were placedusing a Dominion Bridge rail-travelling, pedestal-mounted purpose-builtstiffleg derrick crane. It offered 82 tonnes of capacity at a radius of 30.5metres and 100 tonnes at 18.2 metres. To level the concrete modules at eachcorner of the square Francon lifting frame, an individually operated hydraulicjack was installed at the end of the lifting rope.

新加坡是当今最大的模块化建筑试验场。其他地方的早期实验揭示了起重设备的挑战。1967年,加拿大蒙特利尔为世博会建造了12层的Habitat 67公寓,展示了预制的潜力。354个混凝土模块,每个重达80吨,使用Dominion Bridge的轨道移动、底座安装专用刚性腿起重机放置。它在半径30.5米的范围内提供82吨的容量,在半径18.2米的范围内提供100吨的容量。为了使方形法兰吊架每个角落的混凝土模块水平,在吊绳的末端安装了一个独立操作的液压千斤顶。

Also in 1967, another PPVC project started,in San Antonio, Texas, where its economical design and short construction timeare notable. The 22-storey Hilton Palacio de Rio hotel was completed in just 10months. Modular construction cut this two-year job to nine months. A total of496 guest room modules were placed in 46 days using a 300 tonne Manitowoc 4000Wring crane. It had a customised 50 tonne capacity, 82 3 metre boom with cantedtop to increase usable load height. The fully fitted out 35 tonne modules,including furniture, were lifted into place within an accuracy of ¾ inch (19mm) using a purpose built load spreader with Helicoguide counterbalancing. Thisconsisted of a Sikorsky helicopter motor and 60 h.p. engine.

同样是在1967年,另一个PPVC项目在德克萨斯州的圣安东尼奥启动,其经济的设计和较短的施工时间是值得注意的。22层的希尔顿Palacio de里约热内卢酒店仅用了10个月就完工了。模块化建设将这项两年的工作削减到九个月。使用300吨的马尼托沃克4000W环形起重机,在46天内总共放置了496个客房模块。它有一个定制的50吨的容量,82个3米高的倾斜顶部吊杆,以增加可用的负载高度。配备了35吨重的模块,包括家具,使用配有Helicoguide平衡装置的专用负载分散器,在精确到3 / 4英寸(19毫米)的范围内将其吊到位。这包括一个西科斯基直升机发动机和60马力的发动机。

Instead of the planed 10 complete rooms aday, builders ended up lifting in 35 modules a day, illustrating the value ofhaving the right lifting device to achieve full benefit from modularconstruction.

On today’s PPVC projects a twisting moduleis usually put into the right orientation by people pulling on taglines. It isan inefficient approach needing too much manpower and can be dangerous. Insteadof taglines like the Helicoguide of old, an all new suspension device usinggyroscopes can be used. Several products using gyros to control load rotationand eliminate taglines have been launched in the last couple of years. Japanesetower crane manufacturer Kitagawa has one called Gyro-master. The modularEverest series self-contained spreader developed by the Verton Group inAustralia uses a remotely operated variable effort rotator to control suspendedloads up to 1,500 tonnes.




Remote control helps improve safety byremoving riggers from the lifting zone. Cycle time is reduced by as much as 25% and fewer riggers are needed on site.


Kitagawa offers units up to 75 tonnescapacity and there are already units in used in Japan up to 125 tonnes. Thisequipment should be used with a self-balancing lifting frame to minimise timeattaching the load and exact positioning. Such a lifting collar frame can alsooffer multiple slinging points to cope with the module’s structural integrity.It also means no need for a Christmas tree-like arrangement of lifting beamsincreasing the required head height of the crane.


Unfortunately, the original idea to replacesingle modules during the Capsule Tower’s lifetime was not realised


Bolted building

An idea behind Tokyo’s Nakagin CapsuleTower of 1972 was that each of the one-room pods measuring 2.5 x 2.5 x 4 metresand bolted using four high-tension bolts to the lift core, could be replacedany time without disrupting the rest of the building. Modules were intended forreplacement every 25 years which gave the flexible structure a life expectancyof 200 years. Unfortunately, no lifting device was developed to insert thecapsules so only the top capsules can be removed. Replacing a lower onerequires removing all above it.


