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（1 中國核電工程有限公司， 北京 100840； 2 北京交通大學(xué)， 北京 100044）

［摘要］預(yù)應(yīng)力積成材是將膠合板材剖解成片狀單元，然后將片材垂直于板面排列，再由預(yù)應(yīng)力鋼絲將其貫穿、擠壓形成整體的一種新型結(jié)構(gòu)材料。本文應(yīng)用有限元軟件對(duì)其力學(xué)性能進(jìn)行了分析研究。從簡支單板面內(nèi)受彎的承載力分析切入，通過改變構(gòu)件的幾何參數(shù)得出了單板內(nèi)力分布、破壞模式以及承載力的變化規(guī)律，然后分析了預(yù)應(yīng)力積成材的內(nèi)力分布和破壞模式，并且通過對(duì)預(yù)應(yīng)力大小、預(yù)應(yīng)力鋼絲的直徑及其縱向間距、預(yù)應(yīng)力鋼絲的上下邊距等參數(shù)的分析確定了極限承載力隨影響因素的變化規(guī)律。分析結(jié)果表明：單板構(gòu)件的高寬比越大，破壞模式越趨向于失穩(wěn)破壞，材料強(qiáng)度越不能得以充分發(fā)揮；通過預(yù)應(yīng)力鋼絲的合理選取與布置及預(yù)應(yīng)力的合理施加，分散的單板結(jié)合成一個(gè)共同受力和變形的整體，使預(yù)應(yīng)力積成材的承載力遠(yuǎn)高于失穩(wěn)破壞時(shí)的極限承載力且稍高于等體積原木的承載力。最后提出了合理參數(shù)下積成材的分析模型。

［關(guān)鍵詞］預(yù)應(yīng)力積成材； 非線性屈曲分析； 極限承載力； 參數(shù)化分析

中圖分類號(hào)： TU398.6 文獻(xiàn)標(biāo)識(shí)碼： A文章編號(hào)：  1002-848X(2016)S1-1038-08

Numerical study on mechanical properties of pre-stressed paminated strand lumber

Ma Jia1, Yang Qingshan2

(1 China Nuclear Power Engineering Co., Ltd., Beijing 100840, China; 

2 Beijing Jiaotong University, Beijing 100044, China)

Abstract： Pre-stressed laminated strand lumber(PLSL) is a new kind of structural material which can be gotten by connecting and squeezing the vertically arranged sheet units sawing from plywood by pre-stressed steel wires. The load-carrying capacity of the simply supported plate under inside compression is analyzed to discuss the varying rules of the internal forces distribution, failure mode and ultimate bearing load with the height-width ratio. In addition, the distribution of internal forces and the failure mode of PLSL are discussed. Then the influences of magnitude of pre-stress, distribution of steel wires, diameter of steel wires, longitudinal spacing of steel wires, as well as edge distance of steel wires on ultimate bearing load are discussed by parametric research. The analysis results show that, the larger of the height-width ratio, the greater tendency of the instable failure, and more percentage of the material strength can not be exploited; Dispersed veneers can be deformed as a whole through reasonable selection and distribution of pre-stressed steel wires. So the ultimate bearing load of PLSL is much higher than the instability bearing load, and slightly higher than the crude wood of same volume. At last, an analysis model under reasonable parameter is put forward.

Keywords： pre-stressed laminated strand lumber; nonlinear buckling analysis; ultimate bearing load; parametric research