Moving up to date, the hot spot for PPVCprojects has been Singapore since 2016. It was driven by an ambitiousgovernment roadmap to improve construction industry productivity. Initially thelight weight modules could be handled by 300 tonne-metre class tower cranes.Module weight has increased dramatically in the last three years to reduce costand raise productivity.


It has severely impacted tower crane sizeand design. At first high capacity models were unavailable so cranes designedfor industrial projects had to be adapted. In the last year new models havebeen appearing to address the needs of PPVC.


Singapore is a typical tower crane rentalmarket. Some contractors like to operate high capacity tower cranes in pilotprojects but tower crane rental companies can only realise the amortised costafter a few more PPVC projects, before the savings can be passed on todevelopers.

To improve the availability of large cranesthere must be confidence in the future of concrete modular construction. Atpresent authorities in Singapore prefer the heavy concrete modules forresidential buildings. In other regions concrete structures are viewed lessfavourably in terms of carbon dioxide emission. Lighter hybrid modulesincorporating timber and steel are preferred and the cranes can be smaller.


Each construction site needs its own craneconcept but there are some general rules for a common high-rise residentialtower construction:


) If possible trucks delivering the modulesshould be unloaded close to the building and the tower crane be positioned inthe centre of the site to minimise requested working radius and capability ofcrane. Unlike conventional precast, PPVC modules are usually too big to bestored on site. Just in time transport and installation could be mostefficient.


For reinforced concrete modules, includingload spreader, capacity between 28 and 45 tonnes is needed, to a working radiusof 35 metres, depending on the crane location and building shape. Thattranslates as an 850 to 1,600 tonne-metre capacity class machine. For steelmodular and hybrid units about 15 to 25 tonnes lifting capacity is required toa working radius of 30 or 35 metres. That means 450 to 900 tonne-metre classcranes.


) To reach all the site the capacity needsto be available right out to the end of the crane’s jib.


) Rental periods are shorter with PPVC thanconventional construction. In Singapore conventional construction of a typicalresidential tower is about 16 months. PPVC, typically with 2,000 modules perresidential project, will reduce jobsite duration for the crane to 8 to 12 months.Building a podium or lift shaft, by slip forming concrete, can be done withsmaller cranes, thereby reducing the time needed for the large cranes.Considering the costs for mobilisation and demobilisation, however, it is stillusually more economical to choose one size crane for the entire project.


4.) In Singapore tower cranes are notallowed to oversail neighbouring sites. Short counter jibs and flexible jiblength are therefore required. In some cases, the out of service slew lock hasto be used, which is easier in very short jib conditions.

4)。在新加坡,塔式起重机是不允许在邻近的地点进行海上运输的。因此,需要短的反臂和柔性臂长度。在某些情况下,必须使用停机后摆锁,这在非常短的臂架条件下更容易使用。5.) Minimising environmental impact during construction is becomingmore important, especially on inner city sites. In Singapore working hours inthe construction industry are stringently regulated. No work is permitted from22.00 hours on Saturday until 07.00 on Monday. Noise limitations include a 1hour limit for continuous noise of 65dBA or higher within 15 metres ofresidential zones. Carbon dioxide emission and transport traffic to the sitehave to be reduced as far as technically possible.


6.) Luffers show true value in very tightareas. In most cases, however, a compact hammerhead crane with reduced jiblength and adapted to the site conditions is more cost effective. It is up to40 % less to manufacture and is faster to rig. In addition, these cranesgenerally produce lower reaction forces, have lower power consumption and cansimplify anti-collision management.


7.) Where hammerhead cranes are used, aflat top design is preferred due to, in most cases, faster set up times andlower overall height. A flat top crane is easier to change jib and counterjiblengths because there are no pendants.


8.) Handling modules on a typical PPVCconstruction means using the maximum load moment of the crane for most of itsworking time. Using the full length of the jib means a single trolley ispreferred. In addition, it is preferable to use all the available jib length toplace modules al the way to the maximum available outreach of the crane. Hencewhen using a saddle jib crane a single trolley is preferred instead of a doubletrolley arrangement common on other heavy lift tower crane designs.


9.) Precise lifting is more critical thanspeed. Soft start frequency inverter systems with micro move control are indemand. Also popular are a camera system to follow the hook block and one toshow hoist rope spooling. Using smart GPS sensors on the lifting frame allowstransmission of real time information to the construction software. Datalogging allows interrogation of the entire crane operation via the internet.Nanyang Technological University researchers had such a smart crane at theSignature at Yishun condominium site. Each precast module had its own radiofrequency identification. It could be tracked from leaving the factory to beinghoisted into place. A computer model calculated the ideal lifting path for thecrane for each load. Added together productivity was up by between 10 and 20 %and time savings of up to 30 % were recorded.

10.) Singapore allows a maximum freestanding height of 40 metres. A maximum of 40 metres is allowed above the lasttie back to the building in other regions so high free standing capacity is apopular request to save money on ties. For road transport a maximum componentdimension of 3 x 3 metres is requested.

9)。精确的提升比速度更关键。需要具有微动控制的软启动变频系统。也流行的是一个相机系统跟随挂钩块和一个显示葫芦绳卷轴。在升降架上使用智能GPS传感器,可以将实时信息传输到施工软件。数据记录允许通过互联网对整个起重机操作进行询问。南洋理工大学(Nanyang Technological University)的研究人员在逸顺公寓(Yishun con公寓楼)的签名处就有这样一台智能起重机。每个预制模块都有自己的无线电频率识别。它可以被跟踪,从离开工厂到被吊装到位。用计算机模型计算出了起重机在各载荷下的理想提升路径。加在一起,生产力提高了10%到20%,节省了高达30%的时间。



A new Jaso heavy lift tower crane is on thedrawing board and will very soon close the gap between the J700 and the giantJ1400


On the job

The first 40 storey towers of the ClementCanopy project in Singapore were 18 to 32 tonne concrete PPVC modules. Theywere placed by two standard Liebherr 1000EC-H40 Litronic cranes with 40 tonnescapacity at 27.1 metres radius. Jibs were 34.5 metres with a double trolley.Standard features such as micro-move, EMS electronic monitoring and the 17metre short counter jib qualified this crane for heavy PPVC construction workback in 2017.

新加坡Clement Canopy项目的第一个40层塔楼是18到32吨的PPVC混凝土模块。它们由两台标准利勃海尔1000EC-H40轻型起重机放置,载重量40吨,半径27.1米。三角架为34.5米,采用双滑轮。micromove、EMS电子监控和17米短臂等标准功能使该起重机在2017年就有资格从事重型PPVC施工工作。

At the same time two more 1,000 tonne-metreclass units were available in Singapore. These were Krøll K1000s, with 40tonnes capacity at 26.2 metres radius but using a single trolley. They had acustom built 18 to 24 metre short counter jib instead of the normal 27 metres.

与此同时,新加坡还有另外两艘1000吨级的潜艇可供使用。这些是Krø我K1000s, 40吨容量为26.2米半径,但使用一个电车。他们有一个定制的18到24米短的反臂,而不是正常的27米。

During the next development stage of PPVCconstruction, in 2018 and 2019, crane cost control became as important asraising the load moment to cover a wider working radius as well as making thecranes more compact to serve overlapping construction areas with a number ofcranes. Flat top models here proved their worth.


Rental specialist Tiong Woon Corp. (TWC)ordered 20 units of the Yongmao STT1330 and STT1830. The STT1330 is availablein 64 tonne and 50 tonne versions. It can lift 64 tonnes at a 21 metre radius.Capacity is 34.25 tonnes at the end of the 35 metre jib. The STT1830 lifts 64tonnes to 30.5 m and has a tip load of 46.6 tonnes on a 40 metre radius.

租赁专家Tiong Woon Corp. (TWC)订购了20辆Yongmao STT1330和STT1830。STT1330有64吨和50吨两种型号。它能在21米的半径内举起64吨重的重物。35米长的三角帆末端的载重量为34.25吨。STT1830起重机载重64吨至30.5米,在40米的半径内载重46.6吨。

According to site conditions the counterjib can be reduced to 15.2 metres for jib lengths up to 40 metres. Latest ofthe big Yongmao models is the all-new STT983-50t with a 15.2 metre counterradius, 50 tonne capacity (4 falls) and 22.97 tonne tip load at 45 metreradius. More than 20 units are scheduled for delivery to Singapore in 2020.



More for TWC

In 2019 ten more heavy lift flat tops wereordered by TWC, this time the T1200-64W from Zoomlion. The 17.1 m counter jibversion allows the 64 tonne capacity crane a tip load of 37.18 tonnes at 35metres radius.


Comansa has a long record of success inmodular construction with its 2100 series. Since 2018 the 50 tonne capacity21LC1050 comes with six modular counter jib lengths up to 20 metres for 35metre jib radius. At 30 metres outreach the capacity is 43.67 tonnes. In 2019the 21LC1400 was added, with PPVC construction in mind. It has a modularcounter jib so at 18.6 metres long, with 34.4 metre jib, the tip load is 48.4tonnes.


Jaso has sent four of its 64 tonne J1400giants to Singapore. Designed in 2019 this crane offers four modular counterjibs, with an 18.1 metre minimum radius. Capacity is 36 tonnes at 40 metresradius. Despite its size the complete crane can be shipped in standard highcube 40 foot containers.


At the time of writing a smaller version ofthe Jaso, between the J1400 and J700, was under development. It will also offerfour counter jib lengths to accommodate PPVC site restrictions.


Another new entrant to the Singapore marketwill be the flat top Krøll K860F, a reinforced version of the K830F. It retainsthe larger model’s design optimised for transport and rigging. Capacity is 48tonnes at 19.6 metres radius and 24.8 tonnes can be lifted at 34.9 metresradius with the newly-designed compact single trolley. On their first job sitefour cranes will be rigged with just 20 metre and 34.9 metre jibs and counterjibs of 16.1 metres.

另一个新进入新加坡市场将成为平顶Krø我K860F, K830F的增强版本。它保留了更大的model s设计,优化了运输和索具。新设计的紧密型单轨电车以19.6米为半径,载重量为48公吨;以34.9米为半径,载重量为24.8公吨。在他们的第一个工地上,四台起重机将安装20米、34.9米和16.1米的反臂。

Wilbert TowerCranes sees a market forPPVC projects coming up in Europe. Capacity of the all new WT1000 e.tronicis 48 tonnes at a 22 metre radius and 26.5 tonnes can be handled at 40 metres.

Wilbert TowerCranes认为PPVC项目在欧洲有一个市场。全新的WT1000 e.tronic在22米半径处的处理量为48吨,在40米半径处的处理量为26.5吨。

Specially designed hydraulic spreader beamfor the Habitat 67 project

为Habitat 67项目特别设计的液压吊具梁

Smaller space

At even more cramped sites in Singapore,luffers like the new Yongmao STL1400A, with 50 tonnes capacity at 27 metres, or34 tonnes at 36 metres, are in use. Electrically driven Favelle Favco and Krøllluffers are also sound alternatives for heavy modular construction. On thedrawing board in Japan is a Kitagawa luffing jib tower climbing craneespecially suitable for heavy PPVC projects. It will boast a compact 8 metretail radius, 64 tonne capacity out to 36 metres radius and 30 tonnes to 51metres in 4 fall operation. It will sit on a 64 metre free-standing and compact2.5 x 2.5 metre tower system.

在新加坡更拥挤的地方,像新永茂STL1400A这样的luffers正在使用中,27米的容量为50吨,36米的容量为34吨。电动Favelle Favco和Krø我变幅机构也声音替代重型模块化建筑。日本图纸上有一种特别适合于重型PPVC项目的北川变幅臂塔攀爬起重机。它将拥有一个紧凑的8米尾部半径,64吨的容量到36米的半径和30吨到51米的4次降落操作。它将坐落在一个64米的独立而紧凑的2.5×2.5米的塔系统上。

In Europe, the UK’s construction industryhas shown the most advanced way to raise residential towers following PPVCprinciples. It is demonstrated in London on 101 George Street’s 135 metre-high,44-storey building of 546 apartments. It comprises 1,524 hybrid steel moduleswith concrete bases lifted into place using two Terex CTL650F45 luffers. Thesecranes offer a 42 tonne capacity on three falls mounted on top of the twincores completed in advance using slipform construction.

在欧洲,英国的建筑业已经展示了最先进的方法来建造遵循PPVC原则的住宅楼。它在伦敦乔治街101号一座135米高、44层、有546个公寓的建筑上得到了展示。它由1524个混合钢模块和混凝土基座组成,使用两个特雷克斯CTL650F45 luffers吊装就位。这些起重机提供了42吨的能力,安装在双芯顶部的三个瀑布使用滑模结构提前完成。

On this job a one-bedroom apartment isbuilt from two modules, one for the living room and kitchen and the other forthe bed and bathroom. The 23 differently configured modules are 95 % finishedwhen they arrive on site. Delivery and installation is at a rate of 10 to 12modules per day in a 32-week programme. Mast climbers are used to fit thecladding which frees up the cranes for installing the modules. The project isscheduled for completion in May 2020.



Lighter loads

More environmentally considered modularconstruction materials are being tested. A 14-storey timber-framed luxuryapartment block in Bergen, Norway, was erected using a Potain MD365. It placedthe 14 tonne timber modules and the 12 tonne pieces of laminated timberframework bracing the building structure. Completion was in 2015 and nowanother spectacular 18 storey wooden apartment building is on the drawing board.Toronto Tree Tower is inspired by the Montreal habitat 67 building. This time,however, its prefabricated modules of cross-laminated timber are designed to beput together in a similar way to the bricks of a Lego toy construction set.

Most PPVC projects show a 50 % reduction inconstruction time at the building site when compared with traditionalconstruction but they end up being just 10 % cheaper. It is not only due to thelarge lifting equipment required. More than this it indicates a need to raiseproductivity simply by doing more PPVC projects and making modular constructionmainstream.

目前正在测试更环保的模块化建筑材料。在挪威卑尔根,一座14层的豪华木结构公寓大楼是用Potain MD365建造的。它放置了14吨的木材模块和12吨的木结构支撑建筑结构。该项目于2015年完工,现在,另一座壮观的18层木制公寓楼正在设计中。多伦多树塔的设计灵感来自蒙特利尔人居67大楼。然而这次,交错木材的预制模块被设计成以类似的方式放在一起乐高的积木玩具建设集。大多数PPVC项目显示在建筑工地施工时间减少50%相比,传统的建筑但他们最终只是便宜10%。这不仅是因为需要大型起重设备。更重要的是,它表明需要通过做更多的PPVC项目和使模块化建设成为主流来提高生产力。

Modular tower crane design has allowed eventhe requirements of Singapore’s demanding market be quickly addressed by mostmajor crane manufacturers. For 2021 a slower supply of new large tower cranesfor PPVC construction can be expected in comparison to the boom years of 2018and 2019. In other core markets, however, labour shortages and large-scaleunmet demand for housing will intersect and make the idea of modularconstruction particularly relevant. Experience collected in Singapore and byother PPVC pilot projects around the world can help keep costs for efficientand, at the same time environmentally conscious lifting equipment, under control.


